The assembler took my old dashpot and accelerator lingage and put it on my new short block. Whats occurring is that the engine idle screw is set to 575 rpms. Now when the engine is turned on it goes to 800 rpms. When I play with the accelerator rod back and forth the engine will drop back to 575 rpms. What could be wrong is it a weak spring on the dashpot or what. This engine is a fe390 into a thunderbird. Thank you Larry. Ps this didnt occur on the old engine at all.