Steve not sure I agree totally the increased ratio adds duration on opening as well as closing. Comp has a nice graph of this.
On my 455 in my 78 right now it is a HFT so the lash goes away as a debate factor but UD 296/312 we picked up HP with each bump of ratio from 1.5 -1.65(1.7 actual) and 1.8. We did not make a pull with the 1.33 break in rockers.
My 470" 409 single pattern SR no difference on dyno between 1.7 and 1.8 rockers
Since lash changes alone can make differences on the same ratio-we found that out on my IA 2 with the same ratio shaft system SR. I think that would be a hard A to B comparison to actually see on the dyno comparison. Tightened exhaust and loosened intake made the best HP and a lobe designed for higher ratio rockers.
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Skip Fix
1978 Trans Am original owner 10.99 @ 124 pump gas 455 E heads, NO Bird ever!
1981 Black SE Trans Am stockish 6X 400ci, turbo 301 on a stand
1965 GTO 4 barrel 3 speed project
2004 GTO Pulse Red stock motor computer tune 13.43@103.4
1964 Impala SS 409/470ci 600 HP stroker project
1979 Camaro IAII Edelbrock head 500" 695 HP 10.33@132 3595lbs
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