[Frank]

My 352 is stock except that at some point in its life I discovered it was bored .030 over. (Pistons stamped with .030 when I had the heads off once.)

I understand that you can gain a higher lift with a different ratio of rockers. I have no plans, interest, or money tearing down the engine to install a performance camshaft. So I'm wondering what the pros and cons are of using the performance rockers of a different ratio. It almost seem too easy. How much more lift could one expect? Seat of the pants difference in performance?

 

[Ronbuell]

No experience here, just some reading and wondering the same thing with a 5.0. This is what I've learned: my stock cam is .444 lift. w/1.6 ratio arms. By going to 1.7, it give about .480 lift... The cobra came with 1.7 ratio arms, but a slightly milder cam than mine, more like yours I'd assume. As long as you don't get coil bind, your good to go.

 

[jakengle]

I don't know of any high ratio rockers for FE engines. The stock, non adjustable ones are 1.73:1 and the adjustable ones are 1.76:1, which isn't enough difference to matter for performance.

 

[tbirdchick]

I understand that you can gain a higher lift with a different ratio of rockers. I have no plans, interest, or money tearing down the engine to install a performance camshaft. So I'm wondering what the pros and cons are of using the performance rockers of a different ratio. It almost seem too easy. How much more lift could one expect? Seat of the pants difference in performance?

Changing rocker arm ratios is an old and effective trick. I used to swap 1.7 rockers for the stock 1.6s on SBCs back in my circle track days to beat a 'spec cam' rule. They do add valve lift without changing the duration of your cam and the extra power is VERY noticable. I never ran into it with the Chevs, but the only problem that I can forsee would be possible pushrod misalignment. Right now I'm playing with a '64 223 Ford 6. Since higher lift cams aren't available for these old dogs, I found longer ratio rockers built back in the '50s. But I've never seen them available for FEs.

Jan

 

[dfree383]

A cam change would probably be less expensive and probably much more productive. as the more modern cam profiles produce alot more power than the old grinds.

 

[v8shadow]

I agree with dfree, a cam profile done right will do you so much more good from what ive read. Im learning the benifits myself as we speak.