moneypit94

New fti (comp) cam, a set of stock heads I sent to tea, trick flow large bore multilayer head gaskets, and comp cam truion kit.

Used a comp cam 6.800 adjustable push rod. Was exactly 11 turns for intake and just under 11 1/8 turns for exhaust for 0 lash.

Does 7.425 sound right? Was expecting to maybe go shorter and not longer.

dw456post

Isn't the comp pushrod checker .050 per turn? 11 x .050 =.550 + 6.80= 7.35
Add the 1/8th turn is .006, so = 7.356 is what I get.
And add in the preload of .050 and I get a 7.406----looks like you used .069 preload, which I'm sure is OK.

Atomic

iTrader: (37)

1 turn is 0.050", right?

Intake: 6.8+11*.05=7.35 then 0.050" preload for 7.4
Exhaust: 6.8 +11.125*.05=7.356 + 0.05" = 7.406

Obviously adjust if you want something different than 0.050" preload.

moneypit94

I did .070 for preload. That's what I kept reading was proper preload for ls2?

moneypit94

If .070 is not the recommended preload for the ls2 motor please let me know.

MuhThugga

Instead of counting turns, just buy 8" digital calipers and measure the length of the checker.

As for preload, .070" - .080" should be the goal with factory lifters.

slow trap

iTrader: (22)

the comp cams usually have a smaller base circle so slightly longer p-rods are required. not enough preload and you have that sewing machine sound. unfortunately alittle to long and valves may hang open or a collapsed lifter. the 7.425 should be perfect imo.

Gray86hatch

iTrader: (83)

Measure the actual length. Counting turns is asking for problems.

Tim

moneypit94

I have a seen a few people on here saying to actually measure the pushrod or pushrod checker. Unless you are using a specially designed tool to measure pushrods that will not be accurate. Pushrod length is not based off the end of one side to the end of the other. I have heard you can get away with that by subtracting .025 and be fairly close, but that becomes a guessing game.

gagliano7

I measured an old 7.4 pushrod so I would know how much the actual length is. Then I did the same with the checker to get my numbers. If I remember correctly the 7.4 came out to 7.418.

sabersaw30

iTrader: (10)

My valvetrain liked less preload on the ls7 lifters 10.5 turns on pushrod checker put me at 7.375 with .050 preload.Anything over .070 and mine was real noisy. I think the ls7 lifters like lower preload then higher.