Roller Rockers Geometry
OK, upon further inspection it appears that the old adjuster screw and the newer one are only different in the height of the screw above the threads. The nuts, thread length and the ball end are identical. They just got rid of extra weight on the screw that is not needed. Here is a crappy picture of them side by side:
These two pics below are of the same rocker. I pushed the roller pin all the way left in one pic and all the way right in the other. Notice that the pin that the roller rides on is sticking out to the left in one pic and centered in the other. It is loose.
I spoke to Bob Mazzollini last year about all of this and he uses the Pro Magnums on some lower level high performance engines with the cup end adjuster screws. He said he prefers them. I did not ask why. He was surprised to hear what I had been through with them but he had not used the Magnums, just the Pro Magnums. I believe that all of the new Pro Magnums have a different way to retain the pin, but I have not gotten a look at them, so I'm just guessing.
He uses T&D on high end motors.
I honestly believe you can't beat the Crane Gold Race Rockers for the price. Mercruiser uses them exclusively because they just don't fail.
Since you are happy with the geometry, check your pushrod length:
Roll the engine over so the both valves are closed on the #1 cylinder.
If you have an adjustable pushrod, pull the left rocker shaft off and remove the pushrods.
Put the adjustable pushrod in the #1 exhaust lifter (and one in the #1 intake lifter if you have another) and install you rocker shaft.
You should have your rockers adjusted at the recommended thread protrusion.
Tighten the adjustable pushrod(s) until they make contact with the rocker.
Remove your rocker shafts and pushrod(s) and measure them. Add the preload amount to that measurement. That is the correct length for your motor.
As far as Comp Cams goes, I don't like them and I no longer deal with them. They are the self-proclaimed leader in valvetrain technology....what a crock!
For years they told us how aluminum rockers suck and now, all-of-a-sudden, they have discovered a way to make them so that they are good????? They just got sick of losing too much business to Crane and others who make aluminum rockers...that's my opinion.
I don't like these giant conglomerations that buy up every company they can find just so they can make more money. Hooker Headers used to be great. I had a set of Super Comps on my Dart for years and they were rusty and dented so I bought new ones....same part number...only now they are made elswhere and they would not fit worth a crap and they clocked the collectors different so I would have had to cut my exhaust and re-weld the collectors. I sent them back and bought TTI's.
I hope this is helpful....maybe Comp would be willing to swap them for Pro Magnums???
OK, upon further inspection it appears that the old adjuster screw and the newer one are only different in the height of the screw above the threads. The nuts, thread length and the ball end are identical. They just got rid of extra weight on the screw that is not needed. Here is a crappy picture of them side by side:
These two pics below are of the same rocker. I pushed the roller pin all the way left in one pic and all the way right in the other. Notice that the pin that the roller rides on is sticking out to the left in one pic and centered in the other. It is loose.
I spoke to Bob Mazzollini last year about all of this and he uses the Pro Magnums on some lower level high performance engines with the cup end adjuster screws. He said he prefers them. I did not ask why. He was surprised to hear what I had been through with them but he had not used the Magnums, just the Pro Magnums. I believe that all of the new Pro Magnums have a different way to retain the pin, but I have not gotten a look at them, so I'm just guessing.
He uses T&D on high end motors.
I honestly believe you can't beat the Crane Gold Race Rockers for the price. Mercruiser uses them exclusively because they just don't fail.
Since you are happy with the geometry, check your pushrod length:
Roll the engine over so the both valves are closed on the #1 cylinder.
If you have an adjustable pushrod, pull the left rocker shaft off and remove the pushrods.
Put the adjustable pushrod in the #1 exhaust lifter (and one in the #1 intake lifter if you have another) and install you rocker shaft.
You should have your rockers adjusted at the recommended thread protrusion.
Tighten the adjustable pushrod(s) until they make contact with the rocker.
Remove your rocker shafts and pushrod(s) and measure them. Add the preload amount to that measurement. That is the correct length for your motor.
As far as Comp Cams goes, I don't like them and I no longer deal with them. They are the self-proclaimed leader in valvetrain technology....what a crock!
For years they told us how aluminum rockers suck and now, all-of-a-sudden, they have discovered a way to make them so that they are good????? They just got sick of losing too much business to Crane and others who make aluminum rockers...that's my opinion.
I don't like these giant conglomerations that buy up every company they can find just so they can make more money. Hooker Headers used to be great. I had a set of Super Comps on my Dart for years and they were rusty and dented so I bought new ones....same part number...only now they are made elswhere and they would not fit worth a crap and they clocked the collectors different so I would have had to cut my exhaust and re-weld the collectors. I sent them back and bought TTI's.
I hope this is helpful....maybe Comp would be willing to swap them for Pro Magnums???