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re: e30 m3 exhaust cam gear

[email protected] asks:

>I am considering installing a cam gear on my  73,000 mile 
>'88 M3.  I would like to find out from other M3 owners who 
>have made this upgrade whether there is truly a noticeable 
>increase in mid-range power as claimed.

There are three schools of thought on the cam gear timing.  One, retard the
exhaust timing (Dinan school) and mid-range torque goes up, while high revs
hp goes down.  Two advance the timing so that mid range torque drops, but
peak hp goes up (Frank Fahey school). Three, leave it where it is and
everything is (duh?) the same.

I take my car to the BMW CCA driving schools, as well as other clubs, and
have found retarding the exhaust timing works great.  In disclosure, I
haven't tried advancing the timing, but I, and many others, agree that even
on race tracks hp is not king.  Third to driving skills and suspension,
torque is more useful than hp.  If I was doing the Silver State Classic race,
where top speed is the object, than I would go to an advanced cam gear, but
for tracks, torque is moe usefull.

Downsides?  I haven't noticed any.

While I'm describing an ///M5, the cam gear theory is the same for the M3; in
fact it's the same part.  Hope this helps.

Sherman in a '88 ///M5.