I built a 383 stroker with AFR 190 Heads and a custom cam. The cam is ...
at .050 duration 230 intake 242 exhaust
Gross vavle lift is .510 intake .540 exhaust
LSA 113

I've had numerous tunes on the chip and its finally starting to run better but now I have a sputter. It only sputters between 3000 and 4500 RPM. Before and after those RPM's it climbs no problem. Could this be a timing issue? Everything is new accept for the MSD 6AL box and coil. I was going to change the plugs again to see if they were misfiring. A budy of mine suggested moisture in the cap. I haven't had the chance to look into that.

Any suggestions would be great!!

Thanks in advance!
-Ken

 

Hey Ken,
Troubleshooting of most problems like this should be discussed in a generation specific forum. Transfering-

 

If the TPS is good then who did the tune on the chip?

 

yeah if it is good at a higher rpm and lower it wont be something like plugs because it works above and below....

 

Wester's Garage did the tune. They were recommended to me by Ed Wright. We've been sending data back and forth for a while but can't seem to nail it.

I think next summer I might have to make a road trip over to his shop so he can tune it on his dyno.