Denny, I like your drawing just fine but I think you were targeting a different application. I know HOW I would install a relay to do it.... what I'm looking for is whether it's a good thing to do and whether it's legal. I guess I can check with NHRA on that latter part. Intuitively, it seems like it would be a good idea to run the motor/fan/water pump off the battery for a 1/4 mile (save a few HP?) then switch the alternator back in after the traps.