I would recommend the us spec 500 over the 380 euro for two reasons....the extra torque will be helpful on the autocross course. A nice fat flat torque curve is what you want there to get you going after a tight turn. Also the us spec 500 runs on regular which is a lot cheaper to buy. A factory original 500 motor with 120k is barely broken in if it has had decent care. Slap in some new chain guides and go. Any rebuilt motor is only as good as whomever built it and you probably don't know who or what they did to it.

I autocrossed my 84 500sec summer before last. It was nice. Not comptetitive against the newer smaller cars, but we surprised some folks and had a great time.

I used the b(?) setting of low the little gate at the bottom of the shift pattern where you push the lever to the right. It will hold whatever gear you are in until you reach a speed while slowing down that will allow first gear at the redline to operate and then it automatically downshifts for you, this is handy when approaching a turn. You will be pretty busy and not wanting to think about shifting down.

Tom W

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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.