Quote:
Originally Posted by 320touring
Hey welcome, and congratulations on driving the right sort of car 
looking through your thread so far a few things spring to mind..
1. The Eta diff (2.93) is too long to work correctly with the m40/m42 4cylinder engines- Ideal ratio for them would be about 3.64 if you didnt mind losing some accelleration
2. If you used an m42 out of an early (pre 1996) e36 (92 onward) the gearbox has a 1:1 5th so would work with the 2.93.
3. The ideal setup for a 2.93 diff would be to build a 2.7 stroker m20 engine- Basically use the 525e (eta) bottom end with a 2.0 m20 head. This would give you approx 180BHP, and a torque curve that starts at 1000rpm- and levels off at max torque from 1700-6000rpm. Essentially build a torque monster to pull that diff. Several folk I know of manage 35+ UK MPG with "Spirited" driving using this setup.
4. 13" wheels will not clear standard e30 Discs/calipers on the car. Minimum wheel size is 14". Car came as standard with 195/65/r14 on the 14" bottle top alloys. I'd suggest fitting 195/50/15- gives a smaller rotating mass, better steering feel and cheap tyres 
5. Oil cooler removal on the m20 is simple- just fit the oil filter adapter from a 2.0 m20- It doesnt have the takeoff for the cooler pipes. Cooler itself is a couple of bolts in the front valance and 2x 24mm fittings at the oil filter.
6. if you're doing the rear beam- Please fit Genuine BMW (Lemfroder) bushes. They last better than anything else,a dn its such a pig of a job to do..
7. The e30's biggest issue is its cD of 0.36 compared to the e36's cD of 0.30, so time invested in cleaning up the aero should pay off hansomely- especially if pulsing and gliding at higher speeds
8. I'm happy to source and ship any bits you may need- e.g. m42 engines/2.0 m20 heads/oil filter bits etc, as as far as I can see you dint get either of these cars over there?
keep up the good work though- more folks shourld drive these rather than 3.8v6 FWD trash that seems to be the marketplace norm over in the US!
Neil |
1. / 2. Thanks, I was aware of that. I do have the 3.73 diff, which would be better than the 4.10 that the 4cyl cars come with. Although I am not happy with the medium case diff on a car that only needs a small case, adds weight.
3/5. We have 325e popular here, no oil cooler, although if the block is machined to accept the oil filter, I can probably just use my VW fitting if the thread is the same (I have a lot of water-cooled VW parts). There is a 520i, perhaps the same 2.0 engine you mention.
4. I can almost get 13" wheels them on the rear with no modification, a tiny bit of clearance grinding to the corner of the caliper. I would love 13" bottlecaps on the car. I don't mind modification, I did find a thread with a guy running a special 13" (for racing?), and all he needed to do was grind a little for steering joint clearance. As for brakes, I can have the rotors turned down and move the calipers in, or use smaller calipers. I would probably run a 14" with 175/60, or a 185/50 if I can find them. I think 175/65 is $43 apiece, it is really difficult to cross-shop different tire sizes online.
6. I was planning on Urethane bushings from $66 a pair, I don't want any shimmy back there if I am going drifting. I need a lathe, I could make a dozen rear bushings from urethane for the same cost as one set of pre-made ones.
8. The M42 came in maybe a 1991 only with the 318iS, but being rare and good cars I can't find them for $600 or less like the 325i and 325e. For a couple years there wasn't a 318i at all here.
I don't have any money for a m42 swap, especially not with parts shipped from overseas. If a complete M42 car lands in my lap for $400 - $500 I might consider it. I should spend my money on the Ninja 250 to really save on gas.
I have an Audi 80 2.0 8v motor that would probably work great, I don't have the longitudinal engine mounts or exhaust, but I think I still have the oil pan and oil pickup tube (it was in a VW Rabbit GTi for a while). No Rear drive transmission for it, maybe a Suzuki Samurai RWD transmission? I know the Diesel is the same trans mount points, and there is conversion parts for that.
Alternatively maybe a 4cyl e36 would be a better starting point for ecomodding.
Wondering what the Cd of an e30 with no mirrors is, also if removing the greenhouse and using a teardrop cockpit would be worth the trouble. I would love a pilot only open cockpit with a roll bar.