by KinLoud » Fri Mar 11, 2005 8:00 am
Sometimes with exhaust and/or intake mods the pulses of intake or exhaust can get out of time with the valve timing at certain rpms (different resonant frequencies).
Do you still have the original intake system? If you do, maybe think about putting the intake back to original to see if the problem disappears.
Similar thing with the exhaust - do you have original factory exhaust manifold or aftermarket? If aftermarket try refitting the factory exhaust manifold to see if things improve.
By doing a comparison between factory and aftermarket you might be able to see where the problem is.
NOTE - only change one thing at a time. If there is no change then swap the parts back and change something else.
Hope all this babble helps.
Ken
Hamilton
021 408 863