Sorry for double post, but Hmmmmm, there are a few (archive)

It's the limited production years of the M20 engine that haven't really lended them to a great amount of upgrades. Here are some I've tried and my opinions (Parts pricing ,my DYI labor in hours):

THE BEST (Suspension first)
Plus 1 or 2 tire/wheel upgrade:
Plenty of used BMW origional or aftermarket wheels for sale. Mine - E31 forged turbines, with Toyo FZ4 tires. Great upgrade, 16" wheels, with 225(front)/245(rear) tires. Interstate ride remained the same, but definate difference in turns and twisties.($600 wheels, refinished them myself, $550 tires, mounted at a tire dealer)
Sach's Suspension:
Mine is on order. Makes twisters more enjoyable.($750+?, 8-12 hours?)
Sway bars:
After shocks and springs and only if you plan on racing.
Brakes:
When finished with the turbo,see below, there is an 850/540 brake upgrade you can do. I'll do it at the same time as the turbo. ($????)

THE BEST (Engine)
Chip:
Yes, it works. 15 hp. But you'll need to fork out the extra $.30 for higher octane gas. Autothority, Dinan, and of course Mr. Jim Conforti. Autothority and Dinan pass emmissions. Conforti's, though on this board known as the best performer, has been known to fail. ($250, 1 hour) If you modify the engine with other parts, yoiu can get the chip custom programmed for even better performance.
Tansmission chip:
None avaialable.
8MM Wires:
You can really feel a response difference. Especially with a chip. ($200, 1 hour)
Turbo:
Nest year I plan on turbo charging this engine. Korman sells a kit for $5000 (240hp). Trying to figure out how to do it with a 524td manifold and other parts for around $2000 and a months worth of weekend labor......to be continued.......

MODERATE

Exhaust:
OEM is high flowing enough. Mostly make a change if yours is shot. B&B, too loud. Had my B&B removed and OEM put back on it. ($500, not worth it.) I've heard good things about Eisenmann exhaust, both performance and sound.

WORSE:

K&N filter:
No offense to those who use it, but I had a cone on mine and after 2 oil changes; I took it off. It's proven no real horse power gain if used in the engine compartment (hot air is less dense than cold air). According to Jim Conforti (The BMW chip guy), studies prove additional particles enter the engine. More dirt = less engine life.

Remember these are my opinion's based on my research and preferences. Also, you'll need to factor the use of a "Human" dyno meter versus the real thing. The best decision you can make is to research the archives of this site.

Also visit, this link. Started and maintained by a member of this board (Bruno).

Best of luck!

Johnny
89 525ia 125K

Hello,
I would like some info. On modifications that I could do to my engine. I have a 1989 525IA. Thanks

BMW E34.net

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