Bent Pushrods on a rebuilt 318

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Deceus said:
They were shaft mounted rockers and cheap ones at that. They had to use a smaller diameter stud than the aftermarket stamp steel arms because they couldn't find a roller tip arm made for the larger stud size. Obviously not an issue in my situation but that's the explanation.

This thread is getting derailed a bit, I'm not trying to claim that the stamp steel beats out Harland Sharp here. I'm just trying to defend my position here. I'm not crazy for going with FREE.99 over $700 when we're talking 3 horsepower at best here at the rpm ranges my motor is built for. Just for background I'm already over $25,000 into this car that's worth $12,000 at best.



You could never conclude anything with any dyno comparison ever on those grounds. Not sure why it's not sensible. Anything gained in friction loss is lost in the weight difference. It's all a wash in the end for a street motor anyways.

What do I know though, I'm just some dumbass that can't install a rocker shaft correctly.
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I'm not saying not to use what you have. I used stock rockers with Isky 6005 springs and a DC 292/.509 cam in 1980. I turned it 6200-6300 on a regular basis for several years.

Coming home from an Ozzy concert in 1984 I poked a pushrod through a rocker. So I bought Isky ductile iron rockers.

Also, as I pointed out, rocker weight means very little in your application. Now I have to watch the damn video so I can see what they are doing.
 
Went from a off center and wide to in center and narrow using Mikes geometry kit.

This shows how well his kit works.

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Here's what I take away from the EM test.

1.4 hp/CID isn't that impressive.
Peak power was always about 6500, which doesn't surprise me. Do make a hydraulic lifter make power above that is a pain in the ***.
Lots of talk about the "big" cam but never did I hear the specs.
Never showed if they changed pushrod length. I can tell you that the roller rocker needs a different length pushrod, at minimum. I think RAMM did some magnum heads and showed his work (which from what I've seen on here is impeccable) and to get the geometry correct he had to move the rocker stud, which is a pain in the ***, but a must. That will affect the test results.

I come away unmoved by the testing. That's not much cam. Not much spring. Neither of which were the specs provided. 6500 is what I turned my stuff in 1980.

I'm not a fan of needle bearings on a reciprocating shaft. I know it's done, I don't like it. If you are running a Chrysler shaft system, the shaft is bigger than what the GM shaft systems uses. A bushed rocker, with the geometry corrected is the best system. I've run 340 pounds on the seat and 800 plus over the nose at 8500 and never stuck a rocker to the shaft, or even galled one.

IMHO, that test leaves must to be desired and wouldn't base my rocker arm choices on that test.
 
Got everything back together and she fired right up. Sounds a lot better, no more valvetrain noise. Going to pop the valve covers off while it's idling sometime tomorrow to make sure everything is oiling the way it should. I'm just happy the intake isn't leaking for now. Definitely appreciate the solid diagnosis and extra information given in this thread. Some roller rocker arms and geometry work are definitely going to the top of the wishlist but right now I have some harnesses to mount and a k-member to replace. Might even have to buy an EFI kit if I can't get this carb to cooperate with autocrossing. Kept dying on me whenever I'd let off the throttle under hard cornering.

 
Not a good carb for cornering,Fi would be the best but if were you I'd just get holley or similar carb.
 
thesiren74 said:
Not a good carb for cornering,Fi would be the best but if were you I'd just get holley or similar carb.
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Yeah I've been told that. A guy came up and managed to guess the exact carb I had on after seeing it die the way it was. He said he went with a FiTech and considers it the best money he's spent on the car so far. I'm leaning away from getting a better cab simply because if I go EFI I won't have to worry about tuning. I'm leaning towards a Holley Sniper system at the moment.
 
nm9stheham said:
OP, glad you got it going.

May I ask in what part of VA you are?
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I live right at the base of Massanutten in McGaheysville, so not very far from you at all. I'm hoping to make it out to Eastside as soon as the weather allows.
 
Cool! If you need a hand, let me know. I travel a LOT for work so am not all that available. But I CAN be tempted on occasion LOL
 
Remember all those great musclecars from the 60's and 70's ran with stamped rockers...
 
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