Small block rockers?

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1bad360duster

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Anyone use the comp magnum shaft rockers? I see they only come in a 1.5 ratio but I can get a cam close to the lift I want with that. Prw makes a 1.6 but wondering how the quality of the two stack up? If I’m getting the lift I want with the 1.5 is there any advantage to going 1.6? I know it can effect more then just lift possibly? Thanks
 
1.6 is supposed to have a faster ramp rate (same centerline) just due to the dynamics of the leverage and possible a little more duration for the same 1.5 cam. If you don't run a crazy spring, they would work fine.
 
I have the Competition Camshafts Magnums. Just got the engine back and won't get it put in the truck for awhile. Wist I could give you a report. They looked nice. Looked/felt like a quality product. That's all I can add.
 
I have comp rockers on my LA 408.
Street / strip duty. Have not had any problems.
I would recommend them.
 
1bad360duster said:
Anyone use the comp magnum shaft rockers? I see they only come in a 1.5 ratio but I can get a cam close to the lift I want with that. Prw makes a 1.6 but wondering how the quality of the two stack up? If I’m getting the lift I want with the 1.5 is there any advantage to going 1.6? I know it can effect more then just lift possibly? Thanks
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Either of those rocker arms will perform well if they are set up correctly. Usually they require the rocker shaft to be moved up and toward the intake side of the head. I have the Comp version but have not installed them yet because the roller tip was so far toward the exhaust side with Edelbrock heads.
I suggest you call Mike at B3 Racing Engines. You can purchase the rocker arms through him and purchase a correction kit at the same time. That is my plan as well once funds allow it.
B3 Racing Engines LLC - Performance Engine Building and Mopar Valvetrains
 
Thanks for replies guys, anyone have experience with the Mancini brand Harland sharps. They look nice for the price
 
Bobzilla said:
Either of those rocker arms will perform well if they are set up correctly. Usually they require the rocker shaft to be moved up and toward the intake side of the head. I have the Comp version but have not installed them yet because the roller tip was so far toward the exhaust side with Edelbrock heads.
I suggest you call Mike at B3 Racing Engines. You can purchase the rocker arms through him and purchase a correction kit at the same time. That is my plan as well once funds allow it.
B3 Racing Engines LLC - Performance Engine Building and Mopar Valvetrains
Click to expand...

We had to use lash caps on the Speedmaster heads with the Comp Cams Ultra Magnums. Didn't know about B3. Hmm.
 
go-fish said:
We had to use lash caps on the Speedmaster heads with the Comp Cams Ultra Magnums. Didn't know about B3. Hmm.
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The Comp rockers are a good choice. I prefer the option of higher ratios not available from Comp, though.

Just an FYI for those interested, adding lash caps with a roller rocker will actually make the true running geometry worse, regardless of where the pattern is on the valve tip. See our tech articles for more info.

Also, a steel rocker has a much longer fatigue life than an aluminum rocker. If you want to drive the wheels off of it, and have low maintenance and long life, a steel rocker will last much longer.

Lastly, we will not make geometry correction kits for Speedmaster/ProComp heads, as manufactured. We have a file with a bunch of broken rocker shaft photos, due to the incorrect machining of the shaft mounting radius in the pedestals. That allows the shaft to rock in the saddle, causing the bolts to loosen. Only if this machining is corrected will we make geometry correction kits. This is not new, and has been known for years to be an issue.

If anyone has questions, after reading through our tech articles, feel free to call. I would be happy to provide an explanation to answer those questions.
 
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B3RE said:
The Comp rockers are a good choice. I prefer the option of higher ratios not available from Comp, though.

Just an FYI for those interested, adding lash caps with a roller rocker will actually make the true running geometry worse, regardless of where the pattern is on the valve tip. See our tech articles for more info.

Also, a steel rocker has a much longer fatigue life than an aluminum rocker. If you want to drive the wheels off of it, and have low maintenance and long life, a steel rocker will last much longer.

Lastly, we will not make geometry correction kits for Speedmaster/ProComp heads, as manufactured. We have a file with a bunch of broken rocker shaft photos, due to the incorrect machining of the shaft mounting radius in the pedestals. That allows the shaft to rock in the saddle, causing the bolts to loosen. Only if this machining is corrected will we make geometry correction kits. This is not new, and has been known for years to be an issue.

If anyone has questions, after reading through our tech articles, feel free to call. I would be happy to provide an explanation to answer those questions.
Click to expand...
Thanks for the info! How do the promaxx and edelbrock castings stack up? I heard they should be very simpliar castings.
 
B3RE said:
The Comp rockers are a good choice. I prefer the option of higher ratios not available from Comp, though.

Just an FYI for those interested, adding lash caps with a roller rocker will actually make the true running geometry worse, regardless of where the pattern is on the valve tip. See our tech articles for more info.

Also, a steel rocker has a much longer fatigue life than an aluminum rocker. If you want to drive the wheels off of it, and have low maintenance and long life, a steel rocker will last much longer.

Lastly, we will not make geometry correction kits for Speedmaster/ProComp heads. We have a file with a bunch of broken rocker shaft photos, due to the incorrect machining of the shaft mounting radius in the pedestals. That allows the shaft to rock in the saddle, causing the bolts to loosen. Only if this machining is corrected will we make geometry correction kits. This is not new, and has been known for years to be an issue.

If anyone has questions, after reading through our tech articles, feel free to call. I would be happy to provide an explanation to answer those questions.
Click to expand...
Thanks for joining the conversation. Very helpful that you check in on these threads when you can.
I was just about to add a comment on lash caps. I tried lash caps on mine before I found out about the correction kits you offer. I found the same problem you mention. The roller tip moved back toward the center of the valve tip but the sweep got stupid wide. In my case, lash caps were no better. A couple of correction kits are in my future.
 
1bad360duster said:
Thanks for the info! How do the promaxx and edelbrock castings stack up? I heard they should be very simpliar castings.
Click to expand...
They are better, but I've found that none of the "cheap" heads are really a bargain. Until you get everything right, with components you can trust, the end cost is very similar to more expensive heads. That being said, I understand budgets so you get the best you can afford. Sometimes that means taking more time and making the corrections as funds allow.
 
B3RE said:
They are better, but I've found that none of the "cheap" heads are really a bargain. Until you get everything right, with components you can trust, the end cost is very similar to more expensive heads. That being said, I understand budgets so you get the best you can afford. Sometimes that means taking more time and making the corrections as funds allow.
Click to expand...
Understood, I didn’t necessarily mean the components as I know these need to either be replaced or checked, verified etc. I only meant as far as the rocker stand machining/position compared to the issue you brought up about speedmasters. Thanks again
 
I'm running Comp Magnum rockers on the 360 in my 67 Barracuda. Overkill for my engine, but I had a set sitting around so decided to use them. They are probably 15 years old but have seen few miles.

100 miles after installing them and a pair of out-of-the box Indy LAX heads, the intake valve for the #7 cylinder stuck open. Piston bent the valve head, and the engine made all kinds of funny noises, but I drove it 2-3 miles home, and, amazingly, the piston was fine, as was the Comp rocker and, if I remember correctly, even the valve seat and the pushrod (might be wrong about the pushrod, though). Put a new valve in (honed the guide just a bit), and have had no trouble since. (And, of course, the Comp rockers weren't the problem.)

Arrow in the pic below points to the rocker for the stuck open valve.

IndyLA-Xhead.jpg
 
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About ten years now on my steel Comp Magnum rockers with LA Edelbrock heads.
 
Maybe try a good used set of factory adjustables?

I will be using these bushed units I had done at RAU. Just need to find a good small solid cam & lifters. Going in my w200.

@B3RE have you made correction kits for these style rockers?

EAAEF854-E0C8-4C76-A098-DB57EC456BBC.jpeg


F87FBDF9-5ABF-4694-93B4-3A7EF1A235A0.jpeg
 
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