ST2126LSR Lifter
also, we had inconsistencies when comparing the number of turns on the checker and the number of turns on preload, we saw a 3:00 difference on the same checker length.
6 rocker arms had 2:00 - 4:00 preload with 7.500 pushrods < we may get 7.490 tick performance pushrod to confirm that they all are at or less than 0.035 preload
2 rocker arm was at zero lash with 7.500 pushrods < I think we should order 7.535 instead of 7.525.
using 7.525 pushrods we got the following preload turns
2 exhaust 6:00 <14 turn and 1/16 using checker
intake 6:00 <14 turn and 1/8 using checker
4 exhaust 8:00 <14 turn and 1/16 using checker
intake 8:00
6 exhaust 6:00 <zero lash at 7.500
intake 8:00 < 14 turns using checker
8 exhaust 8:00
intake 6:00 <zero lash at 7.500
should we leave it at 6:00 and 8:00 or should we buy 7.490 to confirm zero lash and 7.535 for the 2 short ones?
Last edited by QTR FMS; Feb 14, 2022 at 01:53 PM.
If you are ordering singles, you could check that you have zero or less than zero preload and order as needed.
You want to get that zero lash number and add your desire preload.
You don't want tension from the Valve springs or pressure from the lifter loading the checker tool. It can effect the true measurment.
They tell you to shoot for .035 with a plus/minus of .010 . Some builders shoot for the high side of that. I dont the expansion rate of the various blocks but I have herd the aluminum motors grow substantionaly more than the Iron blocks.
Last edited by 1FastBrick; Feb 14, 2022 at 08:00 PM.
also, we had inconsistencies when comparing the number of turns on the checker and the number of turns on preload, we saw a 3:00 difference on the same checker length.
6 rocker arms had 2:00 - 4:00 preload with 7.500 pushrods < we may get 7.490 tick performance pushrod to confirm that they all are at or less than 0.035 preload
2 rocker arm was at zero lash with 7.500 pushrods < I think we should order 7.535 instead of 7.525.
using 7.525 pushrods we got the following preload turns
2 exhaust 6:00 <14 turn and 1/16 using checker
intake 6:00 <14 turn and 1/8 using checker
4 exhaust 8:00 <14 turn and 1/16 using checker
intake 8:00
6 exhaust 6:00 <zero lash at 7.500
intake 8:00 < 14 turns using checker
8 exhaust 8:00
intake 6:00 <zero lash at 7.500
should we leave it at 6:00 and 8:00 or should we buy 7.490 to confirm zero lash and 7.535 for the 2 short ones?
I very often will double check my measurements by adding my desired preload to the checker tool and verifying I get 1/2 turn. It is a great secondary check to prove your method is correct.
If they're all coming in at 6:00-8:00 range, I would run them.
If you are ordering singles, you could check that you have zero or less than zero preload and order as needed.
You want to get that zero lash number and add your desire preload.
You don't want tension from the Valve springs or pressure from the lifter loading the checker tool. It can effect the true measurment.
They tell you to shoot for .035 with a plus/minus of .010 . Some builders shoot for the high side of that. I dont the expansion rate of the various blocks but I have herd the aluminum motors grow substantionaly more than the Iron blocks.
Aluminum expands way faster than steel. Since the pushrods are steel and the block is aluminum, you will lose about .010 preload. Or gain .010 lash. Depending on your perspective.
If running an iron block, your cold preload and hot preload will generally be nearly identical.
Aluminum expands way faster than steel. Since the pushrods are steel and the block is aluminum, you will lose about .010 preload. Or gain .010 lash. Depending on your perspective.
If running an iron block, your cold preload and hot preload will generally be nearly identical.
IIRC I think Mr. Tony Mamo told me basically the same thing when I was setting up an engine with one of his top end packages.
The Best V8 Stories One Small Block at Time
we checked bank 1 and we had 1 at 11:00 and another at 9:00.
I think we need at least 3 pushrods 7.515 long.
if it's true that every 1/4 turn is 0.018 preload then we may need 9 pushrods shorter around 7.515 and I think cylinder #6 intake pushrod confirms that 0.025 shorter pushrods removed 6:00 or half a turn.
we will try to target between 4:00 and 6:00 preload.
the compression test drastically improved now its between 180-190, it was 75-110 when we first installed 7.550 pushrods not sure if that is the reason or if it was the new headgasket not sealing properly and required heat cycle
so we got XD-A pushrods and compared them to tick performance and to get the same length visually comp cam needed 0.032 more, which is the difference between gauge length and theoretical length I assume, but when we installed them on the same rocker arm comp cam still needed to be 0.02 longer to be at the same lash.
now we are confused where did this 0.02 come from, is it from the pushrod end ?? the difference is large between the two pushrods its around 0.052
with tick performance, we need 7.5258 and with comp cam XD-A we need 7.580, this caused another problem the pushrod we order is 7.320-7.560.






