Whenever the revs are around 31-3200 there is a vibration and some noise.(occurs at idle and crusing in any gear) The noise is louder inside the vehicle but it is slightly noticable outside also. Motor is stock bottom and head it is boosted at 9 pounds. any info would be greatly appreciated. After the winter is over i'll be building a motor for this car but untill then...

 

where does it sound like its coming from?

 

What is causing this problem?

 

nothing is "causing" the problem. it is just abnormal to feel this vibration. i just got finished checking all of the exhaust connections, spark plugs, and njust about every other metal to metal connection i could think of. seems to be coming from the front of the motor. either valve noise or the downpipe connection. dizzy is tight but there is vib coming from there also. leaning towards the valves and or cam. motor has relatively low mileage around 80k. been boosted for around 5k. no problems power wise. just seems odd. Main reason for going nuts is i want to catch the problem before something wears out that could cause a huge problem.

 

Turbo bearing?

 

the turbo is silky smoothe, i've narrowed it down to the downpipe to turbo connection. i plan to make a different gasket for this connection once the car cools and see if that helps/solves the problem

 

spun rod bearing?