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Discussion Starter #1
to all the performance guys with real experience, what I/E ratios have you found to work best with the twin cams?

ive read alot aiming at a high ratio of 90%, is this true, what other factors have you found may alter this.

currently my twin cam is a 4.375 stroke 3.927 bore, 10.92:1, 1.7:1 rollers, andrews 67g cam, 1.94 intake valve and 1.63 exhaust, both cut to 89% with a 1.75 runner matched to my head with 55mm hpi and boarzilla exhaust making 122.5hp @ 5500 and 131tq @ 3900

i had custom cams made with more aggressive ramps, 255 duration on both intake and exhaust with 50 degrees overlap, im getting a flow bench so i can test my heads if i need to make changes, im currently at an 88% I/E ratio but my end goal is 130hp and 140 tq or damn close to it

the new cams are not much different from my current cams, the main difference is the lift and ramp rates

any advice from experienced veterans is greatly appreciated
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