Which Roller Rockers should I get?

[decooney]

Brent,
I tend to agree with these guys. Throwing more new parts at it might not be the most prudent thing to do at this point. IMHO Time for some real root cause analysis by a qualified FE engine builder. If it were me, the motor would not go back in the car until it had been run on a stand for some time, and thoroughly checked...

What might seem like the fix right now, might not be, and you could end up right back at square one again; and even more flustered.

When Tom at FE Specialties blueprinted my motor, we ran it (on the stand) for over two hours checking the oil to the top of the rockers, shafts, top of the heads, drainbacks and more. He will not build motors any more without doing this because of problems just like this and due to the variances seen in parts manufacturing and quality control issues.

I don't know if you've talked with Tom Lucas or George at Gessford a bit more, but I bet an experienced, well-trained eye will find your problem in less than one hours worth of shop time.

[Brent Mills]

If there's an oiling problem, it's because of the rockers. My engine was on a test stand for some time, and in the analysis, he indicates that plenty of oil is making it to the top end components, so if it isn't now, the rockers are the only thing that changed. If it's not an oiling problem introduced by the new rockers, then it's a hardening issue. Either way, I'm concerned and want to get something different.

Secondly, per my builder, who is a compitent FE builder (been building them & racing them for years and has plenty of happy FE customers), the Harland sharp rockers I sent him indicated that the adjusting ball on that rocker was ever so slightly bigger than the rest as I understand it, causing the cup on the push rod to break. Now, until that pushrod broke, it ran great. I know the clearances were good between the manifold holes, etc. Maybe I am being stubborn and pig headed, but I have thought about this day after day now, and logically, it just can't be something other than a hardening issue or an oiling issue, neither of which I had before the new rockers.

[Anthony]

I don't know about the cup/ball size being wrong,

but, with the ball and cup pushrods, you need to make sure the cup part of the pushrod doesn't bind on full lift on the side closest to the rocker shaft. The cup can bind against the underside of the rocker. You need to check every rocker arm for clearence. G. Anderson told me with the Dove rockers, you should have at least 3 threads showing below the rocker on the ball stud to make sure you have enough clearence. You may need to run 0.100" shorter pushrods.

Comp Cams FE rockers are made by Dove for them.

427 heads have wider spaced valves than 390/428 heads, both the intake and exhaust valves are farther from the centerline of the chamber, therefore the rockers need to be spaced differently. With edelbrock heads, the Intake valve is spaced from the centerline of the chamber like a 427 head. The exhaust valve is spaced like a 428 head.

[John 550]

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[John 550]

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[hdheritage97]

If you decide you want to go with Doves, I have a brand new set right here beside me that I'll let go reasonably, let me know.

Cliff

[Keithc8]

Brent, Why don't you let me fix your engine for some advertising on your web- sight. I am sure we can solve the problem and find you some HP. I believe we need to go into the engine and check everything out and put it back together where we know what we have and what is causing these problems. Any of the rockers mentioned should work unless the heat treat is wrong. The biggest problems with most FE rocker systems is the one long rocker shaft and only four 3/8 bolts holding it down to the head. The stock type systems seem to work fine untill you need to run a lot of spring pressure and turn a lot of rpm's. You can give me a call if you like at 870-246-7460. I do not know how to get ahold of you other than this. Good luck

[jrussell]

Brent,
I have just been reading this thread and came upon the response to you by Keith Craft. Logistics aside, if you can work out a trade and get the engine sorted out at the same time without throwing more $$ at it seems like a win-win to me! At this point, it seems to me that you are about due for a win-win!!
Your Texas friend ( at least one of them)
John Russell

[Brent Mills]

I missed the last couple posts on this thread. Keithc8, thank you very much for the incredible offer! Wow! Hope I never have to take you up on that.

POP sent me new adjusters and I figured I would throw them on there just to see if they did the same thing, as I suspected the last ones hadn't been hardened properly. I checked for good oiling at the cup of all of them (pre oiled with drill), changed oil & filter, added GM EOS treatment suggested by my builder and George Anderson. About 100 miles later and it's still running well. Was done for in about 5 miles last time, so I think I might have this thing beat.

[Rich]

"About 100 miles later and it's still running well. Was done for in about 5 miles last time, so I think I might have this thing beat."

Does this mean you may show up at Red Hook on Sunday? I'll buy the 1st IPA.

Rich

[misfit41]

Brent
are you ajusting the clearance with the engine at operating temps ? thats a big deal with alloy heads,,my bet either that,or the push rod lenght is your problem,,it isnt the rockers,,
Tk

[blown]

i have all 3 differant rockers and never had a problem and i use my fe cars i think you have a problem like wrong push rod lenth .all rockers will go much more than 500 miles.
after reading the thread good i can say your eng. builder is not very bright but i would bet the holes for the push rods in your intake are to small it is a very common problem with moderate lift cams and new intakes i dont like eng. builders that tot there own horn there is always one that will make you look stupid .

[Brent Mills]

The adjuster balls on two rockers were too big (Harland Sharp) and broke pushrods. I changed to a different style rocker and the cups were not hardened. Plenty of pushrod clearance

New adjusters and all seems to be ok. Builder IS bright....NOT an engine builder problem.

[misfit41]

just an afterthought to this post,My racer friend {Nd Copley}whom I often refer to was in yesterday,he has had push rod rocker problems all year,hasnt finished a race becaue of it,this is a guy who has raced 427's for 35 years and was stumped,tried everything,rod lenght,different brand rockers,,etc.
After once again thinking he found the culprit ,he broke a rocker during a 6000 rpm hot lap,finally a sharp engineer noticed a scrape on the side of a seemingly good push rod {new at that}and figured out the rod had been flexing,after checking rockwell hardness,it was in the 20's,dove uses steel in the 60-65 rh range I think,after calling Earl at Dove enginering and having him check his rod stock blanks,they learned the steel was mistempered or mismarked by the supplier.I wonder if this could have happened to others too,granted Nd Copley has tons of spring pressure in his roller motor,but soft is soft.
he also shared with me that an alloy head 427 will "grow" .0010 from cold to operating temp,so always adjust the valves hot.
Lastly he got a set of unfinished rods from comp cams,65 rh and you cut to lenght and press in the top fulcrum,seems like the way to go to me.Tk