rocker ratio

Does anyone use the 1.8 ratio on the exhaust and the 17.3 on the intake anymore.I have read about it but havent heard much on the results?

bigblockpaul wrote:Does anyone use the 1.8 ratio on the exhaust and the 17.3 on the intake anymore.I have read about it but havent heard much on the results?

You can play with rocker arm ratios on a dyno (for example) and thereby alter valve timing events to see what the engine likes. If you find that a 1.73I/1.80E rocker arm arrangement makes better power than other I/E rocker arm combos, then there's nothing necessariily wrong with running that setup as opposed to making a cam change that would result in the same timing events as the rocker arm arrangement that gets you there.

Paul

bigblockpaul wrote:Does anyone use the 1.8 ratio on the exhaust and the 17.3 on the intake anymore.I have read about it but havent heard much on the results?

As Paul said, using different ratio rocker arms on the intake OR exhaust side in order improve performance is a normal thing. With a big block Ford, a stud mount rocker, about 1.9/1 is about the max; any more ratio and the pushrod cup in the rocker gets to close to the fulcrum. Over 2/1 rocker ratio is used with many valve trains using shaft mounted rocker arms.