The flat configuration engine has mounting issues. Where to put the engine mounts on a flat motor? That's why you see them hanging out in front (Subaru) or back (Porsche).

Most cars are designed with frame rails to set the engine between.

Mounting the engine directly to the transaxle is a very effecient way to do a vehicle though.

At the autocross the Subies and Porsches are both very very quick.

I beat most of them though with my stock Miata.

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.