Thread: Opinions wanted.

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I'm looking at roller rockers for my build and I have narrowed it down to 3 choices.

They will be in a stock 1.5 ratio.

My budget for rockers is 250.00

I'll be running a dual pattern Comp 12-239-3 cam

#1. Scorpion part # SCP1002BL 214.95

#2. Crane Cams part# 11744-16 239.95

#3. Harland Sharp part # S1002 221.95

I dont think I can go wrong with any of the above listed but I'd like some other opinions.
AND:
HEI Dist. What should I be looking for in a good HEI

Thanks.
JImmy

What is your reason for roller rockers? The stock ones are good to 6000 rpm plus a little.
There may be better ways to spend 250.00 Just my opinion though.

I was between Comp Cams and Harlan Sharpe for my sbf and only went with the Sharpes because I have a set for my 460 and liked the look of them and the feedback I have read. But I think as long as you stay with any name brand you will be ok.

Don

Originally Posted by Bruce lee

What is your reason for roller rockers? The stock ones are good to 6000 rpm plus a little.
There may be better ways to spend 250.00 Just my opinion though.

I have researched every part of my build down to every last bolt and washer and 250.00 for 15-20 HP is a good deal as far as I'm concered.
My 350 build now stands at 387-395hp with 418-426 ftpnd. So yes I think they are worth every penny in HP and lifespan of the parts.

If your going to spend the money for the rollers, why not go with the 1.6?

1.6 will make your cam bigger

Originally Posted by JBoss

I have researched every part of my build down to every last bolt and washer and 250.00 for 15-20 HP is a good deal as far as I'm concered.
My 350 build now stands at 387-395hp with 418-426 ftpnd. So yes I think they are worth every penny in HP and lifespan of the parts.

well ok you do know you may or may not see the 15-20 hp if you valve train has not the proper geometry . roller rocker will not fix this if your not doing a mild lift check . a stock steel stamp shoe rocker arm will go for 100.000 miles roller rockers will not . really never use roller for the 12 hp ? more for hi lift cams and were you get very hi spring lbs thats were you use them and see a gain.if you added the 10to 20 hp every one claims your have 500 hp before you get the pistons in the engine

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.

wow what can i say dave thanks yep there still alot of nos crane stuff still floating around .there trying to get crane up and running hard to say who or what will be comming out of the new place when all is said and done. i hope the same rocker arms they were very good . if all the tooling was sold they may not make them here .i hope they do make them here in the usa

I thought Crane had reopened???

http://www.enginebuildermag.com/Arti..._ss_cycle.aspx

They have a new 2010 catalogue??
http://www.cranecams.com/catalog.php

Is there something else I don't know of???

Originally Posted by Two8tyThree

I thought Crane had reopened???

http://www.enginebuildermag.com/Arti..._ss_cycle.aspx

They have a new 2010 catalogue??
http://www.cranecams.com/catalog.php

Is there something else I don't know of???

I have seen some of that information as well - but is it the same product is my question - and what I mean by that - is it still made to the original standards or has much of the manufacturing been shipped to low salary countries with lower quality standards, i.e. no ISO 9001 or 2 at a minimum. I probably wouldn't be concerned if it was the old Crane Co. but reorganized under a Chapter 11 Bankruptcy. Is a motorcycle parts mfr qualified - not a clue. Until I know a lot more, I will not use a current Crane product - I can't afford potentially catastrophic engine failures.

Has anyone out there dealt with the new Crane Cams?

Please post your what you bought and your impressions.
I am very interested in their quality also.
One of the first cams I ever bought was a Crane Fireball cam for my 396 Nova.
Had bought many products up to the close, would really like to know if they are same on the reopen.

Thanks

Sorry didn't mean to hijack your thread.
Will start a new thread in Lounge area to discuss this.
Sorry again

Your headline says opinions wanted. OK, here are mine....
1. Stamped steel rockers can be all over the board as far as ratio. It might not be unusual to find a 1.5 ratio rocker that actually measured 1.45.
2. It makes sense that friction, and thus oil temperatures, will be reduced with roller bearings instead of a sliding ball/socket arrangement. Further, it makes sense that some additional hp would be unleashed. Reduced friction at the rocker should also be a little easier on the lifter/lobe interface.
3. Roller rockers will not last as long as stamped steel rockers due to being more fragile in their construction.
4. In a day and time when we should be considering less pressure at the lifter/lobe interface of a flat tappet design, you have chosen the worst possible lobe profile, a high energy grind. Doing the math, you will find only 22 degrees difference between seat to seat duration and 0.050" duration on the opening and closing ramps of the grind you have chosen. This is right at the limit of lifter rise per degrees of rotation and seems to me to be the wrong way to go unless you are trying to make max hp in a racing class that is limited to a hydraulic flat tappet cam. While this profile will get the valve open and closed quicker than a less violent grind, it also imparts maximum pressure on the lifter/lobe in a time when extreme pressure lubricants have been eliminated from off-the-shelf motor oils. The only way you could make this worse is to increase the pressure at the lifter/lobe with 1.6 rocker arms. In my opinion, anyone who isn't willing to spend 500 bucks for a retro-fit roller cam hasn't thought all of this through.
5. Here's a list of camshaft install tips and tricks that was compiled from years of experience installing and running flat tappet cams. Paying attention to all these warnings will still not make the installation bulletproof, but your odds will be better than if you didn't pay attention to them.....
http://www.crankshaftcoalition.com/w...ips_and_tricks