Thread: Opinions wanted.

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Pat.

If I added up everything everyone told me i'd have well over 500hp with a little bitty cam and be able to pull a house down with this 9.5CR motor.
The Proper Valve Geometry is something that I'm learning about right now so that I can have everything as close to "Perfect" as one can get.

You may want to look at this option instead,a stainless steel full roller rocker would give you a longer life than aluminum would if you plan to put miles on it.Click on this:www.kmjent.com then put KMJ 0235001 in search,and it is in your budget and has a stout warranty.

First of all, believe what Pat McC says - he is our sites resident super expert, especially with Chebbie engines.

Now - my opinion - why 1.5 ratio rockers? You gain exactly nothing as far as enhanced performance. A wee bit of rolling resistance has disappeared - a couple found horse power, maybe, but you haven't done a thing except install a set of "break in" rocker arms. I used this site to do my calcs for my Ford labeled Crane 1.7's in my SB Ford: http://www.wallaceracing.com/rockercalc.php

My original ratio rocker was a 1.6, the new cam lift was .498. With the 1.7 rockers, my effective lift is now.529. A heluva lot better with .031 more lift - that's 1/32nd of an inch which in camshaft language, a lot more air/fuel in for Hp out

Your camshaft is a pretty mild dual pattern, I'll use the .480 lift first. Doing the calcs, with the 1.6 ratio, you would end up with an effective lift of .512. With the .462 side, the lift would then be .493. Now, that's where you will probably see some Hp gains.

Brands - I don't know who makes Crane now since they went out of business, but I would guess that they are no longer made in the USA. And whatever you buy, make sure they are full roller, not just rollers on the tips/valve stem end.