When is it safe to run a smaller SC pulley?

[blkthndr]

By Bill Evanoff

This is definitely a "loaded" question. It’s like asking, "when can I have safe sex with this guy/girl I just met"? Just as the bible tells us abstinence is the only truly safe sex possible, I encourage the same for SC owners and their desires to spin their blowers faster. Is this too cautious of an approach? Too conservative? Wimpy? Absolutely, but I’ll stick by this recommendation and only vary from it if one condition is met. That is if the engine has headers with larger collectors and an oversize, free flowing exhaust system. Then, it can be considered safer to run a 5% or 10% overdrive pulley. I’m sure there are owners who have successfully used an overdrive pulley for years with their stock exhausts, but TOO MANY others have met with disaster (a blown head gasket) when running this combination.