silverZ98

iTrader: (6)

hey guys thanks for looking i have done a search on this and thought id post this to see what you guys think and if im in the right ball park of finding my push rod length. as i been told i came up with too short of a reading

frost i set the timing marks at 12 o'clock to get the lifters on the base cr for number 1 cylinder then i took my comp cams push rod checker and turned it out 10 turns for a 7.3 length installed it and snugged down the rocker arm and watched it push in the push rod checker so i knew that wasn't zero lash. so i took everything back out turned in the checker half a turn witch should be 7.275. reinstalled it and the rocker and it got me zero lash. no up and down movement in rocker and the checker did have no preload on lifter here. so i then added .050 for the preload and came up with 7.325. So im asking what you guys think?

lifters im using are gm ls7's heads are 5.3s milled to 61cc,

djfury05

iTrader: (30)

Sound right in the ball park to me.. The ls7 lifters have a lifter cup that sits higher than ls1's, you have milled heads and probably a thin gasket so I don't see why they can't be as short as you measured

janaka

iTrader: (7)

hell i'm at 7.3 with 59cc 5.3 heads (TSP) and LS7 lifters

gokussx4

iTrader: (3)

I am looking for a good measuring guide as well. Where did you get the part on adding
.050 for the preload?

If you don't have timing marks what else is a good way to make sure your lifter is riding on the base cr?

Thanks!

vettenuts

iTrader: (4)

Pull driver's valve cover, rotate motor with plugs out until intake valve just closes. TDC is about 1/2 turn more (actually a little less). Rotate and use a straw or flashlight to check for piston reaching top of cylinder.

silverZ98

iTrader: (6)

thanks guys for the input. i just wanted to see what others thought as i checked my measuring 4 or 5 times to make sure. but then was told by a few that it sound to short. the 7.325 are ordered and if i need to go longer i will but for now thats what the motor will have on its first start up after it gets back in car.

silverZ98

iTrader: (6)

was told after you have zero lash to add .050 to .075 for the preload

silverZ98

iTrader: (6)

yea man i remember being told that the ls7 lifters set about .050 higher than the old style lifters. looks like i did everything right. need my clutch to come in new push rods to come in get the rockers on, and clutch then the motor can go back in car. and hope it starts lol