Ok, so having a few Cavi's setting around one running 2 dead... I pieced my old 95 together, which is in much better shape than my 99. All that was wrong with both was a warped head due to overheating. So, on the cheap I decided to make my 95 a fair bit faster by swapping over its head onto the 99 block as well as the 95 crank because it had been turned .020 on the mains and a polish of .001 or .002 on the rods... so I could re-use perfectly fine race grade bearings. The head has also been shaved before, ported, polished, and the valve springs shimmed up. We also re-used the 95 Camshaft. I had to re-buy the main bearings due to a tang on the opposite side in one main... Once we got parts we had it together. Once everything was swapped over to the new block we got it in the car. It ran with no problem and has been doing so for nearly a year now, but one thing was different after the swap and we haven't figured out what or why its doing it. Mind you it is still running on stock everything ECU and Fuel wise. Only mods not mentioned until now are a header and air filter and intake tube.

What its been doing is bogging down and spitting from 1/2 through full throttle. If I gave it a hair under 1/2 throttle and let it rev out it runs fine, but if I nudge it any further it kind of sounds like its being muffled and doesn't pull as hard but still revs slowly. When it muffles and revs it kicks and spits until I let off of it and sometimes it will pop after as well.

What I need to know is if I have possibly burnt some valves(again.. if so its twice now on this particular head.) or is it fuel related. Also I don't know about what comp. ratio I'm running with the shallower dished pistons but we haven't noticed any knocking on 93 octane!

Some advice is greatly appreciated!