Z28Venom

iTrader: (13)

TR230 Cam
5.7L LS1 Heads milled .022 w/ 2.02/1.60 SS Valves..

Right now I'm running 7.4"... My valvetrain is really noisy.. (sewing machine) would the shorter rods quiet this down any?

foff667

iTrader: (2)

probably...i think most go to the shorter PR's once you get the heads milled .020.

Z28Venom

iTrader: (13)

Thanks...

ROGERSPERF.

Any time you mill heads or have a block decked or a valve job done you need to recheck your push rod and rocker are geomitry. Just because your buddy or some one told you he is using this lengith push rod dose not me it will fit yours unless it is a combination that has been worked out by the same engine builder doing the same thing on your engine.This is the biggest reason for VALVE TRAIN FAILEUR.





mike

Scalpel

iTrader: (4)

Most Comp Cam grinds you buy (the 12 I have measured for the LS1 were all this way) from the vendors have a base circle 0.030" smaller than stock. You're heads are milled 0.022", that's only 0.008" difference, so 7.400" will work just fine.

This calculator will give you the pushrod length by a calculation based on your heads being milled and cam base circle, etc.
Here ya' go: http://home.insightbb.com/~l.proctor1/p-rod.xls
Enjoy!
This assumes stock spring installed height for an LS1. The stock pushrod size is base on an LS1 stock pushrod.

However, the only real way to tell is to check your preload, etc.

ROGERSPERF.

Thats my point you must check the pre load on the lifter.





mike

Scalpel

iTrader: (4)

I agree, do it correctly the first time!

Deeavi

iTrader: (16)

I don't know if you guys remember the post on lifter preload with adjustable rocker arms. Crane says 2 full turns. I adjusted mine that way and the engine runs great no lifter noise to speak of, but with non adjustable I think the setting is .020" to .060". Correct me if I am wrong! But I think 2 turns on the adjusting nut is more than .060". There seems to be allot of variation in the way people set the LS engine valve train.

offaxis

iTrader: (19)

You should run the stock length pushrod. If your heads are milled more than .30 then you would use the shorter pushrods. Atleast that is what thunder told me when i bought that cam.

Z28Venom

iTrader: (13)

Thanks.. I'll go with a set of the Hardened 7.4" Rod from Thunder...

Deeavi

iTrader: (16)

You can buy a set of Trickflow Chrome Molly thickwall pushrods from Summit for $84.50 These are better than the ones from Thunder. These are equal to the comp cams Hi Tech Push Rods. I have used them in several engines, incuding my LS1