98 part throttle retard?
98 part throttle retard? Is there a concensus or solution for 98 part throttle knock issues? I ve been playing with my wifes car on and off for awhile and virtually nothing seems to make a diference. Its a gt76(13-15 psi), intercooled, water meth,6.0 heads mls head gasket, th400 car but otherwise stock. I don t have wot issues. It picks up random part throttle knock. I tested with 100 octane and IT DID make a difference. It surprised me, but it did go away somewhat. It is not repeatable. It did cause retard and what seemed like choppiness, so I smoothed the timing table as much as possible, and now nothing can be felt even if it is pulling timing. This pulling timing is ussually off boost or right at the 0 psi threshold and it will pull 1- 7 degrees, ussually 1.5- 2.5 degrees.
Occassionally it will get a retard spike when lifting off the throttle, although it seems I have that mostly gone. Is this real? I would really like to tune it out rather then just make it not appear if its real. Could it be drivetrain noise? I never audibly hear knock. Maybe its time for a knock box with earphones.
oh yea, one of my last tests was adding timing, I added 4-8 degrees in the middle and smoothed it alot, and there is no real difference, wot timing is at 13-14 degrees. As soon as it sees any power its basically at 25 and going down. Hi timing /low timing seem to make no difference.
Occassionally it will get a retard spike when lifting off the throttle, although it seems I have that mostly gone. Is this real? I would really like to tune it out rather then just make it not appear if its real. Could it be drivetrain noise? I never audibly hear knock. Maybe its time for a knock box with earphones.
oh yea, one of my last tests was adding timing, I added 4-8 degrees in the middle and smoothed it alot, and there is no real difference, wot timing is at 13-14 degrees. As soon as it sees any power its basically at 25 and going down. Hi timing /low timing seem to make no difference.
If it's real knock, then it's possible you have a sparkplug overheating or maybe too much oil is coming through the PCV system.
To test these additional possibilities swap to a much colder plug like an Autolite AR472, and put a clear inline fuel filter on your PCV hose between the valve-cover and manifold vacuum.
To test these additional possibilities swap to a much colder plug like an Autolite AR472, and put a clear inline fuel filter on your PCV hose between the valve-cover and manifold vacuum.
