Working on a 98' C5 A4 with a D1SC blower. The car came in with a really bad tune and for a set of LT headers. The car has bad KR at 5000 that I can't seem to get under control. The timing I am down to is not timing that should be causing 6-9 degrees of KR. The AFR's are within check, 11.8-12.0 for boost. For some reason I seem to remember that there are known issues with 98's with respect to false KR.

I just don't see that the KR is real. I am only running 20 degrees at max advance so I just don't believe its real. If its an issue with the 98 black cloud its killing me! The car is still making decent power but the timing reduction is leaving a lot on the table.

Anyone recall this 98 problem?

Thanks

Howard