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Tim.flatfour
01-08-2006, 12:35 PM
Hello everyone, this is my first post but I've been browsing the forums a bit for the past two days. I was hoping to find some help with this project idea I have.

Recently I've been planning out my first big project car, a mid-engine US-Spec Subaru STi powered '71 Beetle. I know the first step to a project like this is to find a basis, and I found a person that makes designs for a mid-engine V8 Beetle. Here is a link to his web page- http://www.rorty-design.com/content/beetle.htm I've presented my idea to him, and he likes it. He said he would be willing to work with me on this project if I can figure out a transaxle solution and take the measurements needed. I've already began doing the research, but on to what I need help with.

Like the title states, I'm a beginner. I've never done anything like this before, only basic engine, suspension, and body work. Does anyone have any words of wisdom to bestow to my situation? Is there any decent literature to help me better understand all the aspects of a project such as this?

Any help given will be greatly appreciated.

John Kelly
01-08-2006, 03:17 PM
Hi Tim,

A Porsche 914 transaxle and rear suspension might be something to consider. I was going to do this in a Ghia but have since changed my mind. Have you checked out:

www.shoptalkforums.com

www.thesamba.com

www.914club.com

http://www.franklinsvwwerks.com/phpbb/

John www.ghiaspecialties.com

Tim.flatfour
01-08-2006, 03:22 PM
John, I hadn't considered a 914 transaxle. What would be the benefit of using it?

I'm a member on Shoptalk and The Samba, as well as germanlook.com and superbeetlesonly.com.

Peter Miles
01-08-2006, 04:02 PM
With mid-engine transplants, engine crankshaft rotation versus mounting in front of or behind the rear axle are always possible tradeoff options.

I don't know whether any of the aircraft guys that are using Subarus have come up with reverse rotation setups for the engines.

Sometimes, pinions and ring gears can be changed for a set that expect rotation in the opposite rotation.

I once used a Corvair transaxle with a Chevy V-8 in a tube-framed Kelmark kit car. The Corvair was a rear-engine car, so rotating the transaxle 180 degrees for use in a mid-engined installation had everything rotating in the correct direction without needing to resort to any reverse-rotation components.

Good luck with your research and your project!

Tim.flatfour
01-08-2006, 04:18 PM
I hadn't planned on rotating the engine and transmission so I shouldn't run in to any such problems, correct?

seasalt
01-08-2006, 08:10 PM
I think ppl used to turn VW diffs upside down to use in mid engine layouts, to get the driving wheels turning the right way. (otherwise four reverses and one forward.)

I'm not very familiar with Subaru motors, but one course of action would be to take the whole motor, gearbox, and wheels out of the front of the Subaru, and mount them in the rear of the VW. No idea how feasible that is.

Another is to mate the mid-motor to an inverted VW diff. The 914 diff was suggested because it is from a mid engine vehicle.

If it was a v8 conversion, ppls use Porsche 911 rears (inverted?) to take the Hors(ch)e Power.

Gonejunking
01-08-2006, 08:59 PM
Hi Tim
This should be an easy transplant. You'll have a time building the shift linkage, but everything else is a drop-in and weld.

I did a conversion like this with an EA 81 engine.

Tim.flatfour
01-14-2006, 12:57 AM
Seasalt, I was thinking of doing exactly that. I could use the Subaru FWD transmission which mounts to all EJ series motors with no problem. The problem I'm facing now is the distance between the motor and the axles, where the rear suspension will be installed. There is only about five inches of clearance there. Here is a CAD drawing that may help anyone trying to picture this-

http://img167.exs.cx/img167/7427/beetlechassis029qc.jpg

I sent an email to the designer to get the dimensions of the V8 and tranny used for this design so I can see if the EJ motor will fit.

edwardd_
01-14-2006, 08:50 AM
Tim,


Is this a Rorty chassis design?

TIA

kenb
01-14-2006, 10:38 AM
I think ppl used to turn VW diffs upside down to use in mid engine layouts, to get the driving wheels turning the right way. (otherwise four reverses and one forward.)


It's been twenty years since I was last working with the VW stuff, but I recall that it was a simple job to flip over the diff & crown gear within the transaxle casing so that it rides on the opposite side of the pinion gear, thus solving the rotation problem. Several of the guys I raced with built mid-engine dune buggies this way, and they simply installed the whole transaxle backwards (right side up) at the back of the frame. I know this can be done with the stock Beetle & VW bus transaxles, but I'm not too sure about the Porche units.

Cheers,
Ken

Tim.flatfour
01-14-2006, 11:45 AM
Tim,


Is this a Rorty chassis design?

TIA

Yes it is.

bhj
01-14-2006, 02:57 PM
In the early 90's I worked at a car lot that took in on trade a beater 914 with a SBC motor conversion. If memory serves me, it used the 914 transaxle and an adapter plate. The car would eat clutches, I think the clutch used a stockish disc, not sure on the pressure plate. It was a very fun car to drive with a new clutch. Very likely the fastest car I've ever driven.

doug_walter2002
01-14-2006, 10:42 PM
A friend of mine is building a mid eng. 34 ford roadster with a small block chev with a porsche 911 transaxel upside down and backwards.

doug_walter2002
01-14-2006, 10:47 PM
sorr I punched send before attatching the pic.