rumblefish360 said

I’d say that is a really good combo you have there.
Adding rocker ratio does a few positive things.
A small narrowing of the LSA
Quicker lifting valves which is great for the intake charge. Quicker is always better on street cams.
Adds minor duration. The general consensus is 2*’s.
The added lift to .580/.577 is probably lifting the valve up into a higher and more favorable flow rate. IMO, I have often stated, while not needed, why not lift the valve as high as the heads flow well? It’s grabbing all the head has to offer in terms of flow which equals power.

Staggering rocker ratios can help. This is mainly a try it out and see and the dyno is a quick place to get that answer but less fun, though much more accurate over the drag strip. The power you’ll find will probably be small in terms of “The Seat of the Pants” feel, but might, just maybe, be a nice number on the report.

Overall, the cam is the one thing I’d change. But, everyone here will have their own cam to state is a great cam. The thing with camshafts is, ask 10 people there idea of a “BEST CAM” and you’ll get 10 different answers from idiots to pros.

One can argue that adding rocker ratio is introducing possible but easily (kind of, skill level dependent) avoidable problems with rocker geometry and wearing out valve springs. Ignore this and take the time to look if you need an upgraded spring and take the time to get the rockers where they need to be placed along with the right length pushrod. All of those problems go away when you do it right.

For help on rocker geometry, contact member B3, his name is Mike. He is a geometry freak and loves getting this stuff right.
(Not my word, his. He loves this stuff!)
He is also a really really cool guy.
I have used his services before and will again.

@B3RE

Run what ya got and enjoy. It’ll be good!

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Garrett Ellison said

You say you have ported heads, do you have a flow sheet with them? There are several members here who port heads that open the valves beyond the max lift the heads flow to keep the valve open longer at peak flow. Once on the way open, and once on the way back closed. If the port isn't just all to crap turbulent at the new fully open point of .588/.577 (and the average porting job on a set of Edelbrocks should flow pretty well up to the .600 mark, maybe even beyond...) it should be of some improvement. Rob is dead on, the quicker that you get the valves off the seat to .200 lift and beyond, the snappier it's going to be. I think higher ratio would work pretty well with the big Comp XE/XHR cam, especially if you spray it, but I'm pretty sure that cam calls for more cylinder pressure than what you'd have with it installed on the recommended intake centerline. As far as staggering the rocker ratios, it's pretty common to run less exhaust ratio in the world of SBC's with a lot of claims made that most SBC's see zero improvement on the dyno with higher exhaust ratios dependent on the majority of cylinder heads, so it's mostly left at 1.5 to improve piston to exhaust valve clearance while running higher intake ratios (according to IIRC Joe Sherman and maybe Steve Brul'e, anyway). I've not come across any LA Chrysler testing, but I imagine @Rat Bastid and @PRH would probably have some hands on knowledge in the field.

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