Help with push rod size

You got me on the math! Finished that at about 10p... Yeah, i understood i would get a wipe pattern, thats not the problem. It did get narrower as i shimmed, which is good. Just wasnt sure if the wipe was good where it is. Its a little high. The rocker was sitting low which was causing a wide high wipe. I think this might be the problem with reground cams, the base circle is smaller which means the pushrod has to be longer to make up the difference.
 
The shims determine wipe pattern as you have discovered. Run the .060" shims on both intake and exhaust for best pattern and select pushrod length to give you preload of at least 1/2 turn, but no more than 1 1/2 turns. Forget what the book says, those are only guidelines for factory components. You won't be able to get it exact, so as long as you are in the ballpark on preload, don't worry about it.

From the bits and pieces I can glean out of the various above posts, I'd say you should be safe with a 7.300 pushrod.
 
Right on, that was the pushrod i ordered. Id seen similar things on the LSx forums. Seen a guy there that had a pattern more towards the exhaust side of the head, said he ran it like that without any guide wear.
 
goodpattern.jpg

I ended up using the .060" shims with the 7.30" pushrods and these are the patterns. A lot narrower, and closer to the center with 3/4 turn of preload passed zero lash.

goodpattern2.jpg

Funny thing though, one of the sixteen pushrods i got was shorter than the rest, and even had the same part number etched in to it. Good thing i had a v6!

rockers.jpg

These rockers do almost look too good to cover up.
 
Glad you figured it all out. People really struggle with the concept of how to set pedestal rockers. What you have there is about as close to perfect as you'll ever get. Good job.
 
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