Got a set of 500-cfm Big Chief heads that flow to over a full inch of lift, but keep eating valvesprings?How about a Pro Stockcaliber motor that keeps bending cam cores like a wet noodle? True cam experts are sometimes harder to find, but fortunately, we’ve tapped into two of the sharpest minds in the industry.
We’ve offered serious cam discussions in the past; however, this month’s How It Works takes it to a whole new level.
Cam tech is indeed a complex science, but the typical hot-button itemslike how duration and lift affect the power curve and how to set valve lashhave been covered in exhausting detail already in dozens upon dozens of past stories.
The goal this time around is to focus on hard-core topics eating away at hard-core racers; if you want to know how to adjust your cam specs to help get your small-tire drag car hook, keep reading.
For circle track racers wanting big power and rpm, but are limited by maximum valve lift rules, you’ll find helpful advice in the following pages.
This effectively alters the shape of the torque curve.
Every time you add duration, whether it’s on the intake or exhaust lobes, you move the torque curve higher up in the powerband.Sometimes, just adding 4-8 degrees of duration on the exhaust lobe and widening the LSA 1-2 degrees will be enough to make a car much easier to hook up at the track.It’s a good problem to have, and it beats not having enough power. A very effective solution is to widen the lobe separation angle.The wider we can pull the LSA apart, the softer we hit the tires.This spreads the powerband out a little bit and moves the torque curve higher up in the rpm range.If that’s not enough, the second step is to add a few more degrees of duration on the intake lobe, exhaust lobe, or both.