[jonno_racing]

ok there is a 3 and 4 speed yeah?
3 speed is non computer?
can a vit auto be made a stand alone easly? as in no transfer?
has any on adapted one to a g13?
are shifting kits available for either?

just running though some ideas of late and want to know i am correct before i think much further!
Phil

[ajsr]

the 3 speed is a gm trimatic, no computer
mine has been rebuilt using commodore parts, shift kits dont know

ask steve or joe about the rest

[canberramav]

You can adapt them to a 1.3 using what they call a lucky 13 adapter. Or you can make an adapter yourself obviously.

I have a lucky 13 adapter brand new in the box if you decide you want one.

[shep]

do the 3 speeds fit in a stock trans tunnel? and what is the gearing like?

[Fatzook]

shep wrote:

do the 3 speeds fit in a stock trans tunnel? and what is the gearing like?

Maybe with a BL, and with only 3 gears they are a little taller than 4sp gears, but you'll be revving very high on the hway as a sierra transfer has 20% more reduction thn a vit transfer in high range.

[joeblow]

You will have to do some stretching of the tunnel. gearing on the highway, if geared correct for tyre size, is very average compared to a vit 5 speed manual or a 4 speed auto. Pack some ear muffs.

[shep]

joeblow wrote:

Pack some ear muffs.

i already do

[ajsr]

shep wrote:

do the 3 speeds fit in a stock trans tunnel? and what is the gearing like?

with no body lift theres LOTS of trans tunnel streaching, trust me

[shep]

ajsr wrote:

shep wrote:

do the 3 speeds fit in a stock trans tunnel? and what is the gearing like?

with no body lift theres LOTS of trans tunnel streaching, trust me

i have a 25mm body lift. by stretching do ya mean belting with a hammer?

[Gwagensteve]

Jonno - I would have thought your setup would be fine with a trimatic.

Joeblow's point about road gearing is a bit faulty. If you gear the car correct for its tyre size... It's geared correct for it's tyre size. That's not "average."

Trimatics require tall diff gears though. Joe's preference to do nearly all the gearing in the diffs means he can't make trimatic's work on highway.

It's quite possible to run a trimatic with a 31" tyre and have cruise rpm at 4000rpm- which isn't much different to a stock jimny (and still have effectively 80:1 crawl ratio)- and I would have thought that would be pretty sweet with your GTI motor.

Obviously, if you up tyres to 33's (or bigger) then road RPM drops and more gearing options become workable.

You'll need 3.7's or 3.9's in the diffs, and look for the taller available transfer gears (so 6.4's with the 16% high range drop rather than 6.5's with 20% drop) or 4.1s.

The Trolley Tug build shows the jackshaft and tunnel work required:

http://www.auszookers.com/index.php?nam ... ic&t=14025

The AW-4 automatic is much longer - approximately 100mm longer than the trimatic. In my opinion, the transfer needs to be moved back to end up with a workable jackshaft length, which obviously adds to the work and cost involved - Three driveshafts need mods instead of just the jackshaft, and the tunnel needs to be opened up further back, in the vicinity of the front seat mounts.

There's no question the AW4 is a better auto, on and off road. It has a deeper converter ratio (2.4:1) and a lower 1st gear for off road work, along with a tall overdrive and a lockup converter for cruising. The tall overdrive allows the use of small tyres for road driving, and short diff gears like 4.6's or 5.12's.

AW-4's need some amount of wiring. You'll need the TCC from a vitara and you'll need to feed the TCC some inputs from the GTI computer. Should work though, but it will involve a bit of experimentation.

If you want to run small tyres and road drive regularly, the extra effort of running the AW-4 might be justified.

If you run larger tyres all the time, or do little road driving, then the trimatic is fine.

Another guide is how useful 5th gear is for you now. If you can't/don't pull 5th all that often right now, then you don't need an overdrive auto.


Steve.

[ajsr]

shep wrote:

ajsr wrote:

shep wrote:

do the 3 speeds fit in a stock trans tunnel? and what is the gearing like?

with no body lift theres LOTS of trans tunnel streaching, trust me

i have a 25mm body lift. by stretching do ya mean belting with a hammer?

mine has no bl so I cant say , but a hammer would come close. joe could tell you better

[Gwagensteve]

Driver's side maybe... Passenger side - I'd say no.









This is with a 2" BL.

[shep]

i want a auto

[kenn]

I got the AW4 in my LJ with a 2" body lift so anythings possible. I took 50mm out of the floor each side and widened the tunnel.. Joe does an adapter for the rear so you can run a Sierra transfer case, and if you look in my build thread there is a photo of my old jack shaft above the twin transfers short but no vibrations or problems in 6 years, the uni's were like new when i took it out ,must of just been built properly..

[joeblow]

Gwagensteve wrote:

Joeblow's point about road gearing is a bit faulty. If you gear the car correct for its tyre size... It's geared correct for it's tyre size. That's not "average."

Trimatics require tall diff gears though. Joe's preference to do nearly all the gearing in the diffs means he can't make trimatic's work on highway.

Funny that.....if you had taken 5 minutes to chat to me about the setup of my vehicle back in the club days you would have found that I was running 3.9 gears with the 3 speed.

I tried it with both 31 and 33 inch tyres. Highway revs were bearable....but come to any sort of hill and all the power would be sapped......fitting 4.6's or 5.1's to compensate for power would just mean the revs were at an awefull level due to the lack of overdrive. I then switched back to a manual.........then the best of all....the 4 speed auto.

Please take the time to talk with your fellow club members Steve...

Gwagensteve wrote:

If you run larger tyres all the time, or do little road driving, then the trimatic is fine.

Steve.

In fact, I would say thet statement should be opposite. If you want to run little tyres go the 3 speed....larger go the 4 speed.



And if you have a body lift you can use a hammer to stretch the tunnel.....it can be done.

[Gwagensteve]

I'll stand by my comments based on my experience thanks Joe.

Steve.

[mnemonix]

How reliable is the 4 speed auto once a bit of power is fed through it?
Ie: do they have known weak points?
Would have close too 300hp in front of it.

[jonno_racing]

i am asking this for my next build, id like 1600/gti boosted. but want auto. is it posible to manual-ise the 4 speed? im guessing 4 the 3 speed you can use a 2wd extention housing? rather than transfer?

[Fatzook]

mnemonix wrote:

How reliable is the 4 speed auto once a bit of power is fed through it?
Ie: do they have known weak points?
Would have close too 300hp in front of it.

The AW4 is completely upgradable. It has been used in dozens of vehicles and applications over the years.

Used in XJ Jeep Cherokee and early ZJ Grand Cherokee with 200HP up their ass, so with some minor work at a reputable auto shop you could make an AW-4 bulletproof.

[Gwagensteve]

jonno_racing wrote:

im guessing 4 the 3 speed you can use a 2wd extention housing? rather than transfer?

Do you read the trolley tug thread? You don't need an extension housing, you need a bearing support and seal on the back of the auto. The sierra jackshaft just plugs straight in.

You can make one, buy one from Trail tough or Joe, or fit a Datsun 180B rear wheel bearing into the 1" thick adapter between the auto and transfer and add an off the shelf seal.

Steve.

[shakes]

So how tolerable will a 1.3 carby motor, with the 3speed, NT diff's (3.9's?) and 6.4's be with either 31" or 33" tires at both 100kp/h and take-off?

Off-road I assume it will be very driveable?

[Fatzook]

shakes wrote:

So how tolerable will a 1.3 carby motor, with the 3speed, NT diff's (3.9's?) and 6.4's be with either 31" or 33" tires at both 100kp/h and take-off?

Off-road I assume it will be very driveable?

That would be the very definition of 'unbarable' IMO.

Go take a 1.3L auto barina for a spin. Then imagine having 20kw less and a 4wd drivetrain.

[JrZook]

Fatzook wrote:

shakes wrote:

So how tolerable will a 1.3 carby motor, with the 3speed, NT diff's (3.9's?) and 6.4's be with either 31" or 33" tires at both 100kp/h and take-off?

Off-road I assume it will be very driveable?

That would be the very definition of 'unbarable' IMO.

Go take a 1.3L auto barina for a spin. Then imagine having 20kw less and a 4wd drivetrain.

They are pretty gutless!

[shakes]

Damn. Engine conversion will come sooner rather than later I'm guessing.

[Fatzook]

shakes wrote:

Damn. Engine conversion will come sooner rather than later I'm guessing.

Yeah I'd hae to drive a carby 1.3 auto sierra on road. It would suck!

I'd even go as far as to say that an auto G16B leaves you wanting for power on road. Off-road though.....fantastic!

[shakes]

Fatzook wrote:

shakes wrote:

Damn. Engine conversion will come sooner rather than later I'm guessing.

Yeah I'd hae to drive a carby 1.3 auto sierra on road. It would suck!

I'd even go as far as to say that an auto G16B leaves you wanting for power on road. Off-road though.....fantastic!

I figure anything with lowish torque and big tires will feel sluggish. Now to decide if I want an auto bad enough to do an engine conversion

[Fatzook]

shakes wrote:

Fatzook wrote:

shakes wrote:

Damn. Engine conversion will come sooner rather than later I'm guessing.

Yeah I'd hae to drive a carby 1.3 auto sierra on road. It would suck!

I'd even go as far as to say that an auto G16B leaves you wanting for power on road. Off-road though.....fantastic!

I figure anything with lowish torque and big tires will feel sluggish. Now to decide if I want an auto bad enough to do an engine conversion

Do it at the same time as a G16B. Not worth it otherwise (IMO)