Adam86

iTrader: (10)

About to do this and have a few questions...

1. I'm using the Trickflow checker and can't seem to find how to tell the length. Would it be alright to use a micrometer to check? I figure this would be more accurate than any other method anyway.

2. I have LS7 lifters. How do I figure out preload? Or adjust it? Didn't know this was an option and I don't quite understand it. Valvetrain math is over my head, I'll be the first to admit. But I have to figure it out quickly.

3. Will all of the pushrod lengths be roughly the same? Or do I need to check all 16 valves at TDC and measure each one?

Thanks!

mark21742

With your pushrod length checker you are looking for 0 lash....if you get say 7.320 at 0 lash and you need .080 preload you will want to get 7.400 pushrods. All of them " should" be roughly the same, but it doesn't hurt to check a few to be sure

99screamindemon

i would do 1 or 2 intake valves and the same exhaust just to be safe having said that i am about to do this as well from what i understand just make sure your lifter is on the base lobe of the cam than adjust your pr checker to 0 lash, than ad in your desired pre load to determine what length pr. someone correct me if i am wrong

R6cowboy

iTrader: (3)

ttt
I also need to learn how this is done, as I will be measuring for PR length here shortly.

theevette

iTrader: (2)

Does he need a solid lifter

99screamindemon

from what i understand no because i have lighter checking springs i am goin to use

Adam86

iTrader: (10)

The preload is what I'm really not getting here. What should I be shooting for and how do I measure and adjust it?

vettenuts

iTrader: (4)

Not sure on the Trickflow adjustable pushrod, but here is a link to using the Comp. Link

First you should figure out how much the length changes with each turn and what your starting length is then you can figure out how it is used.

Also, note that the measurements that are used by most pushrod vendors is gauge length. If you measure with a caliper from end to end then you will be measuring overall length as long as the adjustable pushrod has something on the end to flatten it like the hole in the pushrod. If you use calipers, then subtract 0.017" from the length you measure to get an approximate guage length.

Adam86

iTrader: (10)

Alright guess I'll have to figure out how to measure this checker or else just get a different one. So let me make sure I have this right...

1. Install stock pushrods in 2 valves of same cylinder.
2. Lightly tighten rocker bolts.
3. Get lifter in one valve at TDC (base circle of cam)
4. Take off rocker and pushrod, install length checker, and reinstall rocker
5. Adjust checker until there is no play in the rocker when the rocker is up all the way.
6. Check pushrod length.
7. Add desired preload (I'm shooting for .07" with my LS7 lifters) to pushrod length.
8. So that if my initial measurement was 7.38" on the checker, I would need 7.45" pushrods. 7.38+.07=7.45
9. Check other valve and perhaps another cylinder if desired.

Am I correct in my method of thinking here?

Adam86

iTrader: (10)

Anyone?

J1D2warrior

iTrader: (2)

When I do this I take a black marker and paint the tip of the valve black.

then I bolt down the rocker and spin the motor over several times by hand. If your length is correct the tip of the rocker will remove the marker in the CENTER of the valve.

vettenuts

iTrader: (4)

That will not work on an LS1 motor. That is a stud mounted method.

vettenuts

iTrader: (4)

Yes, that is basically correct or you can put cylinder #1 at TDC and check both valves at the same time which is easier.

J1D2warrior

iTrader: (2)

my apologies. I used that method on my LS2 but I also installed shaft mount adjustable rockers.

Adam86

iTrader: (10)

Thanks guys! I'll try it the way I listed and see what I come up with.

wildcamaro

iTrader: (15)

So you are measuring the pushrod checker's length after you found it and then add .070" ?

7.38 total length - .070 lifter preload = 7.31 (length of the pushrod checker after adjusted to make zero lash) ------>Am i correct in my assumption? Obviously i was using the example from above...

mark21742

Close, but you add the lifter preload to the length, not subtract it to get 7.48, or an even 7.4 pushrod.

Adam86

iTrader: (10)

So if I measure and get 7.44" with preload added in 7.45" pushrods should suffice correct? The preload amount should be flexible enough to make up for the hundredth of an inch.

vettenuts

iTrader: (4)

Two questions. How are you measuring the adjustable pushrod length? If you are using a caliper and measuring end to end then you need to correct for this depending on the pushrod vendor. Second, what lifters and what is the range of preload?

Adam86

iTrader: (10)

I ended up picking up a Comp Cams adjustable checker so I'll be using that.
I'm using LS7 lifters so I'm going for a preload of roughly .07"