I have very bad compressions my mechanic just said. What can be the cause of this? I've had a street ported motor for 6 months with apexi intakes, racing beat exhaust and now the apexi gt and a highflow cat. I never pushed it too hard and let it break in. Can the compressoins be a cause of boost creep or spike? My mechanic said there is evident signs of wear but could this be cause from boost creep or spike?
Thanks
-Daniel

 

Did he use a rotary compression tester? What were your numerical results? What vacuum on your boost gauge does the car pull at idle, and what rpm is your idle at?

So you're running intake/high flow cat/cb on stock ecu? you still have stock ic and precat?

 

Im not sure of the numbers but yeah i still have a stock IC and pre cat

 

It seems odd to me that anyone would put a streetported motor in a car and then bolt a stock precat to it. Not that it can't be done, but strangely inefficient.

Definitely make sure the compression test was done properly, and DEMAND the full datasheet. You shouldn't be paying good money for a mechanic to say "it's no good". You should have numbers for each face of each rotor, the cranking rpm, etc.

Dave

 

How many miles on the motor?

How much boost are you getting with those mods?