Hello Everyone:

I recently had my valve cover gasket replaced due to a leak. After the replacement I am noticing an improvement in perfromance. Is it my imagination or can performance be improved that much by fixing the oil leak?

Michael

 

I dont see why this would cause an increase in performance. Did they do anything else while you were there? ie plugs,air filter,etc? just doing a valve cover gasket shouldnt cause any loss/gain in Hp/Torque.

 

The only other thing that they did was add the M7 strut tower plates. I was a bit surprised as well, but the engine seemed to be pulling stronger. Could the better seal have created more compression?

 

I think that when the intercooler came off to get to the vavle cover, the mechanic probably noticed all the oil in there and drained it and sprayed some throttle body cleaner in there to wash the inside out.

 

Unless something else was done, changing a valve cover will have no effect on engine performance. That area really has nothing to do with compression in the cylinders. Either they fixed/cleaned something, or your butt dyno needs recalibration.
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Well, the area under the valve cover is always kept under a slight vacuum by the emission-control systems, but if you had enough of a vacuum leak through the valve-cover gasket to make a noticeable performance difference, I would have hoped that the OBC system would have thrown a code.

 

No. There were no codes, but I believe that they must have cleaned the oil off of something, at least that is what my butt dyno is telling me.

 

If it feels good, go with it.
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Well, I just can't read, so here's a pretty cool link...

http://www.youtube.com/watch?v=KO0yR4mapSs&eurl=http://forums.bimmerforums.com/forum/showthread.php?t=996711&page=2

 

If you have a MCS, there was a chance that your intercooler boots had loosened, and once the intercooler and boots were replaced and everything tightened up, any leak you might have had and subsequent boost loss would now be fixed. It's a common problem with the supercharged engine, in fact.

 

Replacing the intercooler boots with ones from ultrik solved my apparent boost leak.