It might not be detonation at all. Detonation sounds like someone is smacking your heads with a hammer. Have you checked you timing? See what its set at first. If its not too high (factory is 10) check your fuel pressure. If your pump is giving out the fuel pressure will drop drasticaly when you get into higher RPM's causing you to detonate. Good news is that a new pump is pretty cheap. Good luck
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95GT B303 cam, 1.7 rockers, 65mm TB, milled heads, 355's K&N, BBK Longtubes, Flowmaster cat back, pulleys, msd coil, 9mm wires, Tremec 3550, Pro5.0 shifter,10.5 Motorsport clutch, FMS aluminum driveshaft, weld in subframe connectors