not really affecting my build plans for my slant 6. however, i am not in a big hurry anymore to change out my highway gears. my plans are to change over to the super six 2 bbl, and free up the exhaust , then later on i want to get into the head work to boost compression and get it flowing better. would also like to add a new cam, timing chain,and windage tray at that time. might swap to an electric fan or try to find a clutch style fan.who knows, i might even get better mileage when its all said and done.