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Its been a bit but we have been racing and had to build a new car because of a bad early season wreck. I did add a pan evac thinking any aid in reducing internal pressures would help 2 fold. One in would lower the internal pressures to help in ring seal and second it would help prevent oil leaks which can get us a black flag. One question I have come up with as of late came from working on a hobby stock whick is even more restricted with stock exhaust and heads. When building a cheap motor to replace a claimed engine the owner used a "pro am" cam shaft that he got for free. They were a much more open class motor so the engine is now down 40 hp compared to the previous engine. In an attempt to crutch the cam shaft 1.6 rockers were added to the intake. This caused a instant loss of 15 more horsepower. Switching the 1.6 rocker to the exhaust returned the power but had no gain over the 1.5. I guess I am stumped about this. Of course the cam is unknown so the knowledge gained is limited. But thinking why this happened is it the reduction in intake port velocity? That the exhaust is so restricted that a increase in intake charge actually is casing more exhaust gas than the system could handle causing a contaminated air/fuel charge? Why did the exhaust gain nothing? It confuses me. Should we have tried a 1.3 brake in rocker on each side?
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