Posted by Wietse on January 23, 2000 at 23:38:03:
I am thinking about doing something crazy with my e12 and am looking for some advice.
I want to build a car cable of running the "1 Lap of America" with success. I was looking at building a 944 Turbo or an e36 M3, but something in me says "BE DIFFERENT", beside I already have a really straight and nice e12 with all the tricks.
I think I have decent combination. I don't plan on winning, just have a great time in a very fast e12.
My e12 is a great base for this because she is a euro car, has never had any rust, has a fresh full tilt suspension, perfect interior, no AC,PW,PL, 3000 lbs dry. Currently I have 235hp but would like 450+hp.
To be safe I would install a roll cage for chassis stiffness and full race suspension and brakes.
I am thinking about building a blower motor. I am a bit torn between doing a turbo using 745i parts or building a super charger engine. I need the groups advice.
BASIC ENGINE:
I would use a 3.5 from a 89 or later car because of all the updates including the big valve head and larger intake. I would extrude hone the intake, have the head polished and ported, install forged pistons (CR 8 to 1), piston squirters, balance and blue print the whole thing, include an oil cooler. I would run Motronics, but see if I can get knock sensing ignition to work with it and convert the airflow flapper box to a MAF system.
Building a TURBO would be easier because I could use parts from a 745i, but after owning a Volvo 850 Turbo, I do not like the turbo lag much. The Volvo is very fast, but very tough to drive smoothly. Maybe it is the small engine (2.3L), high boost, 4 long gears in the transmission, but I don't car for it much. I would run a larger turbo and intercooler and that would just add to the lag. The bonus here is I could control the boost and getting 450 hp should be easily possible. Junk 745i's can be bought for pennies.
Building a SUPERCHARGER would tough because the fabrication, but I am guessing it will be a much easier car to drive. Getting 450hp could be possible, but according the experts I would run the blower really hard. I would still intercool the motor. I have investigated a number of kits and talked to a couple of different companies and they said 450 hp would be stretching it for a 3.5L.
Steve Dinan and company were getting around 405hp out of their e34 535i turbos and he had to offer a warranty, so I am sure there is more than 400hp potential there.
Maybe a dual turbo setup? A number of the late model Toyota Supra are getting 550hp++ from their dual turbo setup, but I question the drivability of these cars and I would have to fabricate a bunch of parts.
Frank Haas how does that Alpina Turbo e12 drive? Is all or nothing from the powerplant?
Any advice would be great.
Wietse