Turbo lag on 944 turbo S
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Turbo lag on 944 turbo S
I asked an experience 944 turbo S racer to try my car last week on the track. He commented that there was considerably more turbo lag in my car than in two other cars he had raced. The motor was rebuilt by Memphis Motorworks two years ago with maximum legal work done on the head apparently. The exhaust is open with an open (no plates) supertrapp muffler. I don't think the turbo was rebuilt with the motor. The car has approx. 80,000 miles. Any suggestions regarding what might be causing this extra lag? Thanks.
Larry Weinstein
robinlarry@aol.com
Larry Weinstein
robinlarry@aol.com
#2
eh, he might be right, but it will be easier to analyze if you had any dyno charts... off hand i'd say you might have a vaccum leak, but who really knows without looking. can you hear any leaks when you tap the throttle a little while you're standing over the engine?
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Thanks to all for your suggestions...one more question: how do you evaluate the condition of the wastegate? (Someone suggested that as a possible problem.)I do also seem to hear an air leak around the metal pipe on the driver side, around the short large diameter rubber hose. Or maybe the leak is below that area...or is that just the sound of the air entering toward the filter?
#7
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if the pipe behind the wastegate is hot during idle then it is stucked open.
Konstantin
Do you have a cat in your car? if so it may be clogged. A friend of mine had this 1 month ago
Konstantin
Do you have a cat in your car? if so it may be clogged. A friend of mine had this 1 month ago
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#9
A common problem area is a torn diaphram in the stock 951 recirculation ("blow-off") valve. If yours is leaking, you will lose boost pressure, which will effectively slow your spool up. A leaky or stuck wastegate will also cause a similar problem. Test your bov by applying a 10psi vacuum to it, and see if it leaks. Test your wastegate by checking to see if your crossover pipe is hot when your car is idling.
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I think the problem's solved...although I was running the Supertrapp without any baffles or the end plate, I still had the tube and insulation installed. (THIS IS THE long SUPERTRAPP NOT THE END CAP MODEL). I removed those and...MUCH LOUDER running..certainly not streetable...but much faster response above 3500 rpms or so. The sound insulation was blocking the opening apparently making the car sluggish. We'll verify the improvement at MidOhio in June!