So after all basic maintenance and tr6 iridium plugs, CAI with heat shield, 180tstat and new gaskets and o rings I scanned the 2003 PAU. Having only .5* KR at WOT I went ahead and dropped the pulley to a 3.5. Scanned again and got 5* at WOT and maybe half or less of that on the highway at high throttle. I'm ready to order a downpipe now if need be, but i was curious how much knock can be taken out with a good dyno tune. I'm trying to be done spending extra money on this car, what route should I take? Can I go ahead and tune now, or should I opt for exhaust? A bonneville downpipe with cat is $200 and the speed daddy's are right there with it. With the SD I would need a cat, but I could live with that. I don't plan on rockers or cam or IC or any of that. Please let me know what y'all think. Thanks.