Alright, here is a video of me preforming the length adjustment, go ahead and tell me where I am doing it wrong

https://www.dropbox.com/s/1u6puyujxe...Small.mp4?dl=0

I had to refresh after the upload to get it to start

 

No, the cam bearings cam out with uneven wear, as is normal with these engines, but did not indicate it had been rebored, or aligned honed. Machinist reinstalled new OE spec bearings.
I cant speak if the head had been previously milled, but my machinist did take .007" off. It did not appear the the engine had previously been torn down, but you can never be sure.
Is there some spot on the head that a measurement can be made to determine how much it has been milled?

 

The reason i purchased the calibrated length checker, is because I do not have a caliper or venier that will accurately measure over 6".

 

 

Screw your adjustable pushrod in. Snug rocker are down. Unscrew your adjustable checker until you get zero lash. Remove rocker, pull adjustable checker out and measure the length. Add .075" for preload. Done

 

I went out and bought an 8" vernier caliper to try to get to the bottom of my issues once and for all.
Its a $30 one from harbor freight, so not high quality, but should be good enough to verify my prior measurements with the comp cam checker.

I have a bunch of interesting measurements, if anyone is interested in cyphering them with the previous posts.
The comp cam adjuster fully closed should be 6.800 inches, but measured 6.814, .014 too long
The comp cam adjusted opened 10 turns should be 7.300", but I measured 7.307", .007 too long
I measured a new stock unused OE melling #MPR-614 pushrod at 7.381". I think the proper measurement for a 7.400 pushrod is 7.394, so this was .013 short, but I never had them in this motor
I measured the original pushrod out of this motor at 7.394"

The original lifters that came out of this motor:
over all length=2.608
distance down to retaining clip=.117
diameter of retaining clip=.038
distance down to lifter cup (.117+.038)=.155
distance lifter cup above cam (2.608-.155)=2.453"

The first set of replacement lifters I put in this motor
over all length=2.595
distance down to retaining clip=.070
diameter of retaining clip=.033
distance down to lifter cup(.070+.033)=.103
distance lifter cup above cam (2.595-.103)=2.492" (.039" higher than the lifters that came out)

the newest set of lifters I am putting in this motor, that I have been preforming push rod measurments with
over all length=2.599
distance down to clip=.077
diameter of retainign clip=.035
distance down to lifter cup=.112
distance lifter cup above cam (2.599-.112)=2.487 (.034" higher than the lifters that came out)

Then I went back and adjusted my comp cam length adjusted to zero lash,at 9 turns out, and measured it at 7.264". adding .060 preload, I end up with 7.324"
I ordered 7.325 one piece pushrods

FWIW. If I stuck a 7.400 pushrod on this lifter, I would be at .136 preload, and I think max is around .120, so I would bottom the lifter out, and I did see the valve start to open
Although it was done with the first set of replacement lifters, I think they were very close to bottom, and not pumping oil up to the rockers.
Hopefully these new pushrods will allow me to oil the rockers.
I can't speak of why my pushrods needed are so short at 7.30 I had been asking for or 7.325 I ordered. I understand that this is a full 10th of an inch below stock 7.400,
and very hard to account a reason for. Maybe the block had been previously decked, and heads milled, plus .007 I had milled,
and valve job probably recessed the valve another .002.

 

OK, you are measuring Overall Length with the caliper which is an end to end measurement. The adjustable pushrod measures gauge length, which is a point on the ball end that is 0.140" in diameter. Typically, this is around 0.014"-0.018" shorter than overall length but it is the most accurate measurement because it is where the ball end will ride on the lifter and the rocker. However, the adjustable pushrod is not the most accurate method due to the estimating of partial turns.

The valves will open when you tighten the pushrod until the lifter bleeds down. The LS7 lifters are a one for one replacement of the LS1 lifter.

See post #1 of this Link noting that Eric D is a retired GM engineer. I wouldn't get hung up on measuring lifters. I would get your zero lash number accurately and once you have that the rest is downhill from there.

 

How did all of this turn out?

 

I measured pushrod length on both the even and odd banks, and continually came up with needing 7.30" pushrods. I ordered the shortest that WS6 store had at 7.325", and replaced lifters and one piece pushrods. Also upgrade rockers. Back together and on the road, running great. Just driving back and forth to work, hoping to get past 200miles, where the 7.4" pushrods started coming apart.
I also noticed that it started right up, as opposed to before with the 7.4 pushrods, it refused to start until ether was added.
I posted about vacuum leak, that I found-previously when it refuse to start, and I pulled the intake muffler off to spray ether into the intake, I laid the muffler over onto a pulley, that wore a groove into the square part of the muffler, and creating a vacuum opening- fixed pretty easy with JB weld.
Think I finally got this one licked- thanks all
Brian