[Spokerider]

Hello gents,

I have a few questions about my 87 samurai please, and am hoping from input from those with experience about spoa and spua zuk suspension differences.

Currently, I'm spoa, yj's front and rear with custom 2" lift springs for the front. Stock zuk axles, Sky OTT steering [ just the knuckles ] custom drag link and original zuk tie rod. Steering box in an FJ80.....this is mounted on the outside of the frame rail, the pitman arm points forward.
I also have a vw 1.9TD engine swap........so the oil pan on the diesel hangs lower than the oem zuk 1.3 oil pan did. This is one of the main reasons that I went spoa to begin with......to provide clearance between the vw oil pan and the zuk diff / axle housing, with suspension compression. Without "some" added clearance here, from one mod or another, hitting is inevitable with a totally stock zuk suspension.

Ok....more.....

I do not like the tall ride height of my spoa zuk. It is for mild trail / hunting use on our logging roads, and also a DD. I need it to feel more stable on the pavement than it does now, especially for cornering above 60kmh on sweeping paved roads.
All of the components used on my build are either new or rebuilt....axles, knuckles, seals, bearings....all new. Spring bushings all new. Nothing is worn, loose or damaged. The caster angle is 7 deg positive, as it sits.

I'm wanting to go spua with these components mentioned. I have more yj spring leafs to fine tune the spring packs if necessary.

Now for the questions......
Will going from spoa with these parts, to spua make an *appreciable* improvement difference in the handling / steering? Or, just a little bit of difference that is hardly worth the effort of the swap?

How much suspension "up travel" is normally achieved with yj spua?
What is the limiting component/s as far as getting maximum up travel? What will hit what? As mentioned.....I need the clearance for the diesel oil pan.

Here is a pic of my build. It is the most current pic, but I no longer have the 33's on. It has 31's now. I no longer have the panhard bar attached [ it was hitting with only 1.5" up travel ].

Thanks for you experienced input!

[Gwagensteve]

I was going to reply in the pirate thread.

I’ll reply in detail when I’m in front of a computer. In short, it’s hard to imagine a worse setup for road driving than what you have now, apart from the panhard rod.

[Spokerider]

Ok thank you.
Looking forward to your knowledgeable input.
Yes, I see you on Pirate too.

[Spokerider]

On a similar note.......
I emailed Brent at Trail Tough regarding amount of "up travel" on a Samurai and his Epic SPUA kit. He said to expect 3.5" with the zuk 1.3 engine.

Ok, that's more than I have now....... could similar up travel be had with my yj's up front, instead of the Bonz Eye springs that come in the Epic kit?
I only have 2" right now, and could do with more if it can be obtained [ with the vw diesel ].

[alien]

Mine's SPOA and passed the lane change (moose) test, so you can keep it SPOA and have it handle on the road. My perches are quite tight to the diff housing providing very little added lift, and I only run 3 leaves in my spring packs, resulting in near flat leaves. I do however have trac bars (caltracs style) in the rear due to excessive wrap.

[Gwagensteve]

Yes, but your car is substantially lower and better conceived. Additionally, a lane change test is a pretty one dimensional assessment of handling.

[Gwagensteve]

OK. Sitting in front of a computer.

As you're aware, this is an Australian based site. This means there are some significant differences in what we do here compared to the US market. Having said that, I'll say I believe we are well ahead of the US market in the way we build our cars, because mostly, we're aiming to improve on what makes them better than larger cars rather than turn them into a larger car.

SPOA hasn't been popular here for almost 20 years now. They have always been difficult and expensive to make road legal, but that's not the biggest issue, the problems have always been the compromised off road behaviour, mostly unreliability and instability, that saw the SPOA cars being outdriven by SPUA cars. There's nothing worse than turning up to a trail trip in a fresh completed SPOA car and being outdriven by basic SPUA cars because you can't take their lines.

Anyway, on to the specifics of our market.

First of all, we never had the YJ Wrangler sold here new. As a result, bracket kits to run those leaves are pretty much non-existent here. This isn't important - springs and springs are springs, but the specifics of rate and leaf combination won't be something I/we can help with very much.

The VW TDI conversion is pretty much non-existent here too. Despite everyone on Facebook thinking they're going to do one. This is because the only version of the 1.9 TDi we received here was computer controlled/common rail, and therefore expensive and complex, but also the turbo will foul the steering in our RHD market. Again, no big deal, I understand the TDi requires about 3" of bumpstop spacing.

Only you can decide if that makes my/our advice useful or not, but I tend to think the elements of sound vehicle construction and handling are the same wherever we are in the world- the specifics are pretty unimportant.

I need to understand what it is specifically that you're unhappy with. I'm sure the car is unstable, but I'm sure you haven't actually had it fall over, so the actual limit of stability might be a fair bit higher than you're experiencing in your driving, so I’m interested in what that instability feels like. Is the problem body roll/pitching/bump steer/roll steer etc? Try and be as specific as you can.

Can you clarify the front shackle hanger situation? Is that a "missing link" or "folding/double shackle" setup? It looks to be one from what I can see here and on Pirate. I'll assume it is for now.

Why are you only able to achieve 2" of uptravel? what is touching what?

Does the car have functional bumsptops?

What shocks are you running? They look like Bilsteins, if so, what valving is in them?

What tyres and rims (width and BS) are currently on it?

Have you confirmed toe and camber?

I'm going to come out and say this now, I don't think all that many of the existing parts are going to survive the troubleshooting process.

Good points:

If the shocks are soft valved, they can likely stay.
The springs might be able to stay.
At least everything looks to be clean and well serviced.
The 7˚ of caster is good.
Those front shackles look good.

Bad points:

I can’t see how the 80 series steering box can stay. The pitman arm looks like it drops much too far to work with SPUA as evidenced by how far the panhard arm has to be dropped. It will be in the way of the springs if you ever achieve decent compression travel, so lets remove that, along with the panhard mounting brackets.

The axle truss is going to be in the way of the sump even in a 1.3 engined car and isn’t helping anything anyway. These housings typically bend from the spring to the knuckle, not in the middle, and only if jumped in sand. Cut it off and throw it away.

The high steer won’t clear the chassis SPUA, so that needs to go in the bin.

The missing link shackles (if that’s what I’m seeing) are just introducing more unwanted lateral movement and aren’t making the car better at anything except posing on ramps. Throw them away too.

How much droop is in those front springs? If you pin the missing links and jack the chassis up, how much droop do you get before the springs unload? 2” lifted YJ springs on a YJ would have 5” or so of compression, at a guess. If you only have 2” you’re leaving a tonne of spring travel on the table. This is a problem with SPOA – you have to run stiffer springs flatter ( like the Bonz-eye) to locate the axle properly because of the added leverage of SPOA on the leaves. Dropping to SPUA will lower the spring rate you can run but will require more free camber in the springs. This might mean these springs are unsuited to SPUA application and something silly like a 4” lifted YJ spring heavily derated to maybe 2 leaves might be optimal.

The big problem though is that 3” of bumpstop spacing. A worn, stock Samurai only has around 1-1.5” of compression travel to the bumpstop. 2” is the maximum spring lift a Samurai can run due to the short front spring. You’re going to need to have 5” of total spring lift or so to allow 2” of compression travel with 2” bumpstop spacing. That’s too much lift and will never create a stable, comfortable daily, and it’s why ACME recommend SPOA to “fit 31” tires” **sigh** and clear the pan.

2” bumpstop spacing and about 3” of total spring lift is as much as I would contemplate. That would allow 2-2.5” of compression (plenty, honestly) but you’ll need to get an inch of clearance out of the sump, by either cutting the sump, clearancing the axle housing (don’t knock it, I’m doing it now) lifting the motor, or some combination of those things. Don’t rule out a 1” body lift to allow room to raise the engine if the engine/hood clearance is the problem. Samurai’s take a body lift well and the effect on centre of gravity is much lower than suspension lift. A 1” body lift and 2” bumpstop spacing will easily clear 31’s with some very minor guard hammering/seam rolling and with some more guard work 33’s would be just fine.

You’ll need to replace the steering box with something more suitable, inside the chassis, to allow tyre room and spring clearance. A Tracker/Sidekick box will work, but has a fairly flat pitman arm and with 3” of spring lift drag link angle will be a bit unfavourable for bump steer. You can source a JB series Jimny pitman arm will fit a Tracker/Sidekick steering box but has some drop which will help. You’ll then be able to run a stock Samurai draglink.

Yes, this is a massive rework of your existing setup and that’s painful, but I think you’ll end up with a much, much better outcome, on and off road. The car will be much more trustworthy.

PS don’t believe anyone that ever says on road and off road handling are mutually exclusive. Cars that handle badly on road handle badly off road too. If you’re really only doing mild trails and fire roads you’ve really created a very compromised car for no reason.

Steve.

[Gwagensteve]

PS - low is the new lift :middle fangers:

[Spokerider]

Gwagensteve wrote:

OK. Sitting in front of a computer.
Thank you Steve. That is much info to take in
I'll try to answer your questions with a short reply. I can always expand more on the topics later on.

As you're aware, this is an Australian based site. This means there are some significant differences in what we do here compared to the US market. Having said that, I'll say I believe we are well ahead of the US market in the way we build our cars, because mostly, we're aiming to improve on what makes them better than larger cars rather than turn them into a larger car.
Yep, why I'm here!

SPOA hasn't been popular here for almost 20 years now. They have always been difficult and expensive to make road legal, but that's not the biggest issue, the problems have always been the compromised off road behaviour, mostly unreliability and instability, that saw the SPOA cars being outdriven by SPUA cars. There's nothing worse than turning up to a trail trip in a fresh completed SPOA car and being outdriven by basic SPUA cars because you can't take their lines.

Anyway, on to the specifics of our market.

First of all, we never had the YJ Wrangler sold here new. As a result, bracket kits to run those leaves are pretty much non-existent here. This isn't important - springs and springs are springs, but the specifics of rate and leaf combination won't be something I/we can help with very much.
I have lots of yj leafs to play with, and tried 5 different leaf combos in the front before going with what I have.....2" lift springs.

The VW TDI conversion is pretty much non-existent here too. Despite everyone on Facebook thinking they're going to do one. This is because the only version of the 1.9 TDi we received here was computer controlled/common rail, and therefore expensive and complex, but also the turbo will foul the steering in our RHD market. Again, no big deal, I understand the TDi requires about 3" of bumpstop spacing.
The 1.9TD engine and a TDI are different engines. The TDI is taller than the TD. Not sure if the oil pan depth are the same or not. In any case, the diesel oil pan does take up suspension compression space. An oil pan mod is pretty much needed to gain back some of that clearance.

Only you can decide if that makes my/our advice useful or not, but I tend to think the elements of sound vehicle construction and handling are the same wherever we are in the world- the specifics are pretty unimportant.

I need to understand what it is specifically that you're unhappy with. I'm sure the car is unstable, but I'm sure you haven't actually had it fall over, so the actual limit of stability might be a fair bit higher than you're experiencing in your driving, so I’m interested in what that instability feels like. Is the problem body roll/pitching/bump steer/roll steer etc? Try and be as specific as you can.
I'll begin by saying that this is the only samurai I've driven. I bought it 10 years ago, and drove it the 45 minutes to my home. That was the 1st and last time I ever drove it in stock form. My frame off build took 10 years to complete. Here I am now, with only 200km on this build and I'm considering these mods! Honestly, when I began this build, I was going to wheel it on challenging trails......10 years later and many many hours of build time, and my plans have changed to a more sedate use as mentioned. Always planned to use as a DD and still do. So I have very little seat time in any zuk, stockor otherwise to "compare" it with.
So what don't I like........first off it's the height. My wife can hardly clamber up inside now. It feels somewhat "darty" on the road, and all though it tracks well, drives straight, there is a subtle twitchyness about the handling, as if it is threatening to do something nasty, but never crosses the threshold of doing so. Yes, there is body lean in the corners, but those 2" lift springs are actually pretty stiff that is helping limit body lean. The handling feels rather "quick". Is this a product of the short wheel base and 31" tires?? I dunno. Maybe. It prolly does have some bump steer, but the wheel does not get jerked in my hands if I hit a bump. The PS and the ome steering damper are prolly absorbing some of that. The most unsettling handling characteristic seems to be in corners, where if "feels" like it just a little more sketchy than driving straight. Not sure why....maybe the height, body lean, short wheelbase, etc....

Can you clarify the front shackle hanger situation? Is that a "missing link" or "folding/double shackle" setup? It looks to be one from what I can see here and on Pirate. I'll assume it is for now.
Trail Tough Missing Links in front, Trail Tough Bone Shackles in rear.

Why are you only able to achieve 2" of uptravel? what is touching what?
The pitman arm / drag link joint hits the top of the leaf spring on suspension compression. Not hard, but at about 2" it' touches. I'll post up a pic showing the orientation of the components.

Does the car have functional bumsptops?
Yes

What shocks are you running? They look like Bilsteins, if so, what valving is in them?
Bilstien 5125. Not sure the valving, but supposed to be a good shock.

What tyres and rims (width and BS) are currently on it?
15 x 8 with 2.5" back set. Procomp steel wheels. I need the back set clearance for the 2001 Tracker front disc brake swap I did.

Have you confirmed toe and camber?
Yes, camber is 7 deg. I made sure of the accurate measurement. Toe in is .125", confirmed multiple times.

I'm going to come out and say this now, I don't think all that many of the existing parts are going to survive the troubleshooting process.

Good points:

If the shocks are soft valved, they can likely stay.
The springs might be able to stay.
At least everything looks to be clean and well serviced.
The 7˚ of caster is good.
Those front shackles look good.

Bad points:

I can’t see how the 80 series steering box can stay. The pitman arm looks like it drops much too far to work with SPUA as evidenced by how far the panhard arm has to be dropped. It will be in the way of the springs if you ever achieve decent compression travel, so lets remove that, along with the panhard mounting brackets. I have another flatter, shorter pitman arm that I would like to try before tossing the FJ 80 box. It is from an 80's 2WD toy truck and will fit the FJ box shaft. My whole diesel build is built around the FJ80 box, choice or rad, placement of rad, etc. I would like to keep PS. The Tracker box could be an option, I'd need to look into it to see how it fits with the 1.9TD and with power steering pump on the left side of the engine. Yep, I could remove the panhard bar mount.

The axle truss is going to be in the way of the sump even in a 1.3 engined car and isn’t helping anything anyway. These housings typically bend from the spring to the knuckle, not in the middle, and only if jumped in sand. Cut it off and throw it away.
Yep, it can get tossed.
The high steer won’t clear the chassis SPUA, so that needs to go in the bin.
You're saying remove the Sky steering arms?? or just the tie rod portion of the OTT steering? I'm not using the OTT tie rod now, just the steering arms and my custom drag link.

The missing link shackles (if that’s what I’m seeing) are just introducing more unwanted lateral movement and aren’t making the car better at anything except posing on ramps. Throw them away too.
The purpose they serve is mount the yj springs [ longer than zuk springs ] to the frame. I can lock them out so they don't open / drop down. Toss them and replace them with what?

How much droop is in those front springs? If you pin the missing links and jack the chassis up, how much droop do you get before the springs unload? 2” lifted YJ springs on a YJ would have 5” or so of compression, at a guess. If you only have 2” you’re leaving a tonne of spring travel on the table. This is a problem with SPOA – you have to run stiffer springs flatter ( like the Bonz-eye) to locate the axle properly because of the added leverage of SPOA on the leaves. Dropping to SPUA will lower the spring rate you can run but will require more free camber in the springs. This might mean these springs are unsuited to SPUA application and something silly like a 4” lifted YJ spring heavily derated to maybe 2 leaves might be optimal.
Not totally sure what you're asking here...... As far as jacking the frame up and letting the springs drop [ with the weight of the wheel ] , and then jacking up further until the ML shackles open up, I'm not sure and have not taken those measurements.

The big problem though is that 3” of bumpstop spacing. A worn, stock Samurai only has around 1-1.5” of compression travel to the bumpstop. 2” is the maximum spring lift a Samurai can run due to the short front spring. You’re going to need to have 5” of total spring lift or so to allow 2” of compression travel with 2” bumpstop spacing. That’s too much lift and will never create a stable, comfortable daily, and it’s why ACME recommend SPOA to “fit 31” tires” **sigh** and clear the pan.
IF I had the zuk 1.3.....what would the ideal spring lift be for yj spua? How much suspension compression would this "ideal lift" get me? Yes, the 1.9TD pan will subtract from this compression figure, I realize this, but just not sure by how much yet

2” bumpstop spacing and about 3” of total spring lift is as much as I would contemplate. That would allow 2-2.5” of compression (plenty, honestly) but you’ll need to get an inch of clearance out of the sump, by either cutting the sump, clearancing the axle housing (don’t knock it, I’m doing it now) lifting the motor, or some combination of those things. Don’t rule out a 1” body lift to allow room to raise the engine if the engine/hood clearance is the problem. Samurai’s take a body lift well and the effect on centre of gravity is much lower than suspension lift. A 1” body lift and 2” bumpstop spacing will easily clear 31’s with some very minor guard hammering/seam rolling and with some more guard work 33’s would be just fine.
I could do a 1" body lift as an option.
When you say 3" spring lift, what does that mean? That the yj springs are 3" more arc height than oem flat 4 pack, yj springs?

You’ll need to replace the steering box with something more suitable, inside the chassis, to allow tyre room and spring clearance. A Tracker/Sidekick box will work, but has a fairly flat pitman arm and with 3” of spring lift drag link angle will be a bit unfavourable for bump steer. You can source a JB series Jimny pitman arm will fit a Tracker/Sidekick steering box but has some drop which will help. You’ll then be able to run a stock Samurai draglink.
If I had a Tracker PS box, 3" "spring lift", and oem zuk drag link and tie rod, would there be any clearance / fitment issues with the 2-2.5" suspension compression? I've never seen this combo before , so can't visualize it.

Yes, this is a massive rework of your existing setup and that’s painful, but I think you’ll end up with a much, much better outcome, on and off road. The car will be much more trustworthy.
About the only this I'm not willing to do is toss the 1.9TD [ to go back to the 1.3 ] and Acme rad, toss the zuk axles or do more welding frame mods. Swapping PS box, tie rod, springs, etc is all doable.

PS don’t believe anyone that ever says on road and off road handling are mutually exclusive. Cars that handle badly on road handle badly off road too. If you’re really only doing mild trails and fire roads you’ve really created a very compromised car for no reason.
Yeah, like I've mentioned, this zuk needs to be able to drive on the hwy, for hours, safely, so my wife and I can get to the areas that we wish to explore off pavement. Foresty roads, overgrown forestry roads, dry creek crossings, cross ditches, occasional mud holes, ice, snow, over fallen trees or paths around them, etc... Just no rock crawling, mudding, and near- roll over trails.
Steve.

I'll post up pics of my build in the various stages of trying out different components. So, the top pic is the most current one as mentioned.

[alien]

Have you considered selling this one and buying a less molested one? =)

[Gwagensteve]

I still can’t work out why it’s bumpstop spaced down so heavily. Obviously the pitman arm will foul the spring, but surely it’s not bumpstop spaced to prevent that?

Looking at all that work, I’m kind of with Alien. That’s a lot to undo.

[vet 180]

Gwagensteve wrote:

I still can’t work out why it’s bumpstop spaced down so heavily. Obviously the pitman arm will foul the spring, but surely it’s not bumpstop spaced to prevent that?

Looking at all that work, I’m kind of with Alien. That’s a lot to undo.

It does look like it tbh. I must say I feel for the guy, spent 10 years and many monies building the car, finally gets to drive it, doesn’t like it then jumps on here and gets told to throw it in the bin and start again [emoji51]

To the OP there is a lot of sound advice on this forum, so you should get steered in the right direction.

The YJ aftermarket isn’t as strong in aus no one goes that route so people will not know the specifics asked in your questions, instead rear springs up front is the preferred choice for longer springs. YJ’s are a bit longer again. Gwagon would be referring to total lift from stock, not YJ spring lift, tbh that seems like the easiest part to get set up especially considering you have many packs to play with. Your current set up must be getting a lot of spring wrap?



Sent from my iPhone using Tapatalk

[Spokerider]

alien wrote:

Have you considered selling this one and buying a less molested one? =)

No way! Not going to happen.
It's totally rust free now. I'd never get another one from my parts this clean, without buying from the dessert in the USA somewhere......

[Spokerider]

vet 180 wrote:

Gwagensteve wrote:

I still can’t work out why it’s bumpstop spaced down so heavily. Obviously the pitman arm will foul the spring, but surely it’s not bumpstop spaced to prevent that?

Looking at all that work, I’m kind of with Alien. That’s a lot to undo.

It does look like it tbh. I must say I feel for the guy, spent 10 years and many monies building the car, finally gets to drive it, doesn’t like it then jumps on here and gets told to throw it in the bin and start again [emoji51]

To the OP there is a lot of sound advice on this forum, so you should get steered in the right direction.

The YJ aftermarket isn’t as strong in aus no one goes that route so people will not know the specifics asked in your questions, instead rear springs up front is the preferred choice for longer springs. YJ’s are a bit longer again. Gwagon would be referring to total lift from stock, not YJ spring lift, tbh that seems like the easiest part to get set up especially considering you have many packs to play with. Your current set up must be getting a lot of spring wrap?



Sent from my iPhone using Tapatalk

Thanks for the reply. It's all useful, thank you.

Ok....so for "spring height"....... you're referring to height over stock zuk springs....I get it now.
Yes, you fellas build your zuks differently from "most" in North America, which is why I'm here, to get opinions based upon your build designs and the feedback you have from driving them.
Seems most guys in my parts will do a spoa lift, the absolute cheapest and easiest way possible.......and not surprisingly, it goes from being a decent road zuk to trailer rig only, in one felled swoop. No in-between, decent road handling manners left. Thus, feedback from these guys is mostly based upon their $100 ghetto lift efforts and amount of spring flex...... Now, I'm not faulting them, it works for their rides and needs.....just saying that it isn't helpful to me.

Yes, I realize that you guys don't have much access to yj springs, and use other springs to get your mods done. We have lots of yj junk to source here, but have ZERO availability for Jimney parts, like a Jimney pitman arm. I guess if I want that, I'll need to get it from ebay.
I'll stick with the yj's for the front and rear, and play with the leafs as needed.

So......thots on optimum spring compression with spua [ with whatever springs are chosen ] with keeping on track with good handling and steering characteristics for pavement. 2-2.5" ?? And what ever the "spring drop" is, again, given the choice of springs used, is what it is, be it 4" or 5" or?? Have i got this correct?

Also, what is the optimum caster angle that you seek for a spua with powersteering and 31's? I did have shims under my spring packs, and it brought the caster to 3.5 deg. I found the steering to be too quick, and was slower to return to center after a turn, so I removed the spring shims. At 7 degrees caster now.

Anybody have pics of a spua zuk with Tracker power steering? Or, spua pics showing different tie rod, pitman and box options? Any pics of best forward / rearward placement location of the zuk axle, for no interference of components with suspension compression?

Thanks for your thots.

[Spokerider]

[bumstein]

Woah!!! There is some serious love gone into that beast!!! Not my kind of build but I can really appreciate the time, effort and cash gone into it. Great work!!!

[alien]

Spokerider - what about retaining the SPOA but lowering it?

Check my build thread:
viewtopic.php?f=4&t=22354&hilit=the+ufo

Mine uses Toyota Hilux front leaves - they're very similar to YJ, except they're wider.

[Gwagensteve]

OK, sorry, I missed your comments on my post on the phone this morning.

There's a massive bag full of compromises you've built in here and they're all conspiring against you.

The "dartiness" you're feeling is likely to be due to the height causing dramatic weight transfer. The rim offset and those terrible tyres are contributing quite a bit too (not the size - 31's are just fine) . I'm sure the springs are quite stiff, and that won't be helping. It's also important to understand the shock valving you have. The stiff valving will be terrible with the stiff spring rate, if that's what you have. (few people chase up the soft valving, which gives a lovely plush ride)

out of interest, why have you removed the panhard? lots of people are trying to work out how to fit them, even SPUA.

Incredibly, that pitman arm is largely responsible for all the problems you're facing. It's obviously limiting compression travel and there's no way you can lower the car and maintain acceptable compression travel with it in place. A flatter pitman arm will be a must if you retain the 80 series steering box, but I genuinely don't think you can with sensible rim backspacing and a low car.


As for the 2.5" backspacing, Thats not helping anything. A 0 to -13 offset (~3.75-4" backspace) is ideal and will help handling and allow the car to be lower because club radius is reduced. Obviously the reduced leverage on the front axle will be very helpful with the heavy Diesel. The 2001 rotors are too big and have inadequate offset to clear the well of 15" rims. You need 4 door Tracker brakes from a 1.6 MPFI car. These will clear any rim backspacing and the pads are basically the same size, however, ~4" backspacing will require you to move the shock hoops - the tire will contact the shock hoop at full lock/full flex.

I can see the clearance issues for an inside-the-rail steering box, but I can see interference between the spring and the sector shaft being an issue at full compression. an IFS pickup box will run outside the rail but has a rear facing pitman arm. Something to consider.

As for the drag link, yes, you won't be able to retain the sky steering arm at all, it will put the drag link too high and it will foul the chassis once the car has been lowered. I can see at some point you've swapped the the rod back to the standard location and off of the sky arms. Good move - the Ackerman angle looks to be way out on the sky arms.

Personally, I'd run toe at 0 with bias ply tires. toe promotes sketchy steering, but .125" should be OK.

OK, the missing links aren't helping anything. They're introducing more lateral movement in the axle. Replace them with proper, welded on shackle hangers.

In relation to jacking the chassis up and observing how much droop is in the springs, The idea is to determine how deep into the spring's travel you're running. I reckon you're not compressing them all that much at ride height. That's bad for ride quality and handling.

Any time I mention spring lift, I'm referring to compared to a factory standard Samurai.

There's no ideal spring lift for a particular spring, that's back to front. THere's and ideal height for the vehicle, which is as low as you can feasibly run. The task then is to build the car and choose springs that enable that. I'm suggesting that if you require 2" bumpstop spacing over standard to clear the sump, and you need to maintain about 2" of compression travel to maintain adequate on-road handling, you need about 2.5" of spring lift compared to a factory Samurai. you can de-camber or de-rate your YJ springs to achieve this, which will be a balance of maintaining adequate spring rate to support the diesel and prevent significant axle wrap and brake dive, but have a low enough rate to promote a good ride and get the car to settle deep into the springs travel.

A tracker steering box, 3" of spring lift and tracker PS box is a pretty common setup and everything clears well. However, as you point out, you're running the front axle a fair way forward. anything over 1.5" forward will create clearance problems between the pitman arm and the tie rod at full compression. I don't think a tracker box is feasible for you because of your radiator and engine, so lets stay away from that for now and rely on your 80 series box with a flat(ter) pitman arm.

How far you can pull the axle forward will depend on how far you're willing to get into the headlight buckets - with good flex and compression travel, a 31 will require some work around the front of the guard to clear.

That'll do for now.

Steve.

[Spokerider]

Gwagensteve wrote:

OK, sorry, I missed your comments on my post on the phone this morning.

Thank you for taking the time to reply Steve, I appreciate it.

There's a massive bag full of compromises you've built in here and they're all conspiring against you.

The "dartiness" you're feeling is likely to be due to the height causing dramatic weight transfer. The rim offset and those terrible tyres are contributing quite a bit too (not the size - 31's are just fine) . I'm sure the springs are quite stiff, and that won't be helping. It's also important to understand the shock valving you have. The stiff valving will be terrible with the stiff spring rate, if that's what you have. (few people chase up the soft valving, which gives a lovely plush ride)
I no longer have those Interco bias 33" tires on. I now have Pro Comp Extreme Terrain radials in 15 x 10.5" Just no current pics of them. Removing the bias ply tires was the 1st thing I did to improve road handling.

out of interest, why have you removed the panhard? lots of people are trying to work out how to fit them, even SPUA.
The panhard bar was removed as it was contacting the leaf spring plate with suspension compression. As the springs settled, the clearance between the two lessened, and contact was felt, so off came the PH bar. It was limiting susp. compression to only about 1.5" Yes, I felt a little more "dartiness" with it removed than when it was in place.

Incredibly, that pitman arm is largely responsible for all the problems you're facing. It's obviously limiting compression travel and there's no way you can lower the car and maintain acceptable compression travel with it in place. A flatter pitman arm will be a must if you retain the 80 series steering box, but I genuinely don't think you can with sensible rim backspacing and a low car.
As mentioned, the 2wd toy truck pitman arm that I have and have not fitted yet, is flatter, and shorter. I will try it as I nothing to loose trying it. The only concern with trying it, is.... the drag link will be passing right under the 1.9TD crank pulley when the steering is straight ahead. Of course, this puts the drag link even further back to the oil pan edge somewhere when turns are made. This, combined with the flatter arm being even closer to the crank pulley may cause contact with the passenger side [ right ] suspension compression. I'll have to look closely to make sure the drag link and crank pulley won't hit.


As for the 2.5" backspacing, Thats not helping anything. A 0 to -13 offset (~3.75-4" backspace) is ideal and will help handling and allow the car to be lower because club radius is reduced. Obviously the reduced leverage on the front axle will be very helpful with the heavy Diesel. The 2001 rotors are too big and have inadequate offset to clear the well of 15" rims. You need 4 door Tracker brakes from a 1.6 MPFI car. These will clear any rim backspacing and the pads are basically the same size, however, ~4" backspacing will require you to move the shock hoops - the tire will contact the shock hoop at full lock/full flex.
Does the 2.5" back set wheel contribute that much to poor handling?? I got the rotors and calipers from a 2001 4 door Tracker, they are bolt on. The rotors are the same diameter as the oem zuk rotors, just thicker with cooling fins. The calipers have more mass, and the pads are prolly bigger than zuk too. 3.75" wheels "may" fit. I'll need to research this more.

I can see the clearance issues for an inside-the-rail steering box, but I can see interference between the spring and the sector shaft being an issue at full compression. an IFS pickup box will run outside the rail but has a rear facing pitman arm. Something to consider.
I have a toy IFS box, but went with the forward facing FJ box to make room for the panhard bar when I was planning this build from the beginning. Yes, it is mounted on the outside of the frame rail, like an FJ box. I've not looked into fitting it as a possible choice, or for possible clearance issues yet. Do you happen to know what guys do for a drag link when using one, with the spua configuration?
Also, a forward facing Chev Astro van box is an option. ZOR sells the box mounting plate for one. It, however, is an inside rail mounted box....not sure it would fit with my Acme rad. Dunno what steering linkage options are used with it.

As for the drag link, yes, you won't be able to retain the sky steering arm at all, it will put the drag link too high and it will foul the chassis once the car has been lowered. I can see at some point you've swapped the the rod back to the standard location and off of the sky arms. Good move - the Ackerman angle looks to be way out on the sky arms.
Yes, the ackerman angle is changed with Sky steering arms. Supposedly, not enough to adversely affect handling in sweeping corners, only at low speed hard turns, like driving in a perking lot. But, yes, I did put the oem zuk tie rod back on, as the Sky tie rod was hitting with suspension compression, so off it came.
So it appears that the main challenge [ for spua, with yj's in my case ] is fitting a steering box that will allow a drag link to connect to either high steer arms, or the oem zuk knuckles, or ? mercededes? arm. To be road legal here in BC Canada, steering components, like a drag link or pitman arm cannot be welded, other than by factory. It will fail a vehicle inspection if the inspector notices it. However, I may be able to get away with welding up the Sky high steer taper hole, and having a new taper hole machined, so the drag link can be installed from the bottom, thus giving more clearance between the drag link and frame upon susp. compression. Another option, is to machine the taper in the zuk knuckle to allow fitting for a larger FJ tie rod end, allowing me to make a new drag link. IF the new drag link "appears" professional and like it "could" be factory made, like a Sky or Low Range component, then an inspector could over look it. Otherwise......what are guys using for spua steering linkage in your parts?



Personally, I'd run toe at 0 with bias ply tires. toe promotes sketchy steering, but .125" should be OK.

OK, the missing links aren't helping anything. They're introducing more lateral movement in the axle. Replace them with proper, welded on shackle hangers.

In relation to jacking the chassis up and observing how much droop is in the springs, The idea is to determine how deep into the spring's travel you're running. I reckon you're not compressing them all that much at ride height. That's bad for ride quality and handling.
I'll do a check of this when I get time next week. As a guess, I'm only about 1-1.5" of spring compression with vehicle weight on them.
Any time I mention spring lift, I'm referring to compared to a factory standard Samurai.

There's no ideal spring lift for a particular spring, that's back to front. THere's and ideal height for the vehicle, which is as low as you can feasibly run. The task then is to build the car and choose springs that enable that. I'm suggesting that if you require 2" bumpstop spacing over standard to clear the sump, and you need to maintain about 2" of compression travel to maintain adequate on-road handling, you need about 2.5" of spring lift compared to a factory Samurai. you can de-camber or de-rate your YJ springs to achieve this, which will be a balance of maintaining adequate spring rate to support the diesel and prevent significant axle wrap and brake dive, but have a low enough rate to promote a good ride and get the car to settle deep into the springs travel.
How much spring compression in inches, by trying different yj leafs, should I aim for with the weight of the vehicle on them, at rest [ not driving ]? Even if i went to the oem "flat" yj springs with 4 pack leafs, I don't think spring compression will be that much with the vehicle weight on them, at rest.

A tracker steering box, 3" of spring lift and tracker PS box is a pretty common setup and everything clears well. However, as you point out, you're running the front axle a fair way forward. anything over 1.5" forward will create clearance problems between the pitman arm and the tie rod at full compression. I don't think a tracker box is feasible for you because of your radiator and engine, so lets stay away from that for now and rely on your 80 series box with a flat(ter) pitman arm.

How far you can pull the axle forward will depend on how far you're willing to get into the headlight buckets - with good flex and compression travel, a 31 will require some work around the front of the guard to clear.
I could also "pull the axle back" by replacing the oem zuk spring plates with aftermarket ones that have multiple holes drilled in them, for setting the leaf pin forward or backward on the spring plate. Moving the axle back 1" would then be possible.

That'll do for now.
Thank you!
Steve.

[Gwagensteve]

Quote:

I felt a little more "dartiness" with it removed than when it was in place.

Interesting. That's the opposite of what I would have expected. a panhard should, by reducing lateral axle movement, increase "dartiness" because it transmits small steering inputs much more faithfully. In a Samurai with soft leaf springs and a tracker power steering box, one turn of steering lock is absorbed in lateral axle movement. I'm suspicious that in your case the panhard was locking out suspension movement, perhaps because the roll centre clash between the SPOA and the panhard.

Quote:

The only concern with trying it, is.... the drag link will be passing right under the 1.9TD crank pulley when the steering is straight ahead. Of course, this puts the drag link even further back to the oil pan edge somewhere when turns are made. This, combined with the flatter arm being even closer to the crank pulley may cause contact with the passenger side [ right ] suspension compression. I'll have to look closely to make sure the drag link and crank pulley won't hit.

(This is making me dislike the acme conversion even more than I already did. If this is the bucket of compromises this engine choice pushes you towards, I don't consider it a workable conversion.)

OK, it's hard to see the relationship between everything from the photos.

You have to get rid of the sky arm and consider all your steering with the drag link connected to the tie rod, as per stock. You'll never lower the car enough with the drag link all the way up on the sky arm. Also, lowering the axle end of the draglink will lower the drag link at the crank pulley. (PS, is it the crank pulley thats the problem or the PS pump pulley - that looks lower in the photos- if so, can you move the PS pump?)

If you try and retain the FJ80 steering box, you'll definitely need to get the pitman arm up closer to the chassis to have any chance of missing the spring on compression. I can see that a shorter arm won't help engine clearance.

For reference, here's a tracker box installed with a tracker pitman arm on my car. the stud on the TRE almost touches the chassis.

Quote:

Does the 2.5" back set wheel contribute that much to poor handling?? I got the rotors and calipers from a 2001 4 door Tracker, they are bolt on. The rotors are the same diameter as the oem zuk rotors, just thicker with cooling fins. The calipers have more mass, and the pads are prolly bigger than zuk too. 3.75" wheels "may" fit. I'll need to research this more.

Low rim backspacing increases steering kickback on bumps. Whilst you aren't feeling it all that much in the steering, that force will be acting on the vehicle and pushing it around.

It sounds like the North American market used some different stuff - by 2001 our 4 door GV's all had brakes that won't clear 15" rims without caliper grinding and/or staggered pads, but they also have a different hat depth. It sounds like your brakes are the same as the 1.6 4 door brakes we got here, and they will clear any 15" rim. Here's my 1.6 ventilated brakes for reference. I'd deal with it as the last stop - the car will drive better with less rim offset, but at the moment it's not a deal breaker.

Quote:

I have a toy IFS box, but went with the forward facing FJ box to make room for the panhard bar when I was planning this build from the beginning. Yes, it is mounted on the outside of the frame rail, like an FJ box. I've not looked into fitting it as a possible choice, or for possible clearance issues yet. Do you happen to know what guys do for a drag link when using one, with the spua configuration?
Also, a forward facing Chev Astro van box is an option. ZOR sells the box mounting plate for one. It, however, is an inside rail mounted box....not sure it would fit with my Acme rad. Dunno what steering linkage options are used with it.

Yes, the LHD IFS pickup box would be helpful for us here in Australia so we can have a bigger box inside the rail, but I have seen FJ60 boxes used in a similar way to yours, but not with leaves, only coils. Using one with a stock style draglink would require custom draglink with a Toyota type TRE at the pitman arm. Locally, I'd use Coliso (he's on here) to sort this out - he offers HD steering links with uprated TRE's.

We like inside the rail boxes because tyre clearance is at a huge premium in that area when running low and with rim backspacing. I can see that that radiator is huge and will prohibit an inside the rail box.

Quote:

Yes, the ackerman angle is changed with Sky steering arms. Supposedly, not enough to adversely affect handling in sweeping corners, only at low speed hard turns, like driving in a perking lot. But, yes, I did put the oem zuk tie rod back on, as the Sky tie rod was hitting with suspension compression, so off it came.
So it appears that the main challenge [ for spua, with yj's in my case ] is fitting a steering box that will allow a drag link to connect to either high steer arms, or the oem zuk knuckles, or ? mercededes? arm. To be road legal here in BC Canada, steering components, like a drag link or pitman arm cannot be welded, other than by factory. It will fail a vehicle inspection if the inspector notices it. However, I may be able to get away with welding up the Sky high steer taper hole, and having a new taper hole machined, so the drag link can be installed from the bottom, thus giving more clearance between the drag link and frame upon susp. compression. Another option, is to machine the taper in the zuk knuckle to allow fitting for a larger FJ tie rod end, allowing me to make a new drag link. IF the new drag link "appears" professional and like it "could" be factory made, like a Sky or Low Range component, then an inspector could over look it. Otherwise......what are guys using for spua steering linkage in your parts?

Yes, reverse ackerman is helpful at low speed/offroad, I know a land rover guy who runs reverse ackerman and doesn't mind it on road. I still think it's silly. You won't ever be able to run a high steer arm with SPUA. 100% it will foul the chassis on articulation. You might be able to flip the taper, but you'll need to confirm it allows enough angularity on full flex.

We all use stock configuration. as noted above, there are HD options available, but there's no reason to overthink the linkages when they all work. My drag link is loose sleeved with pipe - I did this many years ago and that's all my steering has ever required, even with 35's and power steering.

Quote:

I'll do a check of this when I get time next week. As a guess, I'm only about 1-1.5" of spring compression with vehicle weight on them.

Golly, that's a stiff spring.

a RUF Samurai spring will sag about 5" into it's travel at ride height. Heres a photo from a million years ago of Gregc's old car. RUF with bumpstop spacing. You can see there's plenty of room for the pitman/drag link, maybe even yours.



and another photo from 400BC of the trolley tug at full flex showing the free camber of the OME rear spring.



I'd approach the problem something like this:

Make new front chassis ends with fixed shackle hangers to eliminate the missing link.
Clean everything off the chassis - bumpstop mounts, panhard mount, shock mounts.

Strip your packs to the main leaf only

Remove the truss and any added axle bracketry, including the sky arm.

Put the axle under SPUA.

Mock up a drag link to suit the IFS pickup pitman arm using the stock tie rod and and drag link location to the tie rod.

Cycle the suspension and see how much bumpstop spacing you need, and what you can move to reduce it. (like raising the motor, trimming the oil pan, moving the power steering pump. Run the stock front bump stops under the chassis rail. this will add flex without compromising axle/engine clearance.

Confirm you have retained 7˚ of caster

Mount the shocks. You can run these on top of the axle housing as we did with CJ's car using your existing hoops and retain tyre clearance.



Once you've landed on the minimum bumpstop spacing possible, then you can add leaves to the pack to achieve acceptable compression travel (circa 2" is plenty)

Then, you can get a machine shop or to make up a drag link that's the right length and configuration to suit the (I assume) toyota TRE at the box and the Samurai taper to mate with the tie rod.

Oh, a small aside - your rear traction bar is at a very hokey angle and will be creating a funky instant centre. It might be exacerbating the twitchiness in corners as you transfer on and off power in a corner. going back to SPUA will eliminate the need for it.

That's all for now, I need to go into the shed and work on my junk.

Steve.

[Gwagensteve]

Ah, just spotted your brakes in one of the photos. Yep they're the late style with shallow hats and won't work with more backspacing. (they're intended for 16" wheels)

Compare the depth of the hat to mine.

Steve.

[Spokerider]

Thank you Steve for laying out the steps to getting my zuk to spua. I would like to try and keep the Fj box, it it's possible. That means The Acme rad can stay also.
Are you suggesting that I toss the fj box and mount a toy IFS box? As you know, it too mounts to the outside of the frame and has a rear pointing pitman arm. Not sure if there's a benefit to this or not......tire clearnace wise and DL clearance wise.

As for making a drag link to mate with the zuk tie rod......not sure how to go about this. I could make it from DOM tube, with a FJ tie rod end threaded into the tube for the pitman arm hole. That's straight forward. Not sure about the one-piece forged hole end of the drag link, where it attaches to the joint there. As per our motor vehicle laws, there can't be any welding done to steering components other than factory. I would still weld if necessary, but only if there no other option, and only if the DL would still look to be "factory" oem to a vehicle inspector........who doesn't really know zuks inside-out.

What about using Chev one ton parts? I can get these and make a new tie rod and DL with these tie rod ends and TRE's. It would mean drilling out the zuk knuckle holes, and re-tapering to the Chev size. Not sure what taper and diameter they are tho. Would there be enough material on the zuk knuckles to safely do this? Ditto for the FJ pitman arm hole if I went with a Chev joint there too.

I have a post going on Zuwharrie. Rather than me type / post it all over again, will you please look to what I've written here?

https://bbs.zuwharrie.com/content?topic ... fo_1337823

Thank you for your advice and direction.

[Spokerider]

Oh yeah,
Does Coliso have a business? Sell steering parts?


"Locally, I'd use Coliso (he's on here) to sort this out - he offers HD steering links with uprated TRE's."

Thank you.

[Spokerider]

Forgot the Chev one ton parts link;

https://www.tmrcustoms.com/ca/steering/ ... kit-y-link

[pete_79]

Spokerider wrote:

Oh yeah,
Does Coliso have a business? Sell steering parts?


"Locally, I'd use Coliso (he's on here) to sort this out - he offers HD steering links with uprated TRE's."

Thank you.

http://auszookers.com/forum/viewtopic.php?p=910630#p910630

CONTACT:
sales@coliso.com.au

[Gwagensteve]

I’ll update in more detail later today if I have time, but from photos on Pirate it appears the 80 series steering box with a hilux pitman arm will work for SPUA, and the drag link will clear the motor with sensible bumpstop spacing if the power steering pump is relocated.

[Gwagensteve]

[QUOTE=Spokerider]


And a pic of when I was trying flat yj spring packs. You can see the fj box, pitman arm, and not much clearance between the DL and the vw power steering pump pulley.


[/QUOTE]

I think this photo from Pirate proves that:

A) The Hilux pitman arm will work - it will clear the spring on full compression and provide a pretty flat draglink angle once the drag link is dropped back onto the tie rod.

B) The PS pump pulley is in an unworkable spot.

Thankfully, PS pumps can be moved.

I think this photo proves just how hard that PS pump is making life for you.



Even if there was no feasible way to run a PS pump ANYWHERE else on the motor, I'd still discard it, and use an electric power steering pump like this: https://www.gumtree.com.au/s-ad/lonsdal ... 1197717605

If the shorter, flatter pitman arm pulls the drag link forward enough it will miss the oil pan, then I can't see any reason bumpstop spacing is required at all, so you can choose whatever ride height you want to provide adequate compression travel for your application (which might only be 1.5" over standard or so - those flat YJ springs would probably be fine once de-rated.

As for the steering, the TRE's used in the COLISO arms will solve your problem - the pitman arm end could be swapped to a TRE that matches the Toyota or you could sleeve the toyota pitman to suit the suzuki taper. Obviously your drag link will need to be longer than once designed for a stock steering box position.

I think that pretty much sorts the steering out, even in the worst case that you can't re mount the PS pump elsewhere.

The crank pulley can't be a problem - it's basically in the same place as it is in a stock Samurai, and it looks like the drag link is in front of the oil pan.

a photo of my car for reference.



With respect, I'm already following this across two forums, I don't want to do it across three - it won't change my advice. I've skimmed the Zuwharrie thread and I see there's lot of dubious advice on there, which is to be expected. If something significant comes up on there, I'm sure you'll let us know. The significant bit was the photos that show pan/axle clearance in a SPUA application. That's a little tight and I'd be modifying the pan if that was what I was looking a, but westcoaster still has acceptable compression travel and low overall lift.

Whilst I AM recommending basically starting from scratch, you're the one who wants to be happy and not want to redo it again in a year - How much time and money you've put into it to date is irrelevant if it's gone into the wrong things, and everything you've done to date has moved the car away from handling on road well, other than the panhard which you can't use. As it is, it looks like you can retain the radiator and steering box where they currently are, you can retain the springs, shackles, and probably retain the shocks. That's pretty much all the hard parts other than the useless missing link junk and the high steer that could never work SPUA. Sure, there's lots of labour in reworking it, but you've clearly already put a tonne of labour into it and you're unhappy, what's a little more to get a good outcome?

Steve.

[Gwagensteve]

As an aside, pan to axle clearance problems aren't unique to your setup

I'm notching my (tracker) axle housing to clear my (tracker) sump



but that's because I'm trying to get more compression travel and a lower static ride height than standard. I don't think I'll quite get there, but it will be close.

No amount of effort spent getting the car low is wasted effort. you can always add lift if the car is too low for your terrain, (it doesn't sound like you'll need to) but you're dealing with the opposite problem (As I was, with radius arms on top of the axle)

[Spokerider]

Thank you Steve.
And thanks for viewing the zuwharrie post. I wasn't expecting you to chime in, only hoping to give you a little more info without me typing it all out again.

As you can see, I research the shit out of things before I jump in. When I;m confident that I have a plan.....then I jump in. At least I can [ somewhat ] enjoy driving it after the 10 year build right now, before the tear down begins.
I'm pretty much there.
I'll assemble the new steering parts that I need........Coliso arms and tre's....I have no idea what they are or what they look like.....to see how they will fit my needs. I've also been looking at fj60 steering TRE's and DRE's and DOM tube to make new tie rod and DL. By reaming out the samurai knuckle holes to the fj taper, I can make the fj components work, with a Y type tie rod and DL design, just like the oem samurai design. Or.....I just need to find a way to lengthen the zuk DL, to mate with the fj pitman arm, without it looking like bubba fabbed it to a VI inspector.

I'll follow your advice on setting the suspension up with just one leaf, removing the shock towers, pan hard bracket on the frame, axle tube brace, and bump stops as suggested. I may try to move the vw PS pump......another on zuwharrie has done it and kindly shares his knowledge. More than likely, I'll be modding the oil pan too for needed clearance.
Do you have a preference for type / brand of shock towers? I do have some Ford F250 towers that guys have used for zuk shock spoa / spua mounting with success.

Thank you.

[Spokerider]

I jacked up the front of the zuk at the bumper and measured the amount of spring compression while at rest. The missing links just began to open at 3.5" of jack lift. So that be 3.5" of spring compression at rest.