BBC rocker arm options

[Jet City]

I'm upgrading to a solid roller cam this winter and would like to upgrade my rocker arms as well. It appears the shaft systems are superior to the stud type, but of coarse more costly. The two shaft systems I'm really looking at are Jesel Sportsman and Yella Terra (T&D is out of my budget), does anyone have experiences good or bad with either of these? If I end up staying with the stud type I was considering Comp pro-mag rockers, ARP studs and Crane gold girdles, if anybody has a pro/con view for shaft vs stud, I would also be intersted in hearing what you have to say. My application is v-drive lake hot-rod that may see 6800 (ish) rpm on occasion.

[Moneypitt]

The shaft rockers are the latest craze among hipo builders. But as you said, considerably more $$. For a "Lake hotrod" the stud type rollers, or for that matter the ol' stock steel stampings are more than enough. The shaft deals are state of the art stuff and all the high reving, high dollar builders are using them. 6800 once in a while doesn't need the extra expense. A good set of girdles, and studs will do the same thing for your application...........MY .02.....MP
PS I can remember when the "new roller rockers" first came out, everyone wanted them, but their relieabilty left something to be desired. The stockers would out last them 4 to 1..........

[steelcomp]

Shaft rockers have been around for a LONG time, and if you can afford them are the only way to go.
The newer individual mount shaft rocker systems (sportsman style) are offered as a budget minded approach to shaft mount rockers, but really don't offer the same advantages as the one piece set ups. Unless you have really high spring pressures, which for your application you don't really need, you can stick with stud mounted rollers. Don't buy cheap...the set up you described would work fime IMO BUT...and this is an important BUT...call Comp Cams and ask if there is a recommended "not to exceed spring pressure" for those rockers. This is important as there is often a limit that they don't disclose in their catalogue or adds. Although guaranteed, and a nice rocker, they are still a "budget" rocker, as compared to their Hi Tech Stainless. With even mild roller spring pressures, a good girdle is a must, along with ARP studs...if you're running the Crane four bar girdle, I'd think about changing to a three bar style that ties the int. rockers and ex. rockers together. The four bar is OK...better than nothing, but the 3 bar or even the one piece (harder to install) is definately better.
Stock rockers are the FIRST thing that should get thrown away, and are definately not "more than enough". If you tried to run a stock steel rocker on your solid roller cam, you'd have some serious valve train damage...if you could even turn your motor over. Minimum you'd have to change to long slot rockers, and that might not allow for your lift. Plus with roller springs, those rockers would flex like crazy, and they're really inconsistant as far as ratio goes. They have way too much friction, and would probably burn up at the ball pivot, as well.

[Jet City]

Thanks for the input guys, it sounds like a good stud system is the way to go for my application and budget. In regard to the comments about the 4 bar girdle, I was just reading about a 2 bar girdle that looks really ridgid, Webster Industries makes it (GoFastRacer had very positive comments in a previous gearhead post), this looks to be a really nice girdle.
SC, your comments about the pro-mag rockers make me leary, I know it may sound like I'm trying to split hairs, but I will have quite a bit invested into this solid roller project, just want to make the best choices I can and not have any problems, are there any rockers that would be prefered over the pro-mags? Nobody seems to be having any troubles with the Crane gold rockers, how about Scorpion?

[steelcomp]

Thanks for the input guys, it sounds like a good stud system is the way to go for my application and budget. In regard to the comments about the 4 bar girdle, I was just reading about a 2 bar girdle that looks really ridgid, Webster Industries makes it (GoFastRacer had very positive comments in a previous gearhead post), this looks to be a really nice girdle.
SC, your comments about the pro-mag rockers make me leary, I know it may sound like I'm trying to split hairs, but I will have quite a bit invested into this solid roller project, just want to make the best choices I can and not have any problems, are there any rockers that would be prefered over the pro-mags? Nobody seems to be having any troubles with the Crane gold rockers, how about Scorpion?
I'm not sayiong there's anything wrong with the Comp Pro Mags...just check them out. They might be totally fine. No splitting hairs, here. You're doing the right thing. The hours you spend finding out this info will be invaluable. This is how we learn this stuff, and it's OK to learn from other's mistakes. No sense in re designing the wheel.
I'm in the same boat you're in...the last thing I need to buy for my 496 is valve train. It'll be 820-840hp n/a, and although I haven't had any problems with them, I'm hesitant to get aluminum rockers. The Crane golds are sort of the "standard", and there is the "wide body". Lunati makes a great alum rocker, and I think The Comp rocker is ok. The Comp Hi Tech stainless is indestructable and rebuildable (as is the ProMagnum) and so is the Crower stainles. These are used more for endurance, but in your app I would consider them. I think I'm going to go with the shaft rockers, but I'm still in the parts buying stage, and in no hurry. If you want an aluminum rocker that's expensive, but really the chit, look up millerrockers.com. Jim Miller makes some of the finest aluminum valve train available. I think I'm going to use his shaft system.
I wouldn't go with Scorpions, or any of the other off shore brands. You will get what you pay for.
The only other possibility for aluminum, if they still make them, is Isky. They used to (may still) make this huge blue endurance aluminum rocker. I think Edelbrock made a similar one in red, too.
As far as girdles go, I look for the fact that they tie ALL the rockers together, and then ease of use. There's a lot of nice hardware out there for that app. These guys on the boards like Fiat, Go Fast, and others who are racers have better input on that than I do as far as user friendly set ups. They'll tell you.
Hope you're not totally confused, now.
steel

[Jet City]

SC, I think I'm far less confused now than when I started this thread thats for sure. I'm in no burning hurry to round up these parts as I have all winter, but I do enjoy the learning process (and the wrenching). The Scorpions are made in USA, I keep seeing some very credible builders using the Scorpions on their crate engines, here's a 1000hp Pfaff crate that comes with Scorpions http://www.pfaffengines.com/1000sc.shtml , they seem very nice from what I see and read.
At any rate, I think I'm getting the picture that most of the good qaulity, name brand $200-300 rockers have proven themselves reliable in applications far beyond the scope of anything I plan to build. I guess the thought of anything leeding to a roller cam/lifter failure got me a little bit nervous.
Scott

[steelcomp]

SC, I think I'm far less confused now than when I started this thread thats for sure. I'm in no burning hurry to round up these parts as I have all winter, but I do enjoy the learning process (and the wrenching). The Scorpions are made in USA, I keep seeing some very credible builders using the Scorpions on their crate engines, here's a 1000hp Pfaff crate that comes with Scorpions http://www.pfaffengines.com/1000sc.shtml , they seem very nice from what I see and read.
At any rate, I think I'm getting the picture that most of the good qaulity, name brand $200-300 rockers have proven themselves reliable in applications far beyond the scope of anything I plan to build. I guess the thought of anything leeding to a roller cam/lifter failure got me a little bit nervous.
Scott
There ya go!! I stand corrected on the Scorpions. :D
Look up www.millerrockers.com anyway. There's a ton of pages there that you can learn from regarding rocker geometry. I've been in this business a long time, and even some of the best engine builders still don't get the idea of correct geometry. The info on Jim MIller's site is really good info, and written very well. You'll like it.
Good luck.

[Jet City]

Its interseting you bring up the Millers, these must be them? I'll check out their site, thanks for the link.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7933083724&category=33624&sspagename=WDVW

[steelcomp]

Its interseting you bring up the Millers, these must be them? I'll check out their site, thanks for the link.
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7933083724&category=33624&sspagename=WDVW
Yes, those are them, but an older style. You can get them from Comp Products for $199.00. I asked Jim Miller about them and why so cheap (for his rockers) and he said they were a close out design that were being sold in lots to certain buyers. The newer design is an improvement, and he said a better rocker. I doubt there's anything wrong with these...it was about a year ago I talked to him and don't remember exactly what he said. Definately check out his web site.

[Moose]

Nobody seems to be having any troubles with the Crane gold rockers, how about Scorpion?
I ran the Crane golds in my 489 BBC and had one of the cups that hold the needle bearings in, break and filled the motor with all those little bearings :angry2: . I checked the other rockers and found three more that were very lose. I sent them back to Crane and they sent me new ones that I sold and bought Comp rollers and no problems yet :cool: .
Moose

[Jet City]

Don't buy cheap...the set up you described would work fime IMO BUT...and this is an important BUT...call Comp Cams and ask if there is a recommended "not to exceed spring pressure" for those rockers. This is important as there is often a limit that they don't disclose in their catalogue or adds. Although guaranteed, and a nice rocker, they are still a "budget" rocker, as compared to their Hi Tech Stainless.
Steelcomp- Thanks for the heads up on this, I called Comp this morning about your above statement, the tech I spoke with claimed there was no particular limits on spring pressure, but he said they don't recomend using the Pro-Mags above .650 lift (he didn't say why), and recomended that I step up to the SS Hi-Tech series for my application. I'm a little dissapointed Comp didn't make this known in any of their adds for this product, on the website or otherwise.
Even though I've read of two guys reporting problems with them, I found a deal on Mad Dog Racing for the Crane Golds that may be too good to pass up. Now maybe I can start zero-ing in on my cam selection!
Thanks to all for the input-

[steelcomp]

:D :D Did you ever check out the Miller rocker web site?? I think this is a must read for anyone building their own engine who want's a deeper understanding about valve train and rocker arm geometry.
Steelcomp- Thanks for the heads up on this, I called Comp this morning about your above statement, the tech I spoke with claimed there was no particular limits on spring pressure, but he said they don't recomend using the Pro-Mags above .650 lift (he didn't say why), and recomended that I step up to the SS Hi-Tech series for my application. I'm a little dissapointed Comp didn't make this known in any of their adds for this product, on the website or otherwise.
Even though I've read of two guys reporting problems with them, I found a deal on Mad Dog Racing for the Crane Golds that may be too good to pass up. Now maybe I can start zero-ing in on my cam selection!
Thanks to all for the input-

[Snowboat]

The address of the link won't open. Are you sure its spelled correctly?

[Infomaniac]

Here You Go (http://mid-lift.com)
Lots of good stuff there.
I prefer the Comp Pro Magnum rockers.

[469 the coyote]

I used to work at Ron Grose Racing, and we built alot of big power motors. We used comp alum rocker a webster girdles and arp studs. the cranes, crower and scorpian are also good. The same company makes the comps, cranes and scorpian rockers in florida. The companys will not tell you that but I have been there and seen them made. Just my 2 cents hope it helps.
Lester

[steelcomp]

The address of the link won't open. Are you sure its spelled correctly?
www.millerrockers.com this is not a hyperlink...you'll have to type it in your self. :coffeycup
oops...I guess it is a hyperlink.
there ya go.
OK...checked it myself...don't know why it's not opening. Sorry...it's the right address unless they've changed something. I'll find it.

[steelcomp]

I used to work at Ron Grose Racing, and we built alot of big power motors. We used comp alum rocker a webster girdles and arp studs. the cranes, crower and scorpian are also good. The same company makes the comps, cranes and scorpian rockers in florida. The companys will not tell you that but I have been there and seen them made. Just my 2 cents hope it helps.
Lester
They're made by the same company, but definately not to the same specs, or out of the same material...
Crane Golds are available from Comp Products as an engine builder's special...non anodised for $192.95 a set...same rocker without the cosmetics.
I looked into the Scorpion...good rocker. Built for 800+ lbs spring pressure, .800+ lift...guaranteed for life to original purchaser. $194.95

[Jet City]

Steelcomp, yes, as a matter of fact I did check out Jim Millers site, HOURS of reading, I plan to bone up before this whole mess goes together, thanks for the link.
496, thats interesting you mention that, Scorpion has another line of rockers on their website that are obviosly extruded from the same die that the Crane Golds are pushed out of, and yes as a matter of fact they are located in Florida, contact info is just some legal folks, they are evidently a large subcontractor that offers many mfg. processes including ano and variety of platings. I suspect that Scorpion is a house brand name for that subcontractor.
Here is Scorpions webpage
http://scorpionperformance.com/services.html

[steelcomp]

Steelcomp, yes, as a matter of fact I did check out Jim Millers site, HOURS of reading, I plan to bone up before this whole mess goes together, thanks for the link.
496, thats interesting you mention that, Scorpion has another line of rockers on their website that are obviosly extruded from the same die that the Crane Golds are pushed out of, and yes as a matter of fact they are located in Florida, contact info is just some legal folks, they are evidently a large subcontractor that offers many mfg. processes including ano and variety of platings. I suspect that Scorpion is a house brand name for that subcontractor.
Scorpion Performance Products
Custom Design Performance, Columbia, CT.
Auto machine shop, high performance parts, and accesories

[Infomaniac]

Here You Go (http://mid-lift.com)
Lots of good stuff there.
I prefer the Comp Pro Magnum rockers.
This is the Miller link

[steelcomp]

This is the Miller link
cool...thanks. He changed his URL to mid-lift.com. :D
Info...you're pretty sharp, do you have any input about the Miller stuff?

[PC Rat]

The newer individual mount shaft rocker systems (sportsman style) are offered as a budget minded approach to shaft mount rockers, but really don't offer the same advantages as the one piece set ups.
What advantages are they lacking?
If I was building another engine I think I would go with something like the Sportsmans. The price of some good stud rockers, studs, guide plates, and girdles is pretty close to the price of the Sportsmans.

[steelcomp]

What advantages are they lacking?
If I was building another engine I think I would go with something like the Sportsmans. The price of some good stud rockers, studs, guide plates, and girdles is pretty close to the price of the Sportsmans.
The whole idea of shaft rockers is rigidity. Where you have a one piece rocker stand tying all the rockers together, you have a good design since the rockers really can't move independantly. With the individual stand shaft rockers, they can move independantly, and aren't tied to eachother. IMO, a stud girdle and stud set up is better for controlling valve train movement, since it at least ties everything to gether.

[Fiat48]

A set of Miller rockers just arrived. Now...who has that high dollar tool that he claims is the best way to check geometry?

[steelcomp]

A set of Miller rockers just arrived. Now...who has that high dollar tool that he claims is the best way to check geometry?
Hey, who'd you get the Millers from? Are they the latest version? Comp Products was selling the gold ones, but Jim Miller said those were a discontinued version, and Comp Prod. was getting them cheap! They're the chit for a stud mount roller rocker. Even the old ones.

[Fiat48]

Comp products $199.00. Rocker looks good to me.

[steelcomp]

Comp products $199.00. Rocker looks good to me.
Nothing wrong with those at all. Top shelf stuff. Killer price.
If you go into his website, he explains how his little tool works, and why. The guy is way technical, but definately knows his stuff. :coffeycup

[Fiat48]

O.k. I have read all (some) of Millers stuff as to rocker geometry. I have the old Lunati method writen down in some old notes.
I've got a long valve motor out here and I'm a little suspect of the rocker studs locations. On this particular motor, the Lunati checking tool (which I have) and the Manley checking tool do not agree on pushrod length required. And centering the roller wear pattern in the center of the valve stem requires a different length than the Lunati or the Manley checking tools want. So for the Hell of it, I am going to 4 methods of checking with the Millers and see what I come up with.
Methods:
Lunati Old method (should be same as Miller's..he claims he wrote it).
Manley checking tool.
Lunati checking tool.
Determining the length by best center wear pattern on stem.
And finally Millers method. By measuring his way. Not going to buy $130 tool.
About a week...I'll let you know the different pushrod lengths called for by each method.

[steelcomp]

How much longer than stock are your valves? There becomes a point when using real long valves where standard rocker dimensions are off the chart. Using extra long valves move the valve tip closer to the stud, which can require a rocker with a shorter distance between thew fulcrum C/L and the roller tip C/L. Miller adresses this in his website somewhere. Remember...the center of the roller tip will NOT be in the middle of the valve at mid lift, even with correct geometry. You may never get the roller to run in the middle of the valve if the valves are that long. Your pattern will be pushed to the front side of the valve (ex. side) since effectively your rockers are now too long. Hope that helps.

[MikeF]

A set of Miller rockers just arrived. Now...who has that high dollar tool that he claims is the best way to check geometry?
Just "square up" the top line on the rocker w/ the stud base, or 90 degrees from the stud shaft.........at midlift. Using an adj pushrod.
Believe I got that right. :boxed:

[Fiat48]

Steelcomp: Valve is only .100 long. That's why the mystery. I've done .300 long and had the Manley and Lunati checkers agree pretty close.
Mike: Yeah..that makes sense. Will chase all methods and see what we come up with.

[PC Rat]

The other day I was reading an article on the new small block 427 engine for the Corvette. I believe it said the rocker arm ratio was 1.8. It makes me wonder if they have found an advantage to using a larger ratio rocker arm, rather than putting more lift and duration in the cam. Maybe from moving the lifter and pushrod less with a smaller cam.
Brian

[steelcomp]

Steelcomp: Valve is only .100 long. That's why the mystery. I've done .300 long and had the Manley and Lunati checkers agree pretty close.
Mike: Yeah..that makes sense. Will chase all methods and see what we come up with.
That shouldn't be a problem. What's the mystery? Are you having geometry trouble? Mike's almost right...you want the rocker at 90* to the valve, not the stud, at mid lift. By 90*, that means an imaginary like through the c/l of the trunion, and the c/l of the roller tip. Miller's tool takes into consideration the diference between the angle of the valve and the rocker stud, so it can be used on the stud, but it's not at a right angle. (The stud actually bisects the angle between the valve and pushrod) Use a spring height mic or snap guage to set your valve ht. This is an area where very small amounts can equal many degrees of crank rotation. Don't worry about where the rocker tip is on the valve, unless it's REALLY bad. The tip, if things are correct, will be slightly forward of center on the valve (toward the exhaust side) at mid lift, but it's going to be where it's going to be. The critical part is that line through the rocker c/l's is at a right angle to the valve at mid lift. Otherwise you have wasted rocker motion either before or after mid lift. Remember, you're trying to convert a radial motion into a linear motion. Pushrod too long, you go over center with the rocker, pushrod too short, you go under ctr. Either way you will lose trtanslated lift to the valve, and cost crank degrees of rotation doing so.

[Fiat48]

"Don't worry about where the rocker tip is on the valve, unless it's REALLY bad"
Using the Manley checker and an adjustable pushrod...when adjusted to "proper" length....the rocker is nearly off the valve tip. Never seen that before.
Using the Lunati checker and an adjustable pushrod....the Lunati wants a lot longer pushrod....but even that seems to be short. Roller tip on rocker at closed position is still nearly off the valve tip.
Using "best pattern for center of valve tip" method...pushrod would be a lot longer...but pattern still too wide and again...short of the middle.
And I have used this particular camshaft grind with this particular base circle many times before.
Somethings up. That's the mystery. But I will find it. Just going to use all methods and see what pushrod lengths are called for. Perfect Guinea pig.

[steelcomp]

"Don't worry about where the rocker tip is on the valve, unless it's REALLY bad"
Using the Manley checker and an adjustable pushrod...when adjusted to "proper" length....the rocker is nearly off the valve tip. Never seen that before.
Using the Lunati checker and an adjustable pushrod....the Lunati wants a lot longer pushrod....but even that seems to be short. Roller tip on rocker at closed position is still nearly off the valve tip.
Using "best pattern for center of valve tip" method...pushrod would be a lot longer...but pattern still too wide and again...short of the middle.
And I have used this particular camshaft grind with this particular base circle many times before.
Somethings up. That's the mystery. But I will find it. Just going to use all methods and see what pushrod lengths are called for. Perfect Guinea pig.
Just for grins, check the Milller rocker against another BBC rocker, say like a Crane Gold. Distance between trunion and roller tip c/l's. What heads are these??
When geometry is correct, the pattern will be narrowest...tip will travel least distance across valve tip. (I think you know this) What's the lift?
You're right...something's up. Keep us posted...I'm really curious. :idea: