[Zook_Fan]

So do you define the length by the width? Or the width by the length? When I'm thinking of a project I usually have very specific components that I want to make work.

Start with some known figures. You've decided on 37's, a fairly decent sized tyre and fairly heavy. How wide do you need them? You need to clear the chassis rails you choose, so what is your fundamental chassis. I believe you're thinking LJ just by the start of the thread.

37's being big and heavy need a decent diff. Hilux will work but you're on the edge of the strength. Cut down a 60 cruiser housing for the bigger centre and narrow width? CV's are at their limits.. Run 80 bells? Completely custom axles that you'll need spares for. Then you might as well run a fabbed housing because it will be straighter, have better clearance and stronger than a remanufactured stock housing.

What I'm trying to get at is everything is a package. You need to pick some things to start with and work with them. Different components are perfect for the application but just simply don't work with the rest of the configuration. Does this mean they are the component you should be basing the build around?

EDIT: Beaten with what I was asking

[Marko_SJ]

Well you know your way around the J series?

That meets a few criteria: Light, powerful, auto is doable right?

[tanshi]

haha, were getting too specific. and a bit beyond the scope of the thread.
i dont want this to be about my build or non build

[Zook_Fan]

If you already question the motor you won't like it there when it's done. You know there is more potential from that car with an auto and a bigger engine.

Why a 4 link front and rear? There's next to no link information on this site, let's get some flowing

[tanshi]

I havent really looked to much into link design as yet.
all that i have found lends me to believe 4 link both ends would lend its self to greater stability and balance front and rear. (i dont know this for sure)

yes there is more potential with the bigger motor and an auto, but it takes all the fun out of it if it doesnt ring ding ding

[Red89]

My theoretical build would be this which isnt necessarily small but is by TT standards :

105 WB
SWB Sierra body
Jimny 1.3 or Vit efi1.6 and auto
Custom diff housings for max clearance solid axle Lux width with Lux internals
Full hydro because its easier to package the shocks without a steering box.
5.14 TC and 5.29 Diff
4 link F + R
14 inch Air shocks
Sticky 37's

The only thing I may add would be queer steer

[Red89]

Zook_Fan wrote:

Start with some known figures. You've decided on 37's, a fairly decent sized tyre and fairly heavy. How wide do you need them? You need to clear the chassis rails you choose, so what is your fundamental chassis. I believe you're thinking LJ just by the start of the thread.

Most TT builds these days run 3 ft of original chassis and then the rest is tube placed where it needs to be for maximum clearance around other components, so chassis choice in comparison to tyre clearance isnt really an issue.

Zook_Fan wrote:

37's being big and heavy need a decent diff. Hilux will work but you're on the edge of the strength. Cut down a 60 cruiser housing for the bigger centre and narrow width? CV's are at their limits.. Run 80 bells? Completely custom axles that you'll need spares for. Then you might as well run a fabbed housing because it will be straighter, have better clearance and stronger than a remanufactured stock housing.

In a light, adequately powered buggy you can wheel the piss out of 37's all day every day with Lux diffs, Longs and Nitro R&P's no need to go any bigger, guys do it easily on 40's.

[tanshi]

sweeney had 40s and lux diffs with no issues.

as for width i think no wider than 1700mm
lj body is around 1200 wide so thats still 9 inches of tyre outside the body.

[Zook_Fan]

Red89 wrote:

Zook_Fan wrote:

Start with some known figures. You've decided on 37's, a fairly decent sized tyre and fairly heavy. How wide do you need them? You need to clear the chassis rails you choose, so what is your fundamental chassis. I believe you're thinking LJ just by the start of the thread.

Most TT builds these days run 3 ft of original chassis and then the rest is tube placed where it needs to be for maximum clearance around other components, so chassis choice in comparison to tyre clearance isnt really an issue.

I don't know the chassis configuration for the LJ, but for a sierra with the ruling of to the front engine mount the back of the front tyre at full lock would still be hitting standard rail unless you had the diff a very long way forward.

Red89 wrote:

Zook_Fan wrote:

37's being big and heavy need a decent diff. Hilux will work but you're on the edge of the strength. Cut down a 60 cruiser housing for the bigger centre and narrow width? CV's are at their limits.. Run 80 bells? Completely custom axles that you'll need spares for. Then you might as well run a fabbed housing because it will be straighter, have better clearance and stronger than a remanufactured stock housing.

In a light, adequately powered buggy you can wheel the piss out of 37's all day every day with Lux diffs, Longs and Nitro R&P's no need to go any bigger, guys do it easily on 40's.

tanshi wrote:

sweeney had 40s and lux diffs with no issues.

I thought that sweeney did have issues with his lux diffs? Both R&P's and longs. There is definitely an issue with king pins and steering arms but these both have upgrades available.

[JrZook]

tanshi wrote:

lj50 two stroke motor, (issue is no auto gearbox)

Wont be able to generate the wheel speed or punch required for "hopping" up large obstacles/ledges. Wonder how hard it would be to adapt a 200-300hp V6 2-stroke injected powerhead to an auto like a T700

[tanshi]

i was under the impression that he had no issues with lux diffs untill he went with the 42" pitbull tyres

[tanshi]

Zook_Fan wrote:

I don't know the chassis configuration for the LJ, but for a sierra with the ruling of to the front engine mount the back of the front tyre at full lock would still be hitting standard rail unless you had the diff a very long way forward.

LJ chassis is a good 100mm narrower than sierra

[Zook_Fan]

JrZook wrote:

tanshi wrote:

lj50 two stroke motor, (issue is no auto gearbox)

Wont be able to generate the wheel speed or punch required for "hopping" up large obstacles/ledges. Wonder how hard it would be to adapt a 200-300hp V6 2-stroke injected powerhead to an auto like a T700

I think want33's spoke about that a long time ago. Cooling is another issue after the adapting.

I can't host pictures where I am but people that have a loggin: http://www.rockracing4x4.com/forums/sho ... uggy/page6

That's sweeney's buggy with a long in pieces.

[Red89]

Zook_Fan wrote:

Red89 wrote:

Zook_Fan wrote:

Start with some known figures. You've decided on 37's, a fairly decent sized tyre and fairly heavy. How wide do you need them? You need to clear the chassis rails you choose, so what is your fundamental chassis. I believe you're thinking LJ just by the start of the thread.

Most TT builds these days run 3 ft of original chassis and then the rest is tube placed where it needs to be for maximum clearance around other components, so chassis choice in comparison to tyre clearance isnt really an issue.

I don't know the chassis configuration for the LJ, but for a sierra with the ruling of to the front engine mount the back of the front tyre at full lock would still be hitting standard rail unless you had the diff a very long way forward.

I havent read the regs properly in a while but I thought it was only 100mm in front of the firewall that was required or is that the B pillar ? Either way considering a build on 37's would be 100 inch plus WB your front diff would be over 12 inches forward anyway.

[Zook_Fan]

My sierra has the diff over 12" forward of stock and the back of the tyre would still hit.

I believe the chassis rulling is 300mm in front of the firewall or to the front most engine mount, which ever is larger. The rear can finish at the back of the cab.

[madmacca]

Great thread Tanshi

serious question tho , is this theoretical build to Win TT or just to compete ?

when I either rebuild or start again the major changes to my set up will be cutting brakes and disconnects , and a complete redesign of my front links .


if i was to start from scratch purely for TT my wish list would be
LS2 or LS98
T400
Atlas or hero transfer
shortened steering Mogs front and rear
16" racejackers
40" + stickys as a wish I would go for red lables BFGs
on probably another Vitt body

But and here lies the rub , building a vehicle for 1 event for me is not how i would proceed .
if I was to build again I would like to be reasonably competitive at both TT and RRR which although similar to the above has a few differences

LS2 or LS98
T400
Atlas or hero transfer
Dana 60 with dana 70 internals
16" coilovers and bypasses
40" + stickys as a wish I would go for red lables BFGs
on probably another Vitt body

not to say that the 2nd choice wouldn,t do well at TT (might have to retrain the nut behind the wheel a little )

[tanshi]

The “front” of the chassis must start at least 300 mm forward of the original firewall position ( ie. vertical section where brake master & booster mounts ) and finish “behind” the original B pillar on a 2 door vehicle and behind the C pillar on a 4 door vehicle

[madmacca]

TT regs also have a rule as to how far from the front of the motor the diff center line can be

[Zook_Fan]

Madmacca, that's a completely different machine. That second build with a 6L80 and ford 10" diffs would do well in so many different arena's. Including tuff truck. But either build would be big. Dana 60's and mogs aren't skinny. You did say shortened, so what width would you aim for?

Building a vehicle for 1 event isn't for me either, then I'd need too many vehicles!

[tanshi]

madmacca wrote:

TT regs also have a rule as to how far from the front of the motor the diff center line can be

yes but that just means that the diff has to move in conjunction with the engine. means moving the engine back too far gets stopped,

obviously i would like to do well, but its not really the be all and end all for me,

doing some thing out of the ordinary and surprising a few people along the way would make me happy.

Why the LS?
Why the atlas?
i know why the mogs but would like to get your why on them?

how much do cutting brakes actually help? arent there risks of front digs getting you disqualified in TT??

[madmacca]

would be looking for 2200 to 2300 wide at the wheels .

but after competing last year , and watching Taz in the OPW truck when i could .I know the downside to what I have now .

one of the biggest things I would have liked last year is more reduction or more torque at lower RPMs , maybe an auto would help that

fwiw my Vitt at the moment has
G16b std Vit manual g/box
6.5 geared sierra transfer
60 series front diffs running 5.29 ratio 1.5"spacers
4 link f&R
40"Treps

[madmacca]

tanshi wrote:

madmacca wrote:

TT regs also have a rule as to how far from the front of the motor the diff center line can be

yes but that just means that the diff has to move in conjunction with the engine. means moving the engine back too far gets stopped,

obviously i would like to do well, but its not really the be all and end all for me,

doing some thing out of the ordinary and surprising a few people along the way would make me happy.

Why the LS?
Why the atlas?
i know why the mogs but would like to get your why on them?

how much do cutting brakes actually help? arent there risks of front digs getting you disqualified in TT??

that i am aware of there are no penaltys for diggs , there is for rear steer

the LS as it will give me cheapish H/P

Atlas for strength and ratio availability . I like the look of the hero but it isnt commercially available yet
mogs for pumpkin height , and the extra gear reduction

in my opinion for TT cutting brakes would be invaluable . especially running a wide truck . seeing how some of the guys were using them last year opened my eyes
you would barely know that they had been used

anyway boss is looking at me , I will chat more here tonight

Macca

[tanshi]

i would like to hear more on your take of "watching Taz in the OPW truck when i could .I know the downside to what I have now "

having driven TT do you think that a narrower car would have any advantage with being able to drive around things? line choices? nimbleness etc?

[Jezza86]

tanshi wrote:

yes there is more potential with the bigger motor and an auto, but it takes all the fun out of it if it doesnt ring ding ding

13B single turbo, top mount intercooler?
<edit>i know its not the same as ring ding ding but BAPBAPBAP does get some serious underdog crowd support, its very light, it could be centred way back in the engine bay to keep weight low and centered.
its light enough to take a spare motor and you could go a small turbo to develop lower rpm torque. <edit>

[mnemonix]

No arguments here for the "smaller is better" concept. Sierras by design gain their ability from being small and nimble. Too many lose that edge when modified by upsetting the balance of wheelbase/track width/roll centre/COG.

However at TT the small truck will see you shine in the tighter track sections, but possibly be compromised in others where ramp-over etc are crucial.
Last year, some brilliant built vehicles were hungup on the simplest of obstacles because the truck before rolled a rock or chewed some dirt causing you to belly out.

The starting position you draw could make or break a small tyred, small tracked truck.

[tanshi]

the only real thing i can see an issue with a small built rig is the really steep bonus line climbs.

small narrow rig seems like it would be really easy to hold upright on side angles with a strap.

[Jezza86]

pilot and navigator. navigator can be in or out of the vehicle navigaiting.
so navigator = counterweight? sidecar style holding onto a exocage?

[tanshi]

navvie isnt allowed to tough the outside of the car when its in motion.

[Red89]

Jezza86 wrote:

pilot and navigator. navigator can be in or out of the vehicle navigaiting.
so navigator = counterweight? sidecar style holding onto a exocage?

tanshi wrote:

navvie isnt allowed to tough the outside of the car when its in motion.

Whilst Tanshi is correct, I have kicked my navi out in order to loose some 'unneccessary' wieght before.

[PurpleZOOK]

From what I've noticed at TT portals help with that little bit of extra clearance everything shaved and bash guards, around about 16" air shocks and around a 40" tyre like a trep or micky t claw, Main thing is clearance as most of the traps are large rocks that need a bit of speed to bounce.
Give matty white a msg his name is cut4b or bogga might be able to get onto him he competed a couple of years ago.
viewtopic.php?f=4&t=14551
"specs are 91 mod sierra
lux diffs 529 nitro gears dirty 30 axles creaper flanges
6 stud knuckels f&r hydro 6 inch dbl ended rams
40 inch treps rocktoy bead locks
6.5 transfer 5 speed box
1.6 vitara motor "