blakern

iTrader: (9)

hey guys im trying to figure out pushrod length. I have a stock short block, texas speed PRC LS6 stage 1 heads, comp xer273 cam, stock rockers, texas speed dual springs, LS7 lifters, and stock type head gaskets (steel style). I used a push rod lenght checker and got 7.275-7.3125 to take the play out of the valve train, then add .060 preload right?? So that around 7.335-7.3725. ??? Anyone got any input?

jsmechanical

Do your measurements again and be careful not to preload the lifters at all (they are very easy to compress) while adjusting the length checker. The 37.5 thou variance in your measurements is quite a difference when it comes to lifter preload, that's 3/4 turn of a pushrod length checker.

On my setup I came up with 7.3125 to take up the slack and want to run 60 thou preload so I ordered 7.375 pushrods from Comp. A lot of manufacturers only make their pushrods in 50 thou increments so 7.375 can be harder to source than 7.350 or 7.400.

blakern

iTrader: (9)

Yeah I think the 7.335 size is the most accurate. I'll check again today before I order. If thats right the closest size would be 7.350, which should give me .075 of lifter preload.

But it kindof makes sence cause my new LS7 lifters are .050 taller than the stock ones right? and the stock pushrod lenght is 7.400. So if you take the stock pushrod lenght (7.4) minus the difference in lifter hight (.050) equals (7.350)

I think??

01ssreda4

iTrader: (96)

Yes the LS7 lifter is .050 taller on the cup surface.

Sales2@Texas-speed

iTrader: (5)

Agreed, re-measure and see what you've got. My guess is that 7.350" will do the trick and get you right around that .050" preload, which will be great for those lifters! Be sure to check intake and exhaust of course....it is possible to need 8 of one length and 8 of another!