How much spring pressure will the stock hemi EX rockers stand . I have seen hundreds of the early fueler , g***er, etc, photos - with engines that had all of the big equipment , blowers , roller cams etc., yet ran stock rockers . I have heard of some that welded a reinforcment rib for the EX rocker, I guess before donovan and all of the High doller roller set ups. Would like to hear from some of you guys that actually werethere and actually ran this in the day . nothing like the truth from the horses mouth. Thanks Mitch
We are faced with the same problem, for a AA/FA cackle motor. Donovan does not make the exhaust rockers any more, and some of these new set ups, (like ***an ) cost thousands of dollars. I have heard of the stock one being reinforced also, just would like to hear some more info on them.
im curious as well. ive been on the phone a few times with junior thompson but never asked about rockers. i believe he still does the "bridge" across the top of the ex. rockers if you send him a set. there is a difference between adjustable rockers and non in the strength department. i know for a fact we run a .500 lift roller isky with install pressure of 225# on un-modified adjustable rockers. but i would like to know the limit.
I wasnt there "back in the day", but I do have the exhaust rocker ribs. As you can see in the picture, one was tig welded with silicon bronze, the other with stainless. They are mild steel and laser cut.
We ran ribbed exhaust rockers back in the '60's. Would handle about 250 lbs. on the seat. Use good CM adjustable pushrods.
Just to let you guys know I ran stock marine rockers in blown alky doing 7.50 7.60 range and never had a failure. When you start getting into high 6 or 700 lift cams then you will have a problem. Its not necessary to run a high lift cam with a 392. If you stay in the mid to high 500 range for lift and 300 or so duration the stock rockers will live. I recommend adjustable marine rockers if you can find them. Bob
I like the welded ones that TR showed -- looks like it would not be too difficult to do, though you'd probably want some sort of stress relief afterwards, shot-peen, etc.. Just make a pattern in CAD and have them laser cut. If somebody wants a pattern/CAD file, let me know - would be willing to design one for free to help out. I had Rocker Arm Spe******ts make my rocker setup -- only took 2 years to get them and a first born , but nice stuff. You might want to give Gary at RAS a call - he knows just about everything there is to know about rockers and builds special setups for Gene Adams and others - worth a call.
I would like a CAD file, if ya don't mind? And those RAS rockers look amazing. If i had the $$ I'd run those
The rib is a great way to increase the Exhaust rocker arm at a minimum cost for the do it yourselfer. What about the Intake would it need the rib or does the Exhuast only need it becuase of the length of the rocker arm ? If you ribbed the Intake rocker arm could you still run the stock style valve covers ? Also when you start getting into the higher lift cams what about the geometry of the rocker arms ?
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