i just put in a lt1 cam and was wondering what roller rockers would work for me. the push rods are the same length and everything. would 1.6 roller rockers work? and what brand is a good one?

 

Aftermarket Product Review might be a better forum to check.

 

1.6 rockers should be a good addition to an LT1 cam just make sure you have springs that can handle that lift and make sure they will clear the stock heads (assuming they are stock). If the car is street driven I think you'll want to look for some steel ones and not aluminum because the aluminum ones supposedly wear much faster, I've heard the Comp Magnums are good.

 

Yes roller rockers are great. I would go with the proform full rollers from jegs. They are $170 I believe... needle bearing roller tipped and all that good stuff. I do not see how aluminum ones wear faster... where did u get this information from? go to members.fbody.com/camaroguy7 and check out the pics of my car. I have the rockers in a pic at the bottom. Those are older pics since I never got a chance to get pics of my new setup b4 I blew the car up... literally.

 

With aluminum it's not really wear it's fatigue you have to worry about. I don’t know how many miles people usually get out of a set of aluminum but I know that over time the aluminum is going to weaken. These things are going up and down thousands of time per minute which puts a lot of stress on weak aluminum. I’m currently a third year student in mechanical engineering I just did a tensile stress on aluminum the other day. Aluminum is a very ductile material which means it stretches so you might have to worry about that too. I would go with the Comp Cams Pro-Magnum Self-Aligning Roller Rocker Arms, 3/8" stud, 1.6 Ratio they are on sale right now over at thunder racing.

 

If you've got your stock heads you're going to want to make sure you get ones fore centerbolt valve covers. IIRC only comp cams and crane cams make 1.6 full on rollers.

-chuck

 

Comp cams now makes them also.

Pro Magnum full rollers 1.5 or 1.6

These will be my next ones.

DM

 

Go to www.enginekits.com and download their catalog. It's a PDF file so you'll need Acrobat Reader

In there you'll find a set of stamped steel 1.5 and 1.6 self-aligning roller tip rockers for ~$90. I have a friend using them on his '69 (not self-aligning) and they work great.

DO NOT use Proform rockers. I don't care if someone pays you to use them. They are very weak and they do break. Do an internet search for Proform and Break. You'll find a lot of results.

The problem with full roller rockers isn't whether they're aluminum or S/S, copper or brass, it's the needle bearing fulcrums that are the problem. They wear out. AAMOF, Comp Cams clearly advertises rebuild kits for even their ProMagnum rockers. If you want maintenance free rockers, stick with stamped steel w/roller tips.

Also, be aware that when you run 1.6 rockers, the pushrod is closer to the rocker and can bind up on the pushrod slot in the heads. Normally the slots have to be elongated, but if you check to make sure, you may not need to do that.

 

With high quality aluminum fatigue will not be a problem unless you run about 200,000 miles. AJ_92RS was right about them wearing out If i were you and you were on a budget i would pick up a set of these
http://www.flatlanderracing.com/scorpionrockers.html The Lt1 guys have very good luck with them. I actually just found out about them today and i saw some close up pics of them and i was impressed with the quality of the arms. I may just get a set over the pro - magnums.

 

What is the difference between roller rockers and the stock rockers? Can any horsepower be gained by putting roller rockers on an engine with stock heads and cam?

 

Yes it can. You will see that on the end of a roller rocker it has a roller that helps reduce friction and helps keep valve timing very accurate. The stock pieces can actually flex a lot and rob you of power. They only have an indent on the end and drag over the top of the valve and spring. Since you have the LT1 cam I would go with 1.5rr's. 1.6 will make the lift on that cam a bit to much for the stock heads. You may be able to pull it off but some serious measuring will need to be done to make sure that you are withing spec.

 

Hey ShiftyCapone

I have a 1998 IROC with a 305 TPI. What roller rockers would you recommend? Also could you provide a brand and part number.

Thanks,
Joey

 

OOOOPsss I mean 1988...

 

I would look at the Pro Magnum series from comp cams. They are a little heavier than the aluminum ones but are stronger and less likely to fail like the boxed aluminum version. They have some that retail for 150 and 200+. Flip through your jegs and check them out. If your car is otherwise stock you may want to consider another mod.

 

actualy, the pro-mags are lighter than the alum ones. because it takes quite a bit less material.

 

I thought so too until they used both on horsepower TV the other day. They said the pro mags were slightly heavier but that all of the weight was centered on the fulcrum which made them act as if they were lighter.

 

the bearing used will make a big diffrence also, were the weighting them with or without the fulcrum bearing?

 

I am pretty sure with but I could be wrong. They had both sets on hand that were fully assembled. They could be wrong though. I bet they are both very close in weight.

 

yeah, but like you mentioned, the location of the mass is what makes the diffrence. truth is, it isn't the mass of the object, it is the moment of inertia, as basicly you are dealing with a rotating mass.

 

Correct. But there is some loss because you have to change the direction of that rotating mass very quickly. So even though the bulk of the weight is at the center of mass you still have to change its direction with more energy than you would with a lighter rocker. The difference should still be small to negligable and does not take away from the power gains of a precise rocker.

 

come on shifty, aren't you a ME major?

which takes less energy, 10lbs on a 50ft pole, or 50lbs on a 1ft pole

the moment of intertia is what you really need to look at, although you are right this point is VERY mute, the large gain comes for the fulrcum bearing.

 

Yea I am unfortunatly and I will be the real deal in 6 weeks. I am assuming the rockers to be the same length with their appropriate centers of gravity in the same spot. Ok enough nerd talk. Bottom line, anything better than stock will do quite nicely.