Now, I'm wondering just how much of a performance increase these 1.6:1 rockers will show on a turbo'd engine that making 25 pounds of boost. Such an engine cannot effectively use a long-duration cam (ostensibly, all that boost will just get blown out the exhaust valve opening on the increased overlap,) so, more lift is the only option... but how much difference will it make? I know that there's "duration" and there's "effective duration," which is a different animal. High lift rockers change the "effective duration," but not the actual duration (the valve still opens and closes at the same point it would with stock-ratio rockers.) More effective duration is also called an increase in the "area under the curve."
I guess we'll see... What works well for normally-aspirated engines doesn't always work at all for boosted engines (more spark advance, higher compression ratios, deeper gearing and more cam duration, for instance.)
:wack:
A different animal...
