243 heads, Tsp 224r cam, ls7 lifters
#41
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Originally Posted by 01ssreda4
NO!!!!! It equals around 80, not 47.
Originally Posted by tech@WS6store
^ you quoted this in 2010...from shane at thunder
. 1 full turn wtih a stock 8mm X 1.25 bolt is ~.047" preload as measured at the pushrod/rocker interface.
. 1 full turn wtih a stock 8mm X 1.25 bolt is ~.047" preload as measured at the pushrod/rocker interface.
0.047" is the pitch of the rocker bolt rotation. It is NOT the preload equivalent. And actuality the pitch is more like 0.049, since it's a 1.25mm pitch.
But it's a lever with the fulcrum over the valve. Assuming a 1.7 rocker ratio, you gotta go times 2.7 divided by 1.7 and you get 0.078". All that stuff where 1.25 rotations to 060 preload include the bolt torque to 22 ft lbs. once you start torquing the bolt, you stop preloading the lifter. Cause the lifter is tight against the head.
OP, you measured 7.325 to zero lash, add your preload to that measurement and you're good. 7.4 will be fine. Even if you ran 7.425, they wouldn't be so long as to hold your valves open. Using bolt rotations to measure preload is not a great idea. Using it to verify preload is a good disaster check.
From zero lash and 0.070 preload, it'll take right at 1 rotation to take up the preload and another half rotation to torque the bolt, so you'll be close to 1.5 rotations.
Hope that helps
#42
Looks like i am going for longer pushrod a performance engine builder(mostly works on LS engines here looked my car and he said "you need 7.440 lenght pushrods your pushrod are short it cause valve train noise.I hope thats the solution
#43
https://www.youtube.com/watch?v=Bai1...ature=youtu.be
This is the video after lifter cam head swap not running the car like 1 week waiting for correct pushrods.does that the right sound for short pushrods ?
Regards
This is the video after lifter cam head swap not running the car like 1 week waiting for correct pushrods.does that the right sound for short pushrods ?
Regards
#45
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It sounds like lifter noise, yes.
Is it from pushrod length? or oil pressure? or any other kinds of valve train noises?
There is not a replacement for measuring your pushrods. TSP could likely tell you "on stock heads, stock lifters, stock gaskets 7.xxx usually works". But an educated guess (granted a WELL -educated guess) all it is. If you're not sure, and you guess wrong again, you'll be thinking "well, I've tried two different pushrod lengths, so THAT's not it..."
I do understand not wanting to do it. It's annoying and delays reassembly, but it is an important step int he process.
Is it from pushrod length? or oil pressure? or any other kinds of valve train noises?
There is not a replacement for measuring your pushrods. TSP could likely tell you "on stock heads, stock lifters, stock gaskets 7.xxx usually works". But an educated guess (granted a WELL -educated guess) all it is. If you're not sure, and you guess wrong again, you'll be thinking "well, I've tried two different pushrod lengths, so THAT's not it..."
I do understand not wanting to do it. It's annoying and delays reassembly, but it is an important step int he process.
#46
It sounds like lifter noise, yes.
Is it from pushrod length? or oil pressure? or any other kinds of valve train noises?
There is not a replacement for measuring your pushrods. TSP could likely tell you "on stock heads, stock lifters, stock gaskets 7.xxx usually works". But an educated guess (granted a WELL -educated guess) all it is. If you're not sure, and you guess wrong again, you'll be thinking "well, I've tried two different pushrod lengths, so THAT's not it..."
I do understand not wanting to do it. It's annoying and delays reassembly, but it is an important step int he process.
Is it from pushrod length? or oil pressure? or any other kinds of valve train noises?
There is not a replacement for measuring your pushrods. TSP could likely tell you "on stock heads, stock lifters, stock gaskets 7.xxx usually works". But an educated guess (granted a WELL -educated guess) all it is. If you're not sure, and you guess wrong again, you'll be thinking "well, I've tried two different pushrod lengths, so THAT's not it..."
I do understand not wanting to do it. It's annoying and delays reassembly, but it is an important step int he process.
#47
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Thanks Darth_V8r like i said in my previous post i thought i need shorter pushrod but i went wrong i towed the car to a engine builder mostly works on LS engines he measured and said "you are really low on preload this cause valve train noise and he said i need 7.440 and luckly i found 7.440 pushrod hope those come in 1-2 day