Well with out stepping on STOGI's toes too hard hes 1/2 right. I feel it will improve mph only because if you put heavier weights and nothing else. You'll lower the shift engagement rpm & the shift out rpm. So lets say you had a 7000 rpm shift out, and a rev limiter at 8000 rpm stock. If you put heavier weights in it will be 6500 rpm shift out. You still have a 8000 rpm rev limiter. So when its done shifting you 1500 rpm's left to go for top speed, vs 1000 rpm stock. However you have to have the HP to pull it off the line, carry it throwout the shift out, and to the rev limiter! So if the max HP is made at 7000 rpm and its shifting at 6500 rpm. It'll get from point A to B slower. But at point B it'll have more mph then stock. So yes more mph but slower to get there. you'll only see more mph after 7500 rpm in this scenario above.
There are better ways to get more mph and still keep the low and mid range a Dynatek cdi that bumps the rev limiter up and HP, or an overdrive clutch. or both if you want to name a few.
SORRY STOGI I mean no harm but you left out the rpm after shiftout in done.
