Just a little backgroung about the car first, it's a 73 Z28 with a 383 and 700r4 converted to fuel injection(speed denstiy). I am useing a holly stelth ram, 58mm tb, 30lbs injectors, 1991 727 corvette ecm and ED Right custom chip. new cran cams H-IR6 ingition & l-92 coil, comp cams hy roller cam 270dur 230in 230ex with 510 lift in and ex, standard tpi distrubitor with new ign module.

Here is the issue: At cold start up it starts good and idels good, if I hit the gas it will rev all the way to 5800rpm good and go back to a good idel. If I hold the throttle at any rpm stedy it will surge down like 600 rpm then rev back up, it will do this every 15-20 sec.

Once at temp and in closed loop it has all the same issues as in open loop and will act the same , but it will start to surge at idel (1000 to 450) then back up, about every 15-20 sec. When I drive the car the problem gets much worse, it has the surge and a miss. I can take off hard for about 3 sec but then it will surge down and start to miss the rev back up. At cruse speed it has just a slight miss every 30 sec or so, under load it's the worst.

Heres the kicker, after about 10 min of steady driving it smooths out, it still surges and misses but only half as much, at that point it is all most comfortable to drive.

I scaned my ecm it seems to be seeing everything the only thing is my O2 mv. they jump from 80 to 800/ 500 to 600/ 100 to 700, I mean not smooth, big jumps real fast and my O2 cross count never stop counting. It goes from rich to lean evenly.

My blm's are at 110-114 a little rich, and the interger(i think that the name) 127-130.

I have tried several fuel pressure settings from 40 to 58 but 46 with vacume connected seems to be the best.

I think the cam is most of my problem but Ed Right didn't seem to think it was a problem. I am stuck and really need some new input so thanks for all the help I know you guys can give me.

Regards
Cody