I put a crate 4.7L Stroker in my 95 ZJ a few years ago and it has never ran right. It vibrates at 3,000 rpm, it runs lean and misses. My plugs are white and i burn up my cat about once a year.
It has 27lb Bosch fuel injectors and a new fuel pump. Fuel pressure is stable at 38psi even at high RPMs. I have listened to the injectors with a stethoscope and they are all opening.
I have checked the Cam Position Sensor and Crank Position Sensors with an oscilloscope. The two signals are strong but they are out of sync by 10 degrees. I know that the distributor is in correctly because if I move it by one tooth in either direction, it won't run. Besides, the distributor has 13 teeth which would be more like 27-28 degrees.
I have confirmed that the flywheel is on correctly by checking that the forth pules of the CKP sensor goes low at cylinder 1 tdc. Beside, it only goes on one way.
i have also confirmed the cam timing is correct by marking the lift duration on the lower pulley and comparing it to my original motor.
I have tried everything I can think of.
Has anyone ever heard of a cam having the Dist. drive gear cut 10* out of sync? I'm grasping at straws..
Last edited by GODZJLA; 07-11-2013 at 08:30 PM..