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Rocker Arm ??
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DRR Pro
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Rocker Arm ??

I have SBC Jesel Sportsman aluminum solid body 1.5 rockers with 500 runs 1/8 mile since new when I removed several years ago. The cam is 0.665” intake and 0.635” exhaust lashed. High rpm chip was set to 7500. When I removed and inspected rockers they looked good. The spare engine was rebuilt to short block and I’m going to have the top end put back on in summer.

My question is, At what point in 1/8 mile runs, would one send these rocker arms back in for service? I plan to run this engine to 1,000 runs after installed.

I’m also considering purchasing an LSM-100 valve spring checker. I have 600 runs on identical engine in car and plan to go to 1,000. The heads came with the valve spring set pressure recorded, so I know where they started at. If valves came set to 260# , when checking pressure, how low in pressure would be acceptable??
 
Posts: 2538 | Location: 53056 | Registered: December 30, 2009Reply With QuoteReport This Post
DRR Sportsman
Picture of BD104X
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I'm not an authority on rocker life (although I did have over 500 runs on an .800 lift big block Jesel set so I doubt your small block will have any issues) but you may want to get the LSM torque wrench adjusting tool as well... I'm told that when the rocker fails around the adjuster (which isn't uncommon) it's from overtightening the locknut which stresses the rocker body.


Billy Duhs - BD104X@gmail.com
 
Posts: 638 | Location: New Jersey | Registered: February 26, 2000Reply With QuoteReport This Post
DRR Top Comp
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quote:
Originally posted by markemark:
Rocker Arm ??

I have SBC Jesel Sportsman aluminum solid body 1.5 rockers with 500 runs 1/8 mile since new when I removed several years ago. The cam is 0.665” intake and 0.635” exhaust lashed. High rpm chip was set to 7500. When I removed and inspected rockers they looked good. The spare engine was rebuilt to short block and I’m going to have the top end put back on in summer.

My question is, At what point in 1/8 mile runs, would one send these rocker arms back in for service? I plan to run this engine to 1,000 runs after installed.

I’m also considering purchasing an LSM-100 valve spring checker. I have 600 runs on identical engine in car and plan to go to 1,000. The heads came with the valve spring set pressure recorded, so I know where they started at. If valves came set to 260# , when checking pressure, how low in pressure would be acceptable??


The main thing is when you use the LSM checker, make sure to get a good feel for it before coming to any conclusions.

Your camshaft guy knows more about the lobe intensity in play than I do. I'd be guessing.

Best thing to do if you do put new springs on it, is check em the next day after their first outing. Write that number down.

If you bought the camshaft used, there are ways to determine the intensity looking at the specifications - cam doctor. If you don't know who's it is.

The rocker arm question is a guessing game as well, without knowing a slew of possible variables.
 
Posts: 9398 | Location: Madeira Beach Fl. | Registered: June 12, 2018Reply With QuoteReport This Post
DRR S/Pro
Picture of Lenny5160
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A hard-earned word of warning: when using an on-head spring tester, don't pull the rocker too far which would allow the pushrod to come out of the cup on the rocker arm.


Tony Leonard
 
Posts: 3185 | Location: Inver Grove Heights, MN | Registered: March 18, 2004Reply With QuoteReport This Post
DRR S/Pro
Picture of banjo
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I have those rockers on my engine. Probably had excess of 1500 runs on them. I sent them in for a rebuild and they replaced all the bearing, 3 shafts and 2 adjusters. They said they were in really good shape. I sent them in because they had been on there for a long time. But there were no current issues.

Provided all your valvetrain geometry is correct, I think you would be fine to keep running them as you want. Just like anything else, things break for no apparent reason.I pay attention to valve lash changes and give them a visual inspection every so often.

Good luck


Bill Simpkins
74 Nova
SBC 406
3240 pounds
Speierracing heads

60 1.27 (10/16)
1/8 6.03@111 (10/16)
Best 9.87@131 on the rev limitor 1 Feb 2013


nova

quarterpanelview

wheelie

FTI Converter
www.speierracingheads.com

 
Posts: 1830 | Location: San Angelo | Registered: March 07, 2005Reply With QuoteReport This Post
DRR Trophy
Picture of Wildman
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Inspection of the rocker arm will tell you. As the axle and bearing wear it will get begin to get additional clearance. Wash the rockers in parts cleaner and inspect them. The sides of the body will start to wear on the stands. Check the roller tip, when they are starting to wear you will feel the clearance between the axle and roller. Check the cup on the adjuster and the ends of you push rods, if they are wearing you will see it. There are so many factors, it's hard to put an amount of run time before rebuild.
 
Posts: 111 | Location: at a dragstrip near you | Registered: April 02, 2006Reply With QuoteReport This Post
DRR Pro
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Great advice….Thanks everyone!!
 
Posts: 2538 | Location: 53056 | Registered: December 30, 2009Reply With QuoteReport This Post



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