I have run 250 shot (Cheater kits) on my bone stock 440 New Yorkers & Newports in the past & even on my 440 Charger before at times with no issues ever. Never blew any of them up. It sure does wake them up. (no quarter mile times, just street sleepers). Just don't use the recommended jetting for the kits. Each car / kit requires it own unique tune & will take a little adjusting to get the plugs looking good.