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Discussion Starter · #1 ·
I was chatting with a summit representative about these (pn. 17001-16) comp cams roller rocker arms for my SBC 350 that a lot of you already know about. Currently have roller tip rockers with my solid flat tappet cam but I'm having to adjust the valves somewhat frequently (pushrods are still spinning so the lifters are okay). I was told I need to run guide plates with these full rollers, but the heads I have on the motor have guide slots milled into them. Would it work to forego the use of guide plates and just use the slots milled in the heads? Also I heard something about shims being used with full roller rockers? Would I need shims or would I simply adjust the lash with the poly locks like I do now with the roller tips?
 

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You need one method, and only on method, for controlling the rocker alignment - slotted heads (stock), self aligning rockers, or guideplates. DO NOT use more than one. If your heads are stock heads designed for a 5/16" pushrod, then you do not need guide plates. Most all aftermarket heads will require either guideplates or self aligning rockers.
 

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If the cam was going flat I would have noticed it in 2500 miles wouldn't I? Not a sarcastic question I'm actually wondering
If your valve lash is actually changing, what else could it be other than wear somewhere in the valvetrain? A little work to inspect now could save getting metal through the entire engine. I had a custom cam grinder talk me out of a solid flat tappet because he claimed that good quality lifters are simply not available for solid flat tappet due to low demand.
 

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Discussion Starter · #7 ·
If your valve lash is actually changing, what else could it be other than wear somewhere in the valvetrain? A little work to inspect now could save getting metal through the entire engine. I had a custom cam grinder talk me out of a solid flat tappet because he claimed that good quality lifters are simply not available for solid flat tappet due to low demand.
I'll check when I have my intake off to fix an oil leak, but if the pushrods are still spinning doesn't that mean the cam and lifters are operating properly? I'm thinking that my roller tip rockers are wearing out.
 

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I'll check when I have my intake off to fix an oil leak, but if the pushrods are still spinning doesn't that mean the cam and lifters are operating properly? I'm thinking that my roller tip rockers are wearing out.
spin is good indication, but not proof. Depends on what is wearing right now, the cam or the lifter or both or neither. The bevel that makes them rotate is ground into the cam itself. I can imagine a scenario where the lifter could wear while rotating if the metal is softer than the cam. Of course you could be right about the rocker. But only one way to tell for sure.
 

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Discussion Starter · #10 ·
Couple things.
What rockers and how much is the lash changing? Is it increasing or decreasing?
I forget the part number, but they're summit house brand IIRC cast steel roller tip rockers. Lash is increasing :sweat: I don't usually check how much, just set it where it's supposed to be and put the covers back on. Now that I think about it, it could be my poly locks not holding tight enough because I didn't flatten the top of the studs.
 

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I forget the part number, but they're summit house brand IIRC cast steel roller tip rockers. Lash is increasing :sweat: I don't usually check how much, just set it where it's supposed to be and put the covers back on. Now that I think about it, it could be my poly locks not holding tight enough because I didn't flatten the top of the studs.
Summit roller tip rockers do not have polylocks. Are you talking about a full roller Summit house brand or just a roller tip stamped steel rocker?


Never mind... I found the cast steel Summit roller tip rockers with the polylocks.
 

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Mark them with a silver sharpie or something for that.

Stud girdles help hold everything in place if your valve covers have the room.

How much the lash is changing is a good clue to what's going on.

It's normal to see some lash change after break in but anything still loosening indicates an issue that needs addressing.
If it helps, I like to set the lash .003 looser and tighten the lock nut them tighten the poly to get the desired lash. It helps get the lock tighter.

Flat studs and flat locks really help hold things too.
 

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Yep, those are the ones that I found on second look.


I would go ahead and inspect all the lifters and if pattern on bottom is good after 2500 miles, then cam/lifters are successfully broken in and you shouldn't need to worry about them further with your mild application (other than using high ZDDP multiweight oil like Brad Penn 10w30). Only then would I blame the rockers and other things in the valvetrain for the extra clearance. Good luck and best wishes for a successful repair.
 

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Discussion Starter · #16 ·
I would go ahead and inspect all the lifters and if pattern on bottom is good after 2500 miles, then cam/lifters are successfully broken in and you shouldn't need to worry about them further with your mild application (other than using high ZDDP multiweight oil like Brad Penn 10w30). Only then would I blame the rockers and other things in the valvetrain for the extra clearance. Good luck and best wishes for a successful repair.
I have been using conventional Havoline 10W-30 will that be a problem? Also I broke it in on straight 30W diesel engine oil with STP additive
 

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I think it's probably just my locks coming loose or the rocker ball wearing out
Doubt the locks are coming loose unless you really boogered up the tightening of them. Did you keep the rocker balls with the original rocker? if not, then that's an issue that will result in a broken/ripped rocker. If you pull them out and see any 'blueing' where the ball rides on the rocker then put a fork in them - they're done.
 

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Discussion Starter · #18 ·
Doubt the locks are coming loose unless you really boogered up the tightening of them. Did you keep the rocker balls with the original rocker? if not, then that's an issue that will result in a broken/ripped rocker. If you pull them out and see any 'blueing' where the ball rides on the rocker then put a fork in them - they're done.
Rocker balls never went to different rockers, I never looked for bluing but I will over thanksgiving break when I tear off the intake and upper valvetrain. I did have a rocker almost fall off during breakin so maybe my tightening methods are bad. Also, put a fork in them?
 
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