Richard Holdener
December 1, 2009

Once we had completed Part 1 of our testing, we were anxious to see what happened once we added boost. In normally aspirated trim, the combination of the RHS heads, XFI cam, and Edelbrock RMP II intake improved the peak power output from 307 hp and 401 lb-ft of torque to 448 hp and 420 lb-ft of torque. That represented peak-to-peak gains of 141 hp and 19 lb-ft of torque, but the gains were as great at 200 hp out past the respective power peaks.

But would these gains remain consistent once we added the Paxton supercharger to the mix? By this we mean would the supercharged modified motor produce another 141 hp more than the supercharged motor with the stock components? Since we were limiting the boost pressure to a street friendly 8 psi, would the stock motor with the blower produce as much power as the modified motor with the blower? And since we didn't plan on performing any pulley swaps, what would happen to the boost pressure between the two combinations? Would the added airflow offered by the modifications reduce the boost pressure compared to the stock components?

These are but a few of the questions we plan to answer in Part 2 of our Fast Ford Formula.

Airflow Data
Stock E7TE Vs RHS 200 CC
As-Cast Aluminum
IN/ExIN/Ex
LIFTE7TERHSGain
0.10055/4072/60+17/+20
0.200110/75154/121+44/+46
0.300142/100208/159+64/+59
0.400160/110254/184+94/+74
0.500157/112271/193+114/+81
0.600153/111274/199+121/+88