Thread: Roller rockers 1.5 intake & 1.6 exhaust

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I have heard that using a 1.5 ratio rocker arm on the intake and an 1.6 ratio rocker arm on the exhaust will improve HP. How effective is this setup and is it worth it. I was thinking of using it on my SB Chevy 327. Currently I have the 1.5 roller rockers on both the intake and exhaust.

Most any production head from an OEM is going to flow less on the exhaust as compared to the intake. Most cam grinders make a few cams that feature a dual pattern (more lift and duration on the exhaust lobe) to help equalize flow. You can do much the same thing with a higher ratio rocker on the exhaust. Just be careful to watch for coil bind, retainer to guide clearance, rocker to stud clearance and valve to piston clearance when doing this.

Is it worth the money involved? I doubt it. A cam change would probably be more cost efficient.

I already have a nice cam in the engine and am looking for ways to get that little extra horsepower out of the engine. If I did change the cam how effective would going to a roller cam and lifters be? The current cam is Comp cam Grind number XE262H-10 . The cam was degreed at 104 degrees intake center. The heads on the engine are cast # 14014416 with intake valves at 1.85 exhaust 1.5 the cc is either 62cc or 58cc I'm not sure which and have no idea how to tell which. The carb is an edlebrock 600cfm. #1406.