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Discussion Starter · #1 ·
I have a stock 350 in a 72 Chevy pickup. I pull a trailer and would like a little more HP. I have MSD ignition and Edlebrock intake and 650 carb with ceramic headers. Will roller rockers help give me a little more HP? Is it worth the money and effort?
 

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It often gives a little boost in power, but its rarely a good bang-for-buck modification when done alone.

Its main benefits are reduced friction at the valvetrain. Often good for 1-2 hp, but its not a big deal.
 

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Some Punk Kid
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Have you thought about changing the ratio? Im assuming it has 1.5 stamped rockers now. If you wanted to step it up and spend money on rollers might as well go to 1.6 or even 1.7. That would definitely give you a little more power and also slightly bump the power band with that smidgen more dur/lift. Just a thought.
 

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DeathRattle said:
Have you thought about changing the ratio? Im assuming it has 1.5 stamped rockers now. If you wanted to step it up and spend money on rollers might as well go to 1.6 or even 1.7. That would definitely give you a little more power and also slightly bump the power band with that smidgen more dur/lift. Just a thought.
That is not a drop-in modification. The pushrod holes must be elongated to prevent the pushrod from binding in the hole.

tom
 

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And its only worth power if the heads flow better at higher lifts. The stock cam is probably a little on the wimpy side which is why more lift often makes more power, but it bears checking before investing.
 

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TOM is absolutely correct. Bigger ratios can be problematic.

Depending on who did the tests, full roller rockers are good for 2-8 hp.

Most of those old style factory rockers are a little short of the 1.5 they are suppose top be, so as CompCams says, using their rockers helps because of better ratio and some friction reduction. Is $ worth the little gain?

Your best bang for the buck might be a flat tappet "pulling" cam in the 210* range. Places like Summit have an in-house brand where the "full kit" price (cam, lifters, gears) will be about the same price as the full roller rockers and might give you 25 lb ft more torque where you need it.

Don't forget to maximize what you have with a proper carb and distributor curve.
 

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Mertz said:
I was thinking of using stamped rockers with roller tips. Not to expensive. Should I try to go for 1.6 or would that be to much for my stock cam and heads?
I've never seen a stamped rocker with a roller tip. CompCams roller tip/ball pivot rockers are not stamped.

1.6 shouldn't be a problem with a stock cam. Usually lifts up to .475 are ok on most V8s before the keepers hit the valve seals.
 

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Discussion Starter · #11 · (Edited)
They showed a bunch of different kind of rockers on Horsepower TV. The had some that were stamped and just the tip had the roller. I haven't tried to find them yet but I intend to. I would like to see what they cost.

I just checked and Perfromance Parts has them in 1.5 and 1.6. They also show a set that is self aligning. $129 for the self aligning 1.5 $120 for the 1.6 (does say self aligning but they have a cheaper set at $82.
 

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If you dont have screw in studs and guides then you need self aligning roller rockers.They were right I would'nt get 1.6 ratio.Just get 1.5 ratio.
Like mentioned bove a small cam swap would be a significant difference.I had a 256H XE comp cam in my 72' C30 for awhile and it was nice strong torque,good mileage,great overall power.Much more enjoyable to drive than the stock cam.I only swapped it out to a bigger one because I was looking for a more lumpy idle.
 

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Discussion Starter · #18 · (Edited)
After doing some research I found that 1.5 is the best way to go with the ratio. In fact it looks like for low end, which is what I want, 1.4 might be better. I think I will go with the Comps. Does anyone know if they are self aligning? How are they different and how does that work?

The original stamped rockers are not consistant and are about 1.46. The Comps are 1.52.
 

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any thoughts on the fact that the new oils do not serve you well on the flat tappet cams since the cut back on the zinc in the motor oils for smog reasons. I like the idea of roller cam the roller rockers is a bonus. Not sure how envolved that is to add to old flat tappet engine. E dke6bnl
 

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Mertz said:
After doing some research I found that 1.5 is the best way to go with the ratio. In fact it looks like for low end, which is what I want, 1.4 might be better. I think I will go with the Comps. Does anyone know if they are self aligning? How are they different and how does that work?

The original stamped rockers are not consistant and are about 1.46. The Comps are 1.52.
Logically larger ratios open the valve farther and sooner, and that is more power 99% of the time. Otherwise why would anyone put in a higher lift or longer duration cam?

When you see these dyno test guys reduce ratio, or stagger ratios and get more power, all you are seeing is a change in flow balance between their intake and exhaust flows on heavily ported/ custom heads // for the specific combination they have assembled.

The only way that reduced ratios could help you is if you have an out of balance parts combination.
 
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