I run an eddy rpm intake on the factory head and cam. It's a little big but it picked up .2 in the 1/8th, and .3 in the 1/4. The 1/8th run was all I could muster out of it, but the trip to the 1/4 mile left a tenth or so on the table. It ran a 13.80 with full exhaust, gears, and intake, so it's not too shabby.