Technical Anybody have experience strengthening stock hemi exhaust rocker arms!?!

Ron Ceridono's Hemi book mentions adding a chromoly strengthening rib or fin, heliarc welded to the stock (Chrysler) exhaust rocker arm's body. I'm ***uming that the exhaust rocker arm is forged, but little information seems to exist about the best filler rod and welding method that should be used to actually add strength to the part.

Is there anybody on the HAMB that actually has experience strengthening, and then abusing the stock exhaust rocker arms on a (Chrysler) Hemi? If so, how exactly did you go about it so that those of us with the desire may follow in your footsteps? Thank you!

 

TR Waters on here does that. Contact him
http://www.trwaters.com/?s=rocker+arms&submit.x=0&submit.y=0&post_type=product

 

He sells the fins, but I don't think HE does the welding. In the interest of "keeping the firepower lit", maybe he'll chime in.

 

You check the hemi tech index?

 

Yup! That's where I found out about 73RR (Gary Stauffer) doing the adjustable rocker arm conversion, which led to a discussion about welding the chromoly fin, and he said he's heard a lot of conflicting info on process/filler, and so I made the thread. If Scooter would like to move this into the Hemi Tech, I'm cool with it, but we need to actually get some info in here first...

 

Gary Roushkolb from Wichita welded mine on but I can't remember what he used for filler. I sent him a text so lets see if he can remember.

 

Awesome! Keep us posted? They're holding up well I'm ***uming?

 

Not sure why you would want to do this? I have never considered running stock rocker arms. The aftermarket pieces are available and arn't terribly expensive. My hemi experience started in 1982 and ended in 2002. Blown alcohol and injected nitro hemi's. Never broke one aftermarket rocker. Why reinvent the wheel? Just saying...
Maybe the "cl***" you are considering requires "stock" rockers? Dunno!

 

While I was able to obtain a set of Donovan's (7 very cheap at a swap meet; one very expensive from Hot Heads), I have never been able to find them available (let alone cheap) anywhere. Do you have a source?

 

not terribly expensive is a subjective term based solely on how deep of pockets a person has. $500 is not terribly expensive to me. $5000 may be not terribly expensive to the guy that drives a 1.3 million dollar car. I think we need to see a price and location of where these after market rockers are coming from.
I am in the market to either convert mine to adjustable for $600 or locate some after market ones.

 

unless you run nitro why would you want to do this? that is out dated technology when that was all that was available. and if you do run nitro why not after market rockers. if you cant afford after market rockers you certainly cant afford a nitro car. nitro cars dont like cheap parts. no one has the money to do it right the first time but they always find the money to do it right the second time. i run missle rockers to avoid a disaster.

 

When expense is considered don't you need to factor end result? Does anyone think they can pay someone to "reinforce" a set of Hemi exhaust rockers for free and what about the end product? In 35 years of racing I don't think I ever saw a welded set of hemi exhaust rockers on a competative hotrod. Must be a reason...my guess is the welded rocker was junk after the heat was applied.
Obviously on occasion the stock exhaust rocker broke but it only happened in "hopped" up condition. Initially the beefed up exhaust rockers came from nitro engines (back in the day) when cylinder pressures were off the charts. The exhaust rocker, which is quite long, failed when the cam tried to open the valve into a rapidly expanding box! Just saying...

 

Rebuilding a set of rockers (adjustable or non) with the usual performance upgrades (HC shafts, bushed and honed arms, resurfaced tips, etc) seems to run about $700. Start with a set of non-adjustable rockers at $100-200 and add adjustable pushrods, and you're at about $1000 all in. Start with a $700-800 set of adjustable rockers and you're closer to $1500 all in. Adjusters can be added to the factory non-adjustables for $300 and change, but the consensus seems to be that factory adjustables are stronger...hence my question about the fin.

The cheapest set of aftermarket adjustable rockers on the market today, that I have seen anyway, were about $2500. Not only is that an extra $1000 for only marginally better performance (on a hot rod), but I'm not generally one to buy "the cheapest" anything, and some of the billet aftermarket setups creep up towards $4,000 and more. I don't know a damn thing about them. But that's a lot of dough...

 

"Not terribly expensive" IS a relative term. I bought the seven Donovan's at a swap meet for $35, and the 8th one from Hot heads for $80, so you can see I'm pretty cheap. They are in the engine in my dirt car, though, while not a nitro burner, is quite healthy (Engle roller cam, 12.5 to 1 pistons, magneto, and the usual stuff). Broke an exhaust rocker arm the third time out, found the Donovan's, and never looked back. We run adjustable push rods which aren't as big a pain as some say, but I like to tinker in the garage in my spare time and a valve adjustment once a year ain't bad, once you bend up the right set of wrenches.

Even with the roller cam, I have the rev limiter set to 5500, and we still broke a rocker, so maybe a little extra on a street engines with some mods is still warranted.

 

Can't comment on any thing but the filler rod to use...Eutectic 680..

 

Well hey, that's somethin'. I don't know enough about the metallurgy to question that recommendation. I know the fins are chromoly. Are the rockers forged?

 

700-800 dollars for factory adjustables. i will take every set you have. i have yet to sell a set for under 1500. pm me on how to get them.

 

I have yet to see a set go that high, and I haven't seen a set recently actually sell (not talking people's asking prices) for much more than $800. One ended on eBay the other day for $800 with 0 bids. Where were you?

 

I don't have any experience with factory adjustables. Can anyone tell me if they are any stronger than factory non-adjustables? After I broke the one exhaust rocker, just about everyone I talked to said the factory exhaust rockers were marginal in an engine with any kind of valve train update. Just look at them and they appear kind of flimsy (long and spindly). I have another 331 ('56 truck) engine I may do if I can find enough parts cheaply enough, and am now wondering whether I should be looking for a set of factory adjustables or continue on my quest for another old set of Donovans and a set of adjustable pushrods. Any advice appreciated.

 

Its all about spring pressure. If you are making a flat tappet engine for the street, the stock stuff should be fine. I have spent a lot of time and $$ on this over the last year. When I decided to go with a roller cam with 270lbs on the seat and 700lbs open, the switch to aftermarket setups are a must. I spoke with Mitch Rish who ran a blown dragster for years and he thinks up to 450lbs open on stock arms is ok.

Here are the sets and good and bad of arms that I can offer - feel free to disagree - just telling what I ran into :

Very nice rebuilt stock adjustable - sold them on Ebay for $1250 to fund the billet rockers. Wish I had kept them now - was a nice set.

So my first uninformed purchase - ***an rockers. Got from a top fuel car when they were done with them for $1500. Big mistake! These are not oilers. There is NO oil coming to the heads with these. They are meant to be torn down every run at the drags. (These are for sale ) There is a guy on here called Tricky Steve - he drilled these and made them oil. Said it was a pain


Finally was talking to Bob at Hot Heads and he convinced me Missile was the best option for high spring pressure oilers. Couldn't be happier with them. Not cheap but cheaper than making wrong decisions until arriving here


Hope this saves someone some trouble someday. Its not easy finding out all this stuff. The Tex Smith book doesn't go here.

 

Those Missles are sweet, but I just don't have the budget for $3000+ worth of rocker arms, and I don't think many other folks on here do either.

Several people have said that "the stock exhaust rockers are weak", or that they're only good for **X open spring pressure, or that...you get the idea.

Are the stock ADJUSTABLE exhaust rockers stronger!?! They look more substantial...I finally broke down and bought a set. At what point does their strength come into question.

Also, Kerry posted another thread back in 2012...I just found it, and it touches on the whole fin welding deal briefly before going off the rails like this one has...here's the link:
http://www.jalopyjournal.com/forum/...valvetrain-in-the-digger.673636/#post-7483276

 

FWIW, I'm not trying to argue with you...it just seems that everybody lumps stock non-adjustable and stock adjustable rocker arms together in terms of strength, but the adjustables should be somewhat stronger. When somebody throws out a number like "450 lb open" being the upper safe limit, which piece are they referring to? Sorry, not trying to beat anybody up, and there are always other factors to be considered...I'm just trying to clear up what I (and maybe some others) see as a misconception. Thanks!

 

No worries - its an interesting subject for our time since back in the day they didn't have all the springs an stuff we can try out today. They obviously were running rollers back then but how much spring was available ? When you want more pressure, you need a longer valve for the bigger spring and now the stands need changes to fix the geometry. It snowballs quick.

And then - if you do research on roller cam spring rates, you can find lots of differing info .

http://www.enginebuildermag.com/2012/08/recommended-valve-spring-pressures/

Is that for real? Ive seen guys run rollers with less pressure for 4 years. I'm interested in learning as much about this subject myself. This build is an all out drag race engine. For the street, it would be way cheaper if a roller can run lighter pressures and then use stock arms.

 

I've never built an all out race motor before. This will probably be the highest horsepower motor I've ever put together, but I'm using an off the shelf cam, and everytime I've done that I've had good success running the manufacturers recommended spring rates. Is that totally naive of me?

The two cams I've been recommended are both solid rollers from Crane, and Crane spec'd way lower spring pressures than your link would recommend, which seems to mirror your experience as well.

The cam Crane's Chase Knight actually recommended was a 250° @ 0.050" duration on a 108 LS, 0.552" lift, and then set it to 0.025" lash to effectively limit the lift to 0.527", thus keeping within the theoretical max of stock length hemi valves. Chase recommended a 180 lb seat/400 lb open spring for this cam.

The Crane cam that Bob Walker recommended was a little smaller, with 246° @ 0.050" duration, and 0.495" lift. He said not to go over the 0.500" mark with stock valves and rockers. Several others seem to agree, though some folks are doing it with at least a moderate degree of success. The springs Crane specs for THIS cam are a 150 lb seat and 290 lb open.

 

Casey,
It would be nice to know exactly what your engine is it being built for : street? strip? a combination of both? What kind of a car is it going in? Unless you're building an all out drag motor, a lot of what has been discussed on here lately may be expensive overkill.

Tubman

 

Casey- Have you talked to Gary in depth about this? I'm sure everything will be gone through as far as prep within the heads themselves,and probably a valve upgrade will happen.(seem's the norm with a step up from stock).But- I don't have a rpm engine,so the rate's,and longevity with what your plans are, are factors like everything else......Our own Kerry is doing it,others are doing it, Heck- look at what Garlits and the pioneers did.
I think you'de be fine with your plan......I'de see what Gary, or Tom has to say.
Worthless rambling Wednesday here.......

 

Tubman,

This motor will go in a Model A coupe and with a little stretch and some basic streamlining I plan to try and get kicked out of the USFRA's 150 mph club at Bonneville. I say that in jest, or course. I will respectively do my best to not abuse their gracious speed limit of 159.99 if I can even get up there. Then hopefully with a tire and gear change, I want to run it (non-compe***ively) at the local drag strip. It will see very limited street use.

The motor is (going to be) an extended block 331, 10:1 compression, '54 heads heavily ported, 2.06/1.80 valves, one of the aforementioned camshafts, and mechanical injection. Trans will be a Tremec close ratio TKO. Rear is a 9", geared to the application of the day.

I have talked to Gary extensively, so much so that I fear he's started to dread my emails, but he graciously answers every single one of them. He recommended the fin, but said there was too much conjecture to make a recommendation on welding process and filler, which is why I started this thread. Then I talked to the OTHER Gary at Rocker Arms Unlimited, and he wasn't super keen on welded rockers, and instead said I'd be better off to find the factory adjustables. I've talked to Tom a little bit; mostly about his main cap girdles though...he seems harder to get a hold of.

I agree that my combo should work with my modest power goals, but there are so many conflicting opinions out there. So when I say that fancy billet rockers aren't in my budget, I mean that I will compromise other aspects of my build to live within' the confines of the weakest link, not that I will go out there with a ticking time bomb in my engine.

My biggest dilemma RIGHT NOW, is whether I'm better off rebuilding this set of stock adjustables I just dropped $800 on, or rebuilding a stock set, after I weld the fin and convert them to adjustables. Either way, I will be somewhere between $1200-1500 in a completed set, which is a lot of money to spend, only to abuse and break them.

 

REBUILDING a stock set of adjustables? Maybe I'm reading wrong here-,but were they re-conditioned? IE= shafts/faced/checked?. Just "stating" that a stock shaft can be converted to adjustable,then a custom pushrod could be eliminated,as the adjustment is in the arm itself.....
Look at what Tom did to Kerry's shafts,and what he's doing.
I'de say if he's on it,and then some,so if it's working for him in the digger,and what your doing,you should be good.
Many ways to skin the perverbial cat.......Cake and eat it too......Get accomplished with what your goals are......
Hell,it's after noon-gotta watch Jerry Springer

 

Wait, now I'm confused. I have two sets of rocker arm ***emblies. One set is a factory Chrysler non-adjustable as found on 99% of these motors. The other set is the rarer factory adjustable as found on most Marine and some of the higher performance engines. When I say rebuild, I mean that the shafts will be hardchromed, the rockers will be bushed with oilite bronze bushings, and their tips will be resurfaced. Whether I do this with the adjustable set or the non-adjustable set is what I am trying to decided. Regardless of what Kerry is doing, at least one well respected person in this industry told me I would be better off doing it different. I just wanted to know if anybody else shared that notion.

 

Given what you're planning, I think you are wise in considering something stronger than stock exhaust rockers (the intakes seem to be OK). Do you have a stock non-adjustable rocker to look at? If you do, you should throw a caliper on it in various places to see if it is any less robust than the adjustable. If Chrysler made them adjustable because of increased performance, they probably made them with increased strength. Plus, I'd like to know myself. I have been looking for another set of Donovans for the last 10 years, and they just don't seem to be out there. I have seen stock adjustables, however. In the final ****ysis it would really be nice if someone with real world experience with the welded on ribs would chime in.