Our friend Johnny drove in from Massachusetts to upgrade from Blue to Purple Belt. Even with catted downpipes, we were able to hit 602 whp and 632 wtq. Notice the big power dropoff above 6,000 rpm. This is a classic sign of weak valve springs on this 89,000 mile engine. We went ahead and reduced Johnny’s rev limiter and shift points for now to help keep things as safe as possible. At some point in the future, we will want to upgrade the valve springs on this car.