Transaxle conversion

[Lewis]

Hey, anyone ever thought of trying to engineer some sort of system to be able to put a manual transaxle on a 1UZFE equiped car (or anything else for that matter), would be an excellent way to get better weight distribution. Any ideas?
Cheers,
Lewis

 

[Zuffen]

Lewis,

Do a search.

Rivmast is using a Renault UN1.

Lambo may be using a Porsche G50 or Audi transaxle.

Skid is using the Porsche (Audi) 944 box.

Autronic started with a Ford Siera and has (I think) swapped to a Nissan GTR box.

Plenty of options.

 

[rivmasta]

Actually UN1's can only handle up to about 200 ft/pd without mods. UN5 is the way to go for Renault.

Our setup is: UN5 bellhousing adaptor to 1UZ bolt pattern. Custom sprung 4 puck feramic clutch, custom flywheel, hilux H/D pressure plate. Mods include aftermarket diff, crown & pinion, all 5 gear sets (shorter ratios, bigger gears), bigger input and output shafts and porsche 930CVs, rebuilt with new bearings. Total is 10K Aus, weight is apporx 60+kg.

Adaptors available in Aus for Porsche G50/50, VW (dont do it!), Renault, Audi.

Race options inlcude Fortin, Mendiola or if you want to get real serious, Albins (now available in dog-geared 6spd, full sequencial).

 

[skid]

Hi,

I'm mating it to a 944 so needing an adapter to the torque tube and the transaxle is about 1.5m further behind.

To be honest the transaxle isn't that big (though it is a bit long) and I guess it could fit in the void normally occupied by a diff. Undoubtedly there would be a bit of body or fuel tank in the way but I would guess it's not insurmountable. Drive shafts would probably need bastardising between the 2 formats but again not impossible.

A knackered old 944 can handle a fair amount of horses (Renegade convert 944's with Chevy SB and LT1's I think) and the box appears ok. I've sourced a turbo with LSD which reportedly can handle 550+bhp in a 944 so going to hopefully test that theory! ;o)

Cheers

Mark

 

[rivmasta]

Interesting stuff!

Ive got a mate who is in the planning stage of a build of a front engined buggy and was looking for a similar setup to this. I'll put him onto it.

I know of alot of cars that run 20valve 4AG's into SR20DET gearboxes then into either Jag or Commodore diffs with inboard brakes etc.... but the 944 option seems to be better for weight distribution, not to mention lighter anyway.

Good luck!

 

[Lewis]

What about a Porsche 968 box? Would it be able to handle high numbers similar to the supra 6spd (forgot the technical name)?
Would you guys see it as being feasible in a soarer/sc400, or not worth the effort?
Just thinking out load
Lewis

 

[skid]

What about a Porsche 968 box? Would it be able to handle high numbers similar to the supra 6spd (forgot the technical name)?
Would you guys see it as being feasible in a soarer/sc400, or not worth the effort?
Just thinking out load
Lewis

As per my post above the 944 family of boxes are very strong as Renegade in the US do Chevy SB conversions on the 944 on the basic standard 5 speed box.

The strongest and best suited to the extra V8 power is the LSD 5 speed Porsche Turbo box (Porsche 951) and I believe the Turbo S is slightly stronger still with stronger 1st and 2nd ratios.

The 968 is an enhanced 944. Also please note the Marheteers dream of a 6 speed box made everyone think it was a 'must have' to ditch their 944 and buy a 968, but indeed from the research I have done the 968 6 speed is not as strong as the 944 5 speed LSD.

MORE NUMBERS DOES NOT EQUAL BETTER!

So if you can pick up the turbo LSD transaxle plus the torque tube, front bell housing, clutch and flywheel and the drive shafts and I reacon with a bit of head scratching and some ingenuity you could create a brilliantly better balanced car.

M

 

[cribbj]

The G50/50 is the strongest of the Porsche 5 speed transaxles and it was only available in the '89 model Turbo Carrera. Probably the strongest box of all was the 930, but it's only a 4 speed.

You can't touch either of these boxes for less than $7,000 to $8,000 USD these days, because people know what they're worth. Plus, Ultima Cars, Ltd has been buying every one that comes up for sale in the US, and bringing them to the UK.

I bought a G50/03 with LSD recently for my GT40 project. This was out of a '91 911 and it isn't as strong as the 50/50 or 50/52, but I still had to pay half the going rate of a G50/50 for it.

For a V8 application I think Skid is correct, you don't want one of the 6 spd Porsche boxes - remember Porsches make their power up high, but they're not torque monsters down low. The ratios just aren't right with the 6spd boxes, nor is their torque handling capability. The combination of a supercharged V8, a dumped clutch, and sticky tires would probably blow one of these boxes a lot sooner than the 5spd boxes.

If you're interested in Porsche transaxles, have a look at Rennsport, Powerhaus, and Renegade's sites. There's good info on all of these.

John

 

[Lewis]

Thanks for the info guys, will definitely look into it more closely, even if nothing comes of it, I'm sure the extra knowledge will be used at some point....or maybe not haha.
Cheers,
Lewis

 

[Toysrme]

An actual trans-axle? FWD? Toyota (asian-Warner) has many strong trans-axles.
The entire E FWD type (E-52, E-53 from mr2's, E-152, E-153 from Camry platform) With a good clutch can hold a good 550ftlb without being cracked open.

There are LSD's avalible from the factory MR2's, Kaaz makes LSD's, and you can machine quafies in there if you can find one.

Axles stock can be finiky around 400bhp+, but there are aftermarket axles in MR2 use taking well in excess of 800bhp.



See, ya don't have to go outside of Toyota to get good transaxles.
For A/T's (outside of this discussion, but just for future refferance) the A54X (Camry v6 platform until 02) series can be built to hold in excess of 650bhp.

 

[Lewis]

No, Toysrme, I wasn't suggesting for a fwd application. Was thinking rear transaxle for front-engined vehicule like the sc400/soarer, ls400 etc...etc...
Speaking about Porsche transmissions what about a 928 5 speed? Wouldn't it be even more suitable since it was made to handle the Porsche V8?
Keeping this discussion going
Cheers,
Lewis

 

[rivmasta]

Did the 928 run a torque tube to transaxle arrangement? I though it was a standard gearbox tailshaft independant diff setup in the 928?

 

[Lewis]

Nope it was a torque tube to transaxle. Checked just incase
Lewis

 

[rivmasta]

well slap my arse and call me sally, I thought it was conventional.

Actually, dont call me sally. Thats weird.

What size CV's & axles does it run? Anyone have any idea of the general overall weight difference between torque tube/transaxle compared to gearbox/tailshaft/diff?

 

[sloshua]

The 928 used a REALLY tall final drive. I think the options were 2.25 and 2.75

 

[skid]

just edited my post as it was shite! :redface:

 

[sloshua]

Not sure about the 944, but the 928 looks like the above pic, torque tube and all.

 

[steveo]

Another option for those interested might be the transaxle from Alfa-Romeos.
Milanos (type75), Alfetta GT's and Alfetta Coupes use a transaxle with inboard brakes. The clutch assembly is located at the engine (front engine) in the bellhousing. These boxes, like the Porsche 928 box is long and fairly slender, but does not use a torque tube to connect the engine and gearbox (uses the chassis). These boxes may not be easy to find, but they are pretty strong.

Just another option to muddy the water.

 

[Lewis]

Anyone have any info on the 928 box? Limits etc...?
Cheers,
Lewis

 

[podge]

ive been looking at the audi 016 transaxle, for the price and reading i dont think you can go much wrong ive been trawling the gt40 forums for info and it apears the 944 turbo box is the audi 016