Boost drop?
07-08-2006, 03:34 AM
#1
Boost drop? I have a QMP kit with a T-67 and a .96 exhaust housing. Log manifold of course, with the larger 2.5" log and 3" downpipe.
When I had a stock engine, the car would see 13lbs of boost immediately and then it would fall to 10lbs and maybe even as low as 9 possibly. Now, with a built engine I am running more boost, about 15lbs, but it is still dropping down to 11 or 12lbs. I noticed tonight that the log is cracked on the number 8 cylinder primary. Nothing major, maybe an inch and a half. It is in front of the primary so I am confident that it can be welded ON the car. Could this be the problem? I am running a different mechanical boost gauge and a different sized wastegate spring so we can pretty much rule those out. Could it be the wastegate itself?
When I had a stock engine, the car would see 13lbs of boost immediately and then it would fall to 10lbs and maybe even as low as 9 possibly. Now, with a built engine I am running more boost, about 15lbs, but it is still dropping down to 11 or 12lbs. I noticed tonight that the log is cracked on the number 8 cylinder primary. Nothing major, maybe an inch and a half. It is in front of the primary so I am confident that it can be welded ON the car. Could this be the problem? I am running a different mechanical boost gauge and a different sized wastegate spring so we can pretty much rule those out. Could it be the wastegate itself?
