Just drove for the first time my newly restored 71 GTX 440-6 this past wekkend. The engine builder told me to put on a few hundred miles on the engine and then he would fine tune the carbs. I immediately noticed an erratic idle (even when fully warmed up). It seems to hover around 1250-1300 RMM, then drops to ~950 RPM and jumps back up to ~1250 again. Also, when cruising at speeds above 50 MPH, I can feel the engine pulsating (for lack of a better term), as though it is momentarily starving for fuel; but when I accelerate, it runs fine until I cruise again, and then starts pulsating again.

Specs on my engine are as follows: 440 stroker (496), Edelbrock RPM heads & 6-bbl manifold, 3 Holley repro carbs, 9.0:1 pistons, Lunati 60303 (.494/.514) cam w/1.6:1 ratio roller rockers, MSD distributor/module, TTI headers w/3" exhaust, stock fuel pump, and repro date coded coil. I don't know what the ignition timing is set at. Also, I don't have the idle solenoid installed.

Any diagnosis would be greatly appreciated.