The reason they run rat motors in Pro Stock is because the motors have to be NA, thus a need for bigger cubic inches to make power and I'm pretty sure they don't run turbo 4 cylinder motors in NHRA Pro Stock last time I checked but I can be wrong. You can make a lot more power with a turbo big block than a 4 cylinder, but trying to hook up all that power is another story...
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1970 Chevrolet C-10 w/355sbc
2010 Silverado Daily Driver
1971 Mercedes 280sl project car