I just finished my valve spring/roller rocker swap, and wondered if there was anything special that I needed ot do to break them in properly. I used CC Pro-magnum NSA 1.6 RR's and GM LT4 springs and guideplates with new hardened pushrods, retainers and locks. I just cranked the engine, and it seems to be running smoothly, but I did not rev it very high. I used Shoebox's install guide (many thanks) and went ~1/6 turn past zero lash, which was fairly easy with the poly locks built into the pro-mags. It did not sound like any of the valves were too loose at idle.

Just wanted to make sure that I wasn't going to break anything. Thanks.

 

Youre going to want to heat cycle your springs a few times before they see very many rpm's. I just ran mine til it got up to operating temp, turned it off with the electric waterpump and fans running and it cooled right down. Did that 2 more times and then drove it around fairly gingerly for a few miles. After that, I started beating on it and havent stopped since. Other than that, there is no real break-in period.

 

A half dozen or so heat/cool cycles should get you on your way.

 

I thought you are supposed to go 1/2 turn past zero lash with 3/8 stud,
and a little less with 7/16 stud. Is 1/6 enough?

 

Thanks for the replies.

I did get 7/16 studs, and I had read reccomendations for between 1/8 turn and 1/4 turn, so I split the difference and used 1/6th turn because it was easier to see visually.

 

To my knowledge, the studs have nothing to do with the "turn past" zero lash. With my comp R lifters, I usually run them at a 1/8th turn...if that. With stock lifters, youre normally better off going 1/4 turn...sometimes a little more depending on the condition of the lifters.

 

Sure the studs have something to do with the amount past zero lash. 3/8 studs have 24 threads per inch and 7/16 studs have 20. You will go more distance with one turn on a 7/16 stud.

 

I did not know that. I stand corrected. Guess I need to do a lil more work on my knowledge.