Hey guys, just lookin for some gearbox info.
Im doing a manual conversion on a TPI350 Transam. In my experience the T5s are waaay too weak and the T56 and ZF boxes are reeeeally expensive here.
Im thinking of using a Getrag gearbox out of a Supra in my project, anyone heard of anyting like this done before? Any suggestions howto go about it. Im thinking a custom adapter plate will be needed, other than that theyre super-strong and have a beautiful shift.

Thanks

 

I think that by the time you fab one up to work you could have paid for a T56. Since you are in the land down under see if you can buy one from Holden? GM should have trannies down there.

 

Yeah why are T56 so expensive down there? There should be an abundant supply, don't lots of Holdens and other come with them.

 

If the 6spd Monaro's use the LS1, don't they use the T-56, or do they use the ZF-6spd?

The 04' GTO"s pretty much the same car, but it uses the T-56 last I heard.

 

LS1 holden cars use the t56.

 

I was pretty sure they used a T-56, but I didn't want to make a definitive statement until I knew for sure.

 

Hey mate. I don't believe there was a T56 in your country with the same front end (input shaft / front cover / bellhousing) as the LT1 f-bodies here, so that sucks.

What's the costs of the T56 from a Holden vs. the Supra Getrag? I would think that by the time you're done modifying for the Getrag, the T56 would have made more sense. Such as: LS1 T56 + McLeod bellhousing = easy.

More info on the Getrag would be helpful too.

 

Yea i had a look around and it seems ill have to get some custom work done for either t56 or the Getrag so its gonna cost me either way!

The T56s are used in the Commodores/Monaros here since the LS1 is so bludy common so theyre in great demand by everyone from manufacturers to repairers to aftermarket.

The Supra boxes are rated at about 550hp similar to T56 but have a much nicer feel and shift (in my experience anyway). Theyre about AU$500 whereas youll be lucky to find a T56 for less than AU$2000.

Funnily enough, i couldnt find anyone doing conversion kits or bellhousings for the old 350s, only for the local Holden 308s and other common engines. Everyone here seems to stick to auto trannies, ive never seen anything but TH350s and TH700s.

 

Have you considered aftermarket transmissions? Richmond makes some good ones, 6 speed rod, 5 speed TKO, and even 4 speed Super T10's. Also maybe look into G-Force? They can rebuild the T5 to handle up to 600hp and you wont need to deal with any type of conversions.

 

Yea the only aftermarket trans around here are the Tremec TKOs and theyre about the same as a T56 (not sure). I know the T5s can be rebuilt with strengthened internals but seriously wat for? Ive driven 86, 96, 00 and 03 model cars that came with T5 from the factory and theyve all been shocking. Break too easy, too many problems, clunky shift, etc.

To be honest ive got my heart set on a Supra box, they can handle the big power and if youve ever driven one youll understand the better shift quality.

Im actually gonna use the transam as a drift car so a good clean gearbox is essential. I hear "Drift" is going off in Hawaii as much as it is here.

 

I thought you can't use an LS1 T56 on a gen I/II small block, only the LT1 T56? Or is that only the Corvette LS1 T56 I'm thinking of?

 

You cant, people here have to use adapter plates or different bellhousings. All the parts can be had in "conversion kits" that a number or reputable auto shops sell. Id think you could find much cheaper deals over is U.S.

 

Is your TA right or left hand drive? I remember seeing an article in Hot Rod many years ago about a guy who was converting old muscle cars to right hand drive so they could be street driven down under. How did you get your car there and what is required registration wise?

 

All road-registable T/As here are RHD. Im havent purchased the car yet, still looking for the right deal. It pays to know the car before you buy it

Ive tried every importer in my state (Victoria) and noone wants to touch f-bodys since theres a pretty small profit margin. And same goes for newer cars like 4th-gens Firebirds and Camaros, id probably be paying around US$40,000 minimum for one but the stupid government brought in new import rules making it veeeeery difficult to import cars that are less than 15 years old. You have to put a same model car through crash tests to prove ADR (Australian Design Rules compliance) as well as heaps of other uselss crap. Theres a few places that do RHD conversions that costs 5000-15000 so its not cheap playing with an f-body here hehe.

My plan is to buy an unloved Firebird and throw some T/A panels on it and do a manual conversion.

 

You can; just need the McLeod bellhousing / scattershield & adapter plate. Nothin' to it.

 

Thanks T Terror.

 

An adaptor plate would only adapt the bell housing to the block.

You would need some way to pilot the input shaft & put the flywheel at the proper axial location wrt the input shaft. Since you'd almost definitely need a custom flywheel, you could design the flywheel to accurately pilot off the crank, and use the flywheel to locate the pilot bushing for the input shaft (just make sure that whatever runout you end up with will be tolerated by the transmission), and put the clutch assy in the correct axial location with respect to the trans, accounting for the adaptor plate thickness as well. I think you can get a starter ring separately and press it on your new flywheel. Hopefully the new trans' bellhousing will accomodate a flywheel large enough to be engaged by the starter, otherwise this could be a showstopper. Depending on how different the overall geometry is , the flywheel could get ugly (i.e. large, heavy, and expensive).

You would need to figure out a way to adapt the clutch linkage. Presuming its hydraulic and will/can be made to fit the car on the trans side, whether push/pull style release, etc. it may not be too hard--might be able to mix and match master & slave cyls with a custom line made to your specs at a shop that deals with hydraulics.

You'd need to fab up a way to locate the torque arm.

You'd need a new drive shaft with the proper yokes.

The transmissions size, shape, rear mounting point, and shifter location would need to be taken into account as to whether or not it would fit the car, how hard it would be to make it fit the car (include interior in the analysis), and whether or not it will be worth it to you in the end.

I think thats all, I'd look over the whole project, identify any if any potential showstoppers will indeed be an issue; if not, then proceed to examine every aspect of the project down to the last detail, especially for cost of every single piece you'll need (i.e. create working drawings for the custom pieces that will need to be farmed out & price them, price all raw materials, the trans, driveshaft, linkage, etc and make sure every issue is addressed).

If most of these issues can be resolved simply and the trans is as good as you say, then this would be pretty cool, but definitely not if done strictly in the interests of saving money.

Good luck, but keep in mind a complete LS1/T56 combo might be easier and has been done with relative ease (of course, I don't know what the GTO/Monaro accessories look like, but thats another can of worms)

 

Yea thanks for that 377Z, very detailed, very helpful. ive got the general idea of how things would work out, but im stuck on the details and specifics.