[mreid]

What alternator do you have? Is it the same one you used with the old engine? Are these the same fans you used with the old engine? Your new engine has less torque at idle and the current pull on the alternator puts load on it and it can drag the rpms down. With an aggressive cam, it can stall the engine. Working with timing can help, however you don't want performance to suffer to fix this problem. Kind of like substituting one problem for another. A dashpot won't help. They are simply designed to cushion the return of the throttle to the idle screw position and were originally used in automatics were the torque converter doesn't allow the drivetrain to perform the same function. Worst case, you would need a throttle solenoid like those used with a/c. It bumps the idle up when the compressor is puting load on the engine keeping it from stalling. This is the problem you are experiencing only the load is coming from the alternator. Perform the checks listed above before considering this solution, but don't end up substituting one problem for another. Good luck!