I built a motor for my GTA and ever since I put it in it seems to have problems...here's what I got...350 .030 over, 10.2:1 pistons with the stock center bolt 64cc heads....464" lift cam, 222/266 duration at .050, 1.5 ratio roller rockers.. stock tuned port injection MAF system...no emmissions anything...flow tech headers...I put a new knock sensor in, new oil pressure sending unit, new distributor, new coil, new 8.5mm plug wires...but the car doesn't seem to idle till it's warm, and when I pull out and get on it, it sputters and doesn't seem to want to rev up correctly...WTF is the problem?? Is it an ignition problem??a possible vacuum problem?? could it be that since I don't have my EGR valve or any emmisions crap hooked up it causes it to run like sheit? SOMEBODY HELP PLEASE!!!

 

Are you running a custom prom?

 

Are you sure about the 266 duration on the exhaust side? If so, you could be bleeding too much unburned gas into the exhaust and the system is leaning it out. Also, what is your timing set at?

Changing the cam and airflow of the heads requires changes to the prom, I have a custom prom and it still runs like it needs a choke on cold days..... Guess I need to burn my own prom......

 

you def. need a new prom

 

prom could be the problem since you are probably running the 22#'s still... 24's would be a good idea. and the flowtechs.... i think the manifolds flow better then thoes things, especially with a 10.2 to 1 cr. Any codes when this happens? If you were running that lean, you would get a code from the 02 sensor, prom or no prom. Is the knock sensor for a 350 or a 305? It could be picking up serious knock and sending the timing back. You have iron or alum heads? Iron could help produce some serious detonation because of its heat retention. Have someone scan your car and see what is going on with the engine. It will pick up knock, see the timing, etc....