Noy a GT40, but trans advice appreciated!

[Andy S]

Hello everyone!

Sorry, I don't have a GT40 (although I'd love one one day...).

I'm building a mid engined spaceframe chassis to house a chevy small block for a road going '64 VW Beetle project, but I don'y have thousands of $£$£ to spend....

I have read lots of differing opinions about transaxles and I'm still al little confused.

Space isn't an issue.
Cost is an issue.
The car will weigh approx 2200 lbs.

I will be using either an LT-1 motor or similar crate engine 300 - 400 ft/lbs torque max.

I won't be hammering it, but need the trans to cope with the occasional dumped clutch start at the drag strip without breaking....

My questions are:-

Is there a cheaper alternative to the G50 trans?
Are any of the Audi trans strong enough for my application?
If so, which ones?
If not, are they expensive to modify?
Any one used a Mendeola?
Has anyone used an inverted C5 corvette trans?

Sorry for all the questions, but you guys seem to be the most experienced in this field as your application is similar to mine.

Many thanks in advance.

Andy (UK)

[Lee]

Hi Andy
Please take this in a positive manner. But have a look at the titles of the first page of posts in this section and you'll see most of the options mentioned just there.

Have a search through for each of them and you'll find more info than you will know what to do with. The search button is across the top of the screen, below where it says 'Welcome, Andy S'. Try to keep the search simple and you will find plenty.

Inverted C5 transmission? Haven't heard that one before.

If you are planning on building from scratch, can I respectfully suggest, based on your 2 questions so far, that you think again? Building a car from scratch will take more time and effort than I suspect you could possibly imagine.

Good look in finding a chassis already made into which you can drop the engine/ gearbox combo that the builder designed it around.
All the best

[Eric A.]

If cost is an important part of your decision the Audi 016 is probably your best bet. With the improvements mentioned on several threads here it will handle alot. Even the G50 will have trouble with clutch dump starts, I suspect. The Corvette is too long as the differential is behind the transmission. It doesn't need to be inverted but it doesn't have any provisions for a clutch as far as I know. The Mendeola transaxles are pretty pricey if you want to go that route although they have some strong units. I would find an 016 and install the reinforcing plate and a 944 turbo differential with the 3.22 R&P from German Transaxle and drive it with respect.

[Ron Earp]

Andy,

Isn't the Corvette C5 transmission setup for a torque tube? If so, then it'd need some work to mate directly to the back of a Chevy small block.

As mentioned, if setup behind the motor it would not need inverting. If setup in front of the motor it would.

You might want to have a look at Kennedy Engineering, they offer adpaters for many transaxles and motors.

http://www.kennedyeng.com/

Order early, about two months before you even think about needed it. They are very slow.

Ron

[Pete T]

The c5 t56 transaxle is quite large and would put the output shafts very far back. I would also think that the cost would be unreasonably high. I aggree, the 016 with modifications would be a good choice.

Here is an image(if it works)

[Lynn]

Pete, et al,

I have often wondered what one of these 'vette transaxles would do for the balance of some front engine/roadster cars like a cobra, Jag XK120 or the like.

Regards,
Lynn

[Andy S]

Thanks for your replies, must be rather tedious to advise a none GT40 owner.

Looks like the Audi unit is the one to go for then.

I am reasonably skilled in terms of fabrication and welding so actually phisically building the chassis holds no fear for me. Unfortunately, no-one makes a mid engined chassis for the Beetle, so I have to work from scratch. The real headache will be figuring out all the suspension geometry - tricky, but not impossible.

Thanks for your advise.

[Howard Jones]

Build a jig for the stock VW floor pan. The start modifing the Jig to take your new power train, suspension, cooling system etc. The rest is going to be your homework.

Good luck....

On second thought how about a 914? Lots of them have been done with a mid engine V8.

[Jac Mac]

It,s not that its tedious Andy, if you spend a couple of hours one night checking thru the T/Axle tech you should find that even the GT40 replicas have a few variations. With your setup the dimensions of the VW are going to dictate what you can use etc.

As to your project, I spent an interesting evening with a guy in West Australia, in 1981 who had a 327 in the front of a VW beetle that he had muffled to whisper jet standards. He still had the 1200 VW in the back running,but not hooked up to a trans. You can imagine how much fun he had at every set of lights with this setup. It think it had a Muncie Trans & shortened Jag Diff. Looked a real sleeper with VW hubcaps etc.

Jac Mac

[Andy S]

Cheers...

It's an interesting progect.
I love air cooled VW's and have restored them before.
I love drag racing.
I love V8 muscle and have owned several Corvettes over the years.
I love mid engined high performance cars, I was lucky enough to own an Anniversary Countach some years ago when I had some cash.

The mid engined V8 Beelte seems to scratch all the itches in one go!

The plan is to have fairly stock body work, lowered and maybe some Centreline wheels and a roll cage. Sort of 'sleeper with a hint of mystery'.

One area you guys may be able to help me is with the cooling.

I have a few trains of thought that you may be able to comment on?

1) Have a big rad up front with a scoop under the front valance - a bit like a C4 'Vette. - I hate this idea, but it will work....

2) Have two large scoops/NACA ducts/grills etc in the rear quarter panels in front of the rear wings with a radiator in each side - bit like a Countach

3) Have the same ducts/grills as above, but mount one bigger rad where the rear bulkhead once sat, beneath the rear window, above the trans. This option might not be efficient, as the rad will get all the hot air from the headers etc too...

Any thoughts?

Ta.

[Jac Mac]

Andy, The MISS/KISS [make it simple stupid/keep it simple stupid] principle applies here.[Im not calling you stupid, just acknowledging that I may have been in the past].

'No1' would appear to be the most simple, 'No2' will require more plumbing& subject to air locks etc.'No3' would probably require a lot of fan assistance.

Two back yard tip's to help you get started;
The Air inlet area to the radiator usually only needs to be 1/3 of the radiator area[ rad-3'x1'--- inlet1'x1'/2'x6" etc] Exit area should be as large as possible.
Since your using a VW, make up a couple of simple U-tube manometer's out of plastic tube/ with water & food colouring to check out the hi/lo areas on the car at various speeds. A couple of hr's spent doing this could save a lot of wasted effort later.

Jac Mac

[Lynn]

Andy,

Actually there is a guy who is a member here who DOES build midengine chassis with VW dimensions. His name is Eric Martin and he lives in Dallas. He is the principal for A & E Automotive. He was the second respondent to your initial post.

Send PM to Eric Martin

Regards,
Lynn

[Andy S]

I'm suddenly very excited!

I love the look of that chassis - especially as all the suspension design & geometry looks to be sorted....

I wonder if there are plans or any dimensions available, or anyone who owns or has built it with valuable experience?

Wow - what a gold mine find - thanks, I'll mail him now.

Oh, by the way, that manometer idea sounds excellent! Just so I fully understand, please can you clarify how you would use this device and collect the data - what dia tube, what dimensions, angles to flow etc?

[Andy S]

Just a though - has anyone ever used a Subaru Impreza trans. Surely they must be very strong to take lots of turbo torque and rally abuse?

[Jac Mac]

Originally Posted by Last Triumph

Just a though - has anyone ever used a Subaru Impreza trans. Surely they must be very strong to take lots of turbo torque and rally abuse?

Just a thought, have you compared the 300/400 ft lb of torque that your crate engine will probably have @ around 4000/4500 RPM to the torque the Subaru produce's at the same RPM. Then did you not say you wanted to be able to do some drag race type starts? I think this combination might not be compatible!

The manometer I mentioned is a length of 1/8" bore plastic tube formed & fastened on a piece of whiteboard in a 'U' approx 18" high. one end is open & the other fixed in the area you wish to check for pressure difference. Place this end in a potscrub or open cell foam for a steady reading. Now hang your 'U' manometer off the car dash where you can see it and fill with water that has some food colouring added until approx 1/2 way up the 'U'. Mark this level with a marker pen. Now go for a drive and note the readings obtained.
If the level in the open end drops you have a 'low' pressure area, if it rise's you have 'high pressure'. Try to do the testing in calm conditions and away from other traffic etc.

Jac Mac

[Andy S]

I'm with youi now re the manometer... great idea.

Some of the Impreza are pumping out well over 300 bhp with turbo torque to match. They are built for abuse and enjoy Jap reliability.

It was just an idea.

Obviuosly it's not a good one or we'd all have Scooby 'boxes in our cars...