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Discussion Starter · #1 ·
My 69 SS has a 454 bored to a 468 and it appears the rockers are original and not replaced when the engine was rebuilt by the previous owner. They continue to click after 3 adjustments. Is there any advantage to roller tip or roller rockers, stock heads, radical cam, great power. Stock valve covers. Or just go with stock ones.
 

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1970 El Camino SS396, VortecPro 467, ATI TH400, Moser 12 bolt /TruTrac 3:42, Hedman headers
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Roller rockers are questionable on mild street style engines, with lifts less than 0.600”,IMO, many will disagree but gains in power are questionable. Smokey Yunick used to say oil temp went down about 15 degrees with roller rockers, nothing about power increases. Never saw a magazine article the showed less than 10-15 hp or more..but when you’ve rented a dyno to write an article you best show results OR ELSE. Very few people who have had their wallet thinned by the purchase will admit they saw much gain but they make a hellava good bragging point, etc. In a mild motor this money would best spent elsewhere. The GM sp/hi/perf. rockers stamped with an “H” are an excellent choice, but pricey, forum members also speak highly of the long slot “Summit” or Crane, etc. long slot style rocker. Your engine, your money, your choice.
 

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Maybe change the rocker nuts. SOMETIMES they can back off. We built a boat engine and it was making noise. Turned out the replacement nuts were not crimped tight and holding.
 
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Roller rockers are questionable on mild street style engines, with lifts less than 0.600”,IMO, many will disagree but gains in power are questionable. Smokey Yunick used to say oil temp went down about 15 degrees with roller rockers, nothing about power increases. Never saw a magazine article the showed less than 10-15 hp or more..but when you’ve rented a dyno to write an article you best show results OR ELSE. Very few people who have had their wallet thinned by the purchase will admit they saw much gain but they make a hellava good bragging point, etc. In a mild motor this money would best spent elsewhere. The GM sp/hi/perf. rockers stamped with an “H” are an excellent choice, but pricey, forum members also speak highly of the long slot “Summit” or Crane, etc. long slot style rocker. Your engine, your money, your choice.
Good advice. I use the "long-slot" GM rockers. They used them on L88 and LS6 500+ hp engines.
I would keep the cam lift around .550" max; they say they are ok to .600"
 

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1st off have you inspected those rocker arms for wear and tear ? Are the rocker stud threads ruined from overuse ? but if everything looks OK then try this.If your cam has over .500 lift then you need the long slot rocker arms.
Get a bottle of engine assembly lube then get some of that red stuff underneath the rocker arm balls. Re-adjust the rockers by the EOIC method making sure you have good lubrication on the rockers at startup.Then run it and take note of how long it runs without making any noise.
You might want to try this, it's a mod I read about on the performance forum.Vortecpro uses a nut without a crimp that fits the rocker arm stud threads.(I forget the size off hand)Then uses that nut to make his adjustment and locks that nut with the stock crimped rocker nut.It makes adjustments more precise and they hold the adjustment longer.
I hope I repeated this rocker nut mod correctly I couldn't find that original post.
 

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1970 El Camino SS396, VortecPro 467, ATI TH400, Moser 12 bolt /TruTrac 3:42, Hedman headers
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I believe a 7/16 fine threaded nut under the factory adjusting nut if I remember correctly.
 

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Roller tips I am not sure are worth much. Full Roller Rockers are worth it IMO. I have never seen a dyno result that didn't show an increase in power from roller rockers. I think much of the gain comes from the fact stamped rockers are not always a very accurate ratio.
 

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I cant imagine rockers being the cause of the noise unless the nuts and pivot balls are messed up; how much noise is there? Some cams are loud by nature.
 

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I agree with what Gene said. It is pretty rare for rocker arms themselves to be the source of a noise unless they are actually loosening up. Make sure that is really the problem before wasting money on parts that you dont need.
 

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My 69 SS has a 454 bored to a 468 and it appears the rockers are original and not replaced when the engine was rebuilt by the previous owner. They continue to click after 3 adjustments. Is there any advantage to roller tip or roller rockers, stock heads, radical cam, great power. Stock valve covers. Or just go with stock ones.
Other than making your valve spring float earlier and a lighter wallet, no. If some rockers keep bleeding down seems like you have a few lifters that are not holding pressure very well. Is this a solid or hyd cam?
 

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Discussion Starter · #12 ·
Hyd cam with a 600+lift. . . . .I have not done anything to the engine since I got the car 15 years ago. Rebuilt the suspension back to original, Carb, alt, dist, added PS, brakes, exhaust, radiator, headers, clutch, plugs and wires. PO said the engine was built 2k miles ago and that is all he said. An Ebay car. Great suggestions and I will re check the rockers and if need be replace with long slot OEM. Pulled each plug while running, no difference.
 

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66 El Camino 57 Chevy pickup 2004 Tahoe
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adjust the valves carefully using the EOIC method. Do you know what this means?
 
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Make sure mechanically the valve train is ok meaning retainer to seal, coil bind, rocker slot length adequate, piston to valve, retainer to rocker arm, push rod geometry, rocker to valve cover, and valve adjustment of course
 
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And you can do BOTH the above in one procedure if you dont mind taking your time. I did every year to check the springs in the 427, as it saw prodigious rpms. Anyway, as you do the " Just Opening, and Just Closing" on each set of valves you can visually inspect them to ensure they are running true.

Let us know if you find anything. I'm out of expertise as I have not run stamped arms since the 70's, yet I'm thinking in the past I;ve had to pull all the rockers to check pivot balls before as well, and found some galled ones to replace. ( which caused me to double nut that solid LT1 mechanical cam - although the dumb kid was likely floating the valves)

We seemed to have ALOT more valve spring issues back in the day.

SO MAYBE the rockers could be causing some noise IF one or more of the pivot ball isnt right, OR if they are binding anywhere as mentioned above.

My only issue is the utter precision of setting solid lash , as opposed to the " sort of close - until you cant spin the pushrod, hydraulics. But that's everyone, and you'd certainly notice a loose arm when you go thru the EO/IC procedure.
 

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Roller tips I am not sure are worth much. Full Roller Rockers are worth it IMO. I have never seen a dyno result that didn't show an increase in power from roller rockers. I think much of the gain comes from the fact stamped rockers are not always a very accurate ratio.
The only thing I hate about Roller rockers on a BBC is if your springs are right on the edge pressure wise the roller rockers cam make the engine go into valve float much sooner. Had that happen on two engine and Super Chevy proved that out on a 502 one time also.
 

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The only thing I hate about Roller rockers on a BBC is if your springs are right on the edge pressure wise the roller rockers cam make the engine go into valve float much sooner. Had that happen on two engine and Super Chevy proved that out on a 502 one time also.
I've never heard of this. I assume the roller rockers are a bit heavier on the nose than stamped steal. I wonder if certain rockers are better than others in terms of different design and different materials.
 

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I've never heard of this. I assume the roller rockers are a bit heavier on the nose than stamped steal. I wonder if certain rockers are better than others in terms of different design and different materials.
From what I have been told it's the extra weight on the tip compared to a stamped rocker that causes the problem at higher rpm. Think of it this way, if you ran a rocker with lets say 75 grams on the tip and then change to a rocker that has 150 grams on the tip multiply that by the max rpm of the cam and you will get the picture how much more there is on the spring. Nothing wrong with using roller rockers just make sure you use good springs. Anything you can do to keep the valvetrain light will generate more rpm before the engine may go into valve float.
 

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The only thing I hate about Roller rockers on a BBC is if your springs are right on the edge pressure wise the roller rockers cam make the engine go into valve float much sooner. Had that happen on two engine and Super Chevy proved that out on a 502 one time also.
Thats because the zz502 has marginal springs maybe so they stamped steel rockers will survive?
 
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