I just had an interesting idea...what about using a Beetle transaxle and rear swingarms for a simple IRS setup? Or would the tranny be too big? Hm....

been done a thousand times......handles like a pig though, the vw box is the one the Hewland type 9 is based on

one idea I have had for a rear engined car is as follows :

What about using a normal live axle, with a smaller bike engine - like a 400 - 500 cc twin - mounted on top of it driving the diff flange via a chain? Sure, the unsprung weight would be a bit high, but what a simple compact one piece assembly.

comments?

atb

steve

Vw boxes are pants, and certainly arent very good at handling 200+ bhp, unless you have them rebuilt at great cost with high strength parts, and always load up the box before letting rip (no sidestepping the clutch etc). You want to drive like a granny waiting for it to explode?
Why not take a renault UN1 transaxle (r25 turbo, most r v6's, espace etc), and mount it in the rear, run a transaxle adaptor to motor of choice, and use granny halfshafts with the commercial half shaft adaptors you can buy.
Strong as a bull, take any motor you fancy, u can use the renault v6 turbo motor with even less hassle, itll handle, and theyre not usually that expensive. Proper mid engined layout without worrys about trans strength.

Ive just ripped out the pinto/vw transaxle from my kitcar and am going this way...

Steve, the bike engine would have all sorts of problems with vibration etc from the axle, being attached to it. Ive ran rigid framed bikes and the frame was prone to cracking from road vibes to say the least. Plus youve got your unsprung weight issues too.
Why not open up the diff, replace the crownwheel with a sprocket and mount the engine just in front of the axle but on the car chassis, with a spring tensioner to keep the chain on when the axle moves up and down and relative to the motor?
The diff should be so lightly loaded (in a ultra lightweight car) that it will survive not full of hypoid. Ive seen this arrangement in a few trikes, and a chain drive is a very efficient way to transmit the power...

you could follow the pattern of the very first cars: they all used chain-drive systems.

I didn't know beetle trannies were so fragile, you could probabaly use one out of an old microbus, with the 2L engine, or maybe a Porsche trans......hehe