Posted by Craig in Davis on October 22, 2004 at 07:01:24 from 169.237.19.41
I saw the ad for the "high compression" piano top pistons for 3.0L, made me wonder what type of pistons are stock on 528i as my car has "piano top" pistons. I assume they are stock not high compression models. However, when I checked the compression it was 155 to 165 not the 142 indicated in the repair manual. Also, there is no carbon build up on the cylinder/head with 155 psi as it was the one where the headgasket was leaking and it was steamed very clean. So carbon buildup is not the cause of the increased compression if it is indeed increased.
Just curious,
Craig