Midlife Crises
Senior Member
I have not run Thumpers but I have heard them. My first bolt in’s were Detroit Rockers. Same class as the Hot Rods. They all offer nice sound and a little more power when tuned. None of this class cams require the springs you have. If you step up to the 127400 or 127500 you will need to use Comp Cams Phaser limiters or lock the phasers out completely. Also note that the 127500 is the “largest” cam recommended for stock heads. Opening the valves more than 0.550” or so on stock ports does not increase airflow.Any opinion on the Motha Thumpr cams?