I have an 88DX with a Z6 swap. I had my head Ported by a local shop and after I put it on it felt slower. The head has been milled about .015" w/Stock cam My mods are ebay header,2.25" exhaust , Short ram intake, Ign timing is stock at 16*. My best 1/8 is 10.2 at 72mph w/ 2.5 60' I seems sluggish till about 5500 where it seemed to pick up. Before the P&P it seemed to have more power thruout the entire power band.