Quote:
Originally Posted by M3 Adjuster
Agree with all above , and the classic knock on the S14 engine is where you went, however that's not true of a stock S14, but *very* typical of a Modded S14.... Ask me how I know ?!
Control arms on the E30 M3 were a little bit of a weak point for racing but agree none of the chassis issues that plagued E36,E46 and MINI models for a decade or so.
Of course, the E90 M3 V8 is also proving to be just as "fragile" as the S14 with respect to not making it 100k miles before a rod bearing failure. 
What was the issue on the E46M3 that causes them to extend the warranty on the S54 ?
I searched briefly and found this.
01-02 M3 will automatically got it. For 03 models, it's VIN specific. |
01 and 02 M3's originally came with incorrectly manufactured rod bearings (not to BMW's spec) in 2002 they realized what the issue was, recalled the cars with the bad bearings, and extended the engine warranty to 100,000 miles for 01-03 cars. 03 and later cars all came with correctly manufactured bearings from new.
Beyond that, the S54 has two failure points that can bite you , though you can fix both of them in an afternoon for dirt cheap:
1) cam bolts loosen. This is fixed by installing new ones to the factory torque spec with loctite blue. If the originals never loosened you can reuse them, but they cheap enough that nobody does.
2) vanos oil pump drive tabs sheer. This is caused by too large of holes in the oil pump disk. You can get a redrilled oil pump disk for $150 post core return, which is drilled to S50B32 tollerances, and solve the issue.
Once addressed, they're forever fixed (as in, you're fixing the design fault, not resetting the clock on a wear item). I've done 50+ cars for forum members at this point-- it's a 4-5 hour job once you're done it a couple times. First time you do it, set a day aside for it (you do have to retime the engine when done, so don't want to rush).