Comp roller rockers and poly locks with no set screws. Can someone educate me on what determines if you run the set screws or not? TIA.

You run the locking set screw.

That is what I thought. Lol! But I don't claim to know everything (anything, actually) so when I went to check on a buddy who just pulled a head due to a blown head gasket I was surprised to see there were no set screws on any of the poly locks. Motors probably have 150 - 200 hours on them this way. Originally build by Baker and then rebuilt by a shop in MO that Myrick Coil recommended (can't think of it off the top of my head) so either Baker set it up this way originally or the second shop forgot to put them in. Heads are Dart Pro I's.

He musta had stud girdles and trusted them to hold the nuts or your mistaken on the poly locks with no set screw and they were crimp nuts. Without set screws those nuts would back off very quickly and beat valve train to death, Smitty

Smitty, it's never had stud girdles. They sure look like poly locks to me as you can see the threads on the inner part of the nut.

Not familiar with crimp nuts.

On another weird note, he thought all the poly lock nuts were ran all the way down tight. Again, I wasn't there so no idea why he thought that when he backed them off but that is what he said. Not sure how it would have survived with that much pre-load either if that is really how they were.

https://www.summitracing.com/parts/c...SABEgIh1vD_BwE

Not sure how they would not back off without the set screws

Agree. Hence my stupid question. I'm going to talk him into pulling another valve cover so I can see/snap a pic of how they are untouched. He just looked at me funny when I asked about the set screws. He said, "what set screws?"

Loc-Tite probably

Mystery solved. When he showed me the poly lock I didn't have my readers with me and when I asked about set screws and he said there were none I took his word and just snapped a quick pic. Had I looked more closely, even with my 60 year old eyes, I would have seen no daylight down the barrel of the nut and would have known something was in there. I had my buddy worried enough that he was about to call the builder and he decided to take one last look and sure enough, down in the nut the set screw was there (and there in all the other ones). He had never messed with an engine with roller rockers/poly locks before so he didn't know to look for the screws and just backed the nuts off. Now we know how the nuts never backed off.

Apologies for the wild goose chase!

Crimp nuts are Stover nuts.

The nut is deformed and pressed in slightly in 3 locations 120° apart. This puts tension on the threads as the nut expands as it's threaded onto the rocker stud etc.

Standard stock style rocker roc.