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Another setback, rocker arm failure

Couple points. First, don't trust anyone's pushrod length recommendation. Get an adjustable length pushrod tool to measure what you need. And measure both intake and exhaust, preferably on every cylinder. Not that uncommon to find you need different lengths. Second, shaft rockers are a whole different animal. They will set you back about a grand or more but they do away with guideplates and hold the rockers perfectly square to the valves. Very nice to have if you want to spend on them.

http://www.jesel.com/valvetrain/index.php/rockers/sportsman-series

The magnum rockers have a reputation for lots of problems. Actually, lots of Comp parts do. For about a hundred bucks more you can get a set of full roller style rockers and will have better luck. Scorpion, Crane and Trick Flow all have good reps. All are supposedly Crane design with Scorpion making them for Trick Flow. Crane uses a newer design with a different oiling relief pattern on the rod end. Whatever way you go make sure to check clearances. Binding on the stud is a big one to watch for.
 
I agree on the don't trust them part! I did originally confirm that the push rod is perpendicular with the rocker at about half open. I understand I will not have a wipe pattern more than halfway toward the intake flange side of the valve tip when the rest of the geometry is correct. However, from what I can gather, that will exhibit the best valve and guide wear scenario on a BBF.
Geometry on the pushrod side of the rocker arm is much more important to be near correct than any other single place (I have read). My research says some compromise is usually necessary to have all the geometries close to right. I bought the push rods per Eddy's recommendation after researching on 460Ford.com others using this combination. However, I did the lazy thing and only checked a couple cylinders when I put it together. My bad.
I also cheaped out on the rockers when I did this. I only have so much "toy" money at any given time. I learned my lesson there too. I needed to get the heads on due to the stock heads (springs/seals) condition or so I told myself.
While I can't afford shaft style rockers nor do I probably need them since this is not a race car, I will spend some cash on good full roller rockers this time!
Again one builder I trust on that forum recommends Comp's Ultra Pro Magnum XD rollers because of the steel body. He says he has used them on many builds with great success and durability.
I have also been researching the guide plates. It seams some guys have to cut the guides to get both rockers lined up, others have had success just spending a lot of time moving them around and to different parts of the heads. I didn't observe any misalignment when I was setting the lash but I was holding the rockers to feel when the pushrod stopped spinning. I didn't go back and make a visual check after setting the lash. I was playing with the screwy ones a little and I could hold them on center when setting the lash but after rotating the engine, they moved off center. I was thinking it was the fulcrum of the rocker but I do think the guides might be off on a couple of the cylinders.
Anyway, I have some work to do! and money to spend...
 
Craig:
If you need any assistance in spending money, I would be glad to help out.
 
Damn, looks like you had a crappy weekend=/

I've been running 7/16" stud Energizer roller rockers on my 331 since day 1. They went on the reworked 302 heads I originally had, then migrated to the Trick Flow Twisted Wedge heads I upgraded to down the road. The rockers are pretty noisy (distinctly different than the clatter from the rhoads lifters), but they seem to be holding up despite regular trips to 6k rpm. I wanted a set of those Comp Cams Pro Magnum roller rockers, but I was trying to keep the build costs manageable.
 
yeah, crappy is a good description.
I read an article on the Magnum roller tip rockers from Hot Rod. Actually they were testing a bunch of rockers but they described exactly what happened to mine. The high lift cam and high spring pressure was too much for the pivot ball area. My son took a few pics for me. You can see they got hot and are worn pretty bad.
Here is a quote from the article from Hot Rod
Pivot ball rockers have been used for years in OEM and lower division racing classes with great success, but our engine combination was just too much. The problem was that the pivot ball that locates the rocker pivot point was not as efficient at reducing friction as rockers with a bearing trunnion. On the dyno, the high spring pressures combined with the large amount of lobe lift burned up the fulcrum area of the rockers.
rocker 1.jpg rocker 2.jpg
 
Looks like a full roller rocker is in your future. Don't discount scorpion because of there cheaper price. I know a lot of guys that running them with success.


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Looks like a full roller rocker is in your future. Don't discount scorpion because of there cheaper price. I know a lot of guys that running them with success.


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thanks for the input. good to know. I'm still debating what I'm gonna do.
I think I need to pull the engine to do the trans, just to get access to the firewall for the hydraulic clutch. I might just put a V6 in it
 
will it be up and running by mid June?.....and how much do rides cost?
He's supposed to be bringing it to Kansas City for the power tour!
It's not looking good. The trans is still in it, the rocker arms are not. The carb is messed up too. The rockers will need to be replaced, no fix for them. The carb might be fixable. The trans swap is just going to be too much work. I know 43 days is a lot but I am not home most of those 43 days!
We are going on the Power Tour. I could drive the wife's 07 but new cars are boring. So we are going to drive the 72 Cheyenne (unless it breaks before then).
 
I hear ya. That's a lot on anyone's plate especially since you travel so much.

When you really think about it in those 43 days I'll probably only have 5 or 6 days off myself. That's not much to work with when you have a family and many other things going on.



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I hear ya. That's a lot on anyone's plate especially since you travel so much.

When you really think about it in those 43 days I'll probably only have 5 or 6 days off myself. That's not much to work with when you have a family and many other things going on.



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yes, exactly!. I thought I had it all sorted. The shake down runs proved me wrong. I have really spent too much time helping my boys and neglecting my stuff. But we were hoping to have all three on the tour and failed miserably. The 99 is too far from finished, mine is a little self induced. I beat on it whenever possible! But I have started taking it all apart. So it will be ready next year! I did get 6 good long hauls out of it with little to no problems. I hope you and Terry can say the same thing!
 
Well I'm hoping my car holds up. I've put about 150 miles on it trying to test stuff. Each time pushing it a bit harder to see what it can handle. If the weather would start cooperating is like to take it out on a long drive maybe a couple hours and see how it feels.



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You should be okay. My car is a relatively old build. The drive-train was all built in 1990. The engine in 99. I have put a lot of miles on it and beat on it pretty hard. It's starting to catch up to me!
 
Well my engine is out of an 88 gt and I have no idea if it's ever been rebuilt or how many miles are on it.

The trans was rebuilt last fall.


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Well my engine is out of an 88 gt and I have no idea if it's ever been rebuilt or how many miles are on it.

The trans was rebuilt last fall.


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have you had any hot days yet? My car has never liked sitting in traffic in the heat. There is a lot of that on the tour.
 
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