well my car is still missing above 4500 rpm's. i changed the TFI module on the dist. set the TPS, i am sure my fuel pump is fine because the car hold fuel pressure even when its missing. if it was bad i would think you'd see a flucuation on the guage. there are no vacuum leaks, the volts dont drop. i am kinda stuck. the car runs perfect until its brought up above 4500 rpms mostly under WOT. could weak valve springs be causing this? i have a set of gt-40p heads ready to go on but i want to figure out the problem first. any ideas? thanks guys