Okay So the Shop Fixed it this time They put the damn thermostat in backwards (idiots) But now magicaly I have a runnability problem which i didnt have when it went into the shop. When I go above 20mph the engine starts to cut out and if i really get on it it backfires and sputters and wont go above 20 mph. The Shop guy said my carb was gummed up. So I cleaned the carb with no results. This is also odd because when I first take off from a stop it has tons of power and quickly climes to 35mph and then starts to sputter and cough until i Bring the throttle back down to about 35%. Fuel, Spark, or What I dont know.

P.S. 1991 Supra 351W 4bbl Holley with electric ignition.

Thanks again guys for the help.