Hi guys. I have a 1969 SS that had a 355 in it. For the last couple of years I have had issues with the idle constantly changing. I would talke it for a ride, and come to a stoplight, and it would either idle fine, be idling faster, or idle very slow and stall out. However, it would never do one of these things constantly. I had the carb rebuilt twice, and installed a new intake with new intake gastkets and the problem persisted.

Fastforward to this spring, In May my 355 let go. It was a total loss. I replaced it with a professionally built 383 stroker. Other then the block, it is completely new from top to bottom, including a new carb and a new fuel pump. It is a late 80's block with a one piece seal. Eagle forged crank, rods, and sealed power forged pistons. Dart Pro 1 Platinum aluminum heads, Edelbrock Performer RPM AIRGAP intake, etc. Unfortunately I am still having the same issue with the idle constantly changing. Do you guys have any ideas?

The car has the original fuel lines still on it. I was thinking maybe there could be a little pinhole in it, and that may be causing it to suck air and change the idle depending on how the car is sitting or something along those lines. Any help would be appreciated. Its really getting aggrivating. I love the sound of the cam when it holds its idle, but that typically doesn't last long.