I went with all 4 long, wanted the power in the mid range, one of the magazines did a whole test about velocity stacks on a R1, and what they came up with was between 4-7hp(change map) by putting on velocity stacks all long. They got midrange punch which is what they wanted, as far as top end at 150mph can you tell if you have lost any upper HP. I have been over 150mph and did not feel a lost of power. What I feel is between 2nd and 4th has more snap. I think for drag racing you would want all short since your want the most HP up high.