well i'm going throught he same thing.
Try some "guranteed to pass" from the auto store.
It's by the octane booster.
Put timing on 8*
Get the car REALLY hot. the hotter the better.
Use premium also.
That should do it.
Did you do any tune-up??? new plug wires and cap/rotor?
You want to burn as clean as possible.
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4.10's,long tubes & 75 shot...Goes 12.50's
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