Expert: Josh Fields - 10/31/2006

Question
Hi Josh

I have an e30 325i that I has been recently been stroked to 2.7. It has a gas flowed head and a 288 billet cam. The problem is that I find the cam comes in a bit late compared to an alpina cam. What is the degree on the alpina cam and is it a split duration on the exhaust and inlet or is the same on both sides. I also dont think I have an o2 sensor on my car. How inportant is it and will it affect the power.

Answer
Rishaad,
 I've actually done this same conversion, by using a 524td crankshaft, but I didn't change the camshaft.

 288 is a pretty "racy" camshaft.  I'm not familiar with the Alpina cam, but I can almost garauntee that it's less lift than the 288 you have.  This would explain why your cam comes into power a little later.  One thing you should be very careful with is the rocker arms.  I've been to countless races where guys are running these high-lift cams, and at really high rpm the rocker arms will break.  Half of the racers just run the stock cams to keep this from happening.
 
 The O2 sensor is very important.  Unless you are running a carburettor on this engine, you need an O2 sensor.  It should be about a foot down the exhaust from the manifolds.  Without this, your computer has no idea of how the engine is running (rich or lean) and wont be able to adjust to the correct settings.  Running too lean is bad, as this will burn up your engine, and running too rich is bad as well... it limits power.

 Good luck,
 Josh