(Kind of Long Response, but I've been thinking about this for a while now).
This is a question I had been mulling over myself, so here are my thoughts.
I had an 88 535is that I drove for several years, which is now parked in my parent's back yard getting ready to be parted out. Last August I bought my e34 535. Both 5spds, diamondschwartz. My e28 had stock is suspension and 16inchers (PO did away with the TRXs, thank God), e34 has 18inch z rated wheel tire combo, billies, H&R springs, upgraded bushings, control arms etc... In some ways comparing my cars is apples and oranges, and I've never driven a bone stock e34.
-The e28 is slightly, but noticeably, lighter: Once I replace the heavy comfort seats with e30 manual sport seats the weight difference will be only about 40 pounds, by my calculation. The e34 carries its weight differently though, and generally feels better balanced.
-e34 suspension is more refined, turn in is sharper, most of the understeer has been dialed out, car is more "tossable" if that's something you can really say about a vehicle of its size. A lot of this can be attributed to the 18s etc, and this comparing the stock e28 sport swaybars to the stock e34 units.
-For whatever reason, the gearbox in e28 shifted much more smoothly. Clutch feel & travel was also far superior in e28.
-Engine management refinements in e34 made that version of the M30 slightly freer revving (even with the dual mass fly wheel) and gave it an even flatter torque curve than the e28 variant. Conforti chip in e34 really woke this engine up, and I think same would be true of e28. That said, my e28 was never chipped and I've been on the hunt for an e28 fly wheel for the e34 (Planning on selling the e28 engine/gearbox as a unit, so I can't use that one).
-Seating position and visibility in the e28 (with sports seats) is the best of any car I've ever driven, with the exception of the early 80s 911.
-The slightly newer ABS in the e34 has less discernable pulses than that in the e28. Brake feel is better, easier to modulate and stay out of ABS in the first place.
-A/C in e34 is 75% better than e28, BUT I never spent ANY time chasing electrical/electronic gremlins with the e28. Door locks worked 100% of the time, never worried about LKM or master relay.
-e28 is definitely more rust prone.
-e28 is noisier, all that trim etc, but it never bothered me. In fact, I hate cars that are "too" quiet, like most of the MBs and newer BMWs
Over all, I don't think its so accurate to say that the e28 is to the e34 as the e30 is to the e36. The e28 and e34 are MUCH closer, at least when talking about the 535. I do think a later model e34 540 would be pretty different in several ways.
In my view, the e34 was the last "old school" BMW. Starting with the e36 the cars have, on the whole, gotten much heavier, overly complicated, and bloated. They might be faster, but I don't think they're better or more pleasureable-handling.
Last edited by NY535iManual; 07-06-2006 at 11:48 AM.
1989 325iX 5spd Coupe Koni Adjustable/H&R
1989 535i 5spd Bilstein Sports/H&R, Tri-Flo, Conforti, UUC SSK
"If it isn't Diamondschwartz, it isn't... Dark Grey?"