I have a 302/5.0 HO motor with a 4bbl, but otherwise stock. Will dumps add or rob horsepower or torque? I read somewhere that eliminating backpressure causes problems and that I would need to lean out the carb... and I've read that there would be absolutely no problem. Which is it? I'd only uncork them for passes at the dragstrip, and they would probably get placed 12-18" from the end of the headers.