Test VariablesAs you've seen, three of the four heads in our test are very close in overall power. One variable that affects any test like this is cam timing. In this case, we chose a dual-pattern camshaft that offers 8 degrees more exhaust duration compared to the intake side. This probably helped the Brodix and Edelbrock heads that had less favorable exhaust flow numbers while perhaps hurting the Dart and TFS heads slightly. The Dart and TFS heads both have raised exhaust ports and strong exhaust flow numbers that likely would have responded with more power by using a single-pattern camshaft. We really can't say that with certainty unless we test this idea, but we have seen results like that with other engines offering high-flow exhaust ports. This is the problem with choosing one camshaft profile for testing multiple cylinder heads. It's entirely possible that the Dart and TFS heads would have produced much stronger peak torque and horsepower numbers had we chosen a single-pattern camshaft. Now you can see why the results of this kind of testing cannot be considered chiseled in stone unless a whole battery of cams go with it. This just gives you something more to think about. Testing all these heads demanded serious planning since each head required its own specific set of Comp valvesprings and retainers, custom-length pushrods, and ARP head bolts.Testing all these heads demanded serious planning since each head required its own specifi Besides burning dozens of gallons of pump gas supplied by Rockett, we also used up a fair amount of gaskets, what with Fel-Pro's oval intake gaskets, the head gaskets, and those slick blue silicone valve-cover gaskets.Besides burning dozens of gallons of pump gas supplied by Rockett, we also used up a fair We spent a ton of time ensuring that all the pushrod lengths were set correctly to verify proper valvetrain geometry for the Comp Cams roller rockers. These are the Brodix heads, and you can see how the valve-cover rail is rather low.We spent a ton of time ensuring that all the pushrod lengths were set correctly to verify PARTS LIST DESCRIPTION PN SOURCE PRICE Edelbrock Perf. RPM-O 60479 Summit Racing $1,779.00 Dart Pro-1 oval, assm. 19000112 Summit Racing 2,483.90 TFS aluminum oval 41300002 Summit Racing 2,095.95 Brodix Race-Rite, assm. 2061001 Summit Racing 2,133.90* Comp hyd. roller cam 35-518-8 Summit Racing 259.95 Comp hyd. roller lifters 887-16 Summit Racing 509.95 Comp rocker arms, 1.7:1 1120-16 Summit Racing 457.39 Comp valvespring, 1.550 933-16 Summit Racing 150.99 Comp titanium ret., 1.550 732-16 Summit Racing 299.95 Comp light steel ret, 1.550 1732-16 Summit Racing 162.69 « | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | » | View Full Article By Jeff Smith Enjoyed this Post? Subscribe to our RSS Feed, or use your favorite social media to recommend us to friends and colleagues!
