pushrod question.....
04-09-2009, 09:16 PM
#1
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pushrod question..... ok guys i need your opinions....
i recently got a custom specd cam 227/231 614/617 112+2 it was supposed to be installed with TSP 5.3 heads. well things came up and i didn't get my heads so i am stuck with stock 241's. 7.45" pushrods were recomended with the cam....
my car seems to be almost slower than it was with just boltons and there is alot more valvetrain noise!!!!!
my question is.... Do you think these pushrods are to long? I have a dynotune monday and im afraid the pushrods are to long..... or do you think it just needs a tune really bad?
how do i know if the pushrods are the right length?
i recently got a custom specd cam 227/231 614/617 112+2 it was supposed to be installed with TSP 5.3 heads. well things came up and i didn't get my heads so i am stuck with stock 241's. 7.45" pushrods were recomended with the cam....
my car seems to be almost slower than it was with just boltons and there is alot more valvetrain noise!!!!!
my question is.... Do you think these pushrods are to long? I have a dynotune monday and im afraid the pushrods are to long..... or do you think it just needs a tune really bad?
how do i know if the pushrods are the right length?
04-09-2009, 10:05 PM
#3
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I need to do that tommarow incase i need to cancell my tune.... If my pushrods are a little to long i assume that would kill my power...
04-09-2009, 11:18 PM
#6
"You need to pop a valve cover and check the wipe pattern on top of the valve. The wear mark should be centered. If it isn't then you need to get a pushrod length checker and then get new pushrods."
On the LS1, the pushrod determines preload on the lifters, not whether the rocker is centered over the valve. So you will need a pushrod length checker but to see if your preload is correct. I assume stock lifters? If so the preload needs to be between .060 and .120. To change if the rocker is centered over the valve you may need shims under the rocker. And a tune is definitely in order to make the most of your purchase.
On the LS1, the pushrod determines preload on the lifters, not whether the rocker is centered over the valve. So you will need a pushrod length checker but to see if your preload is correct. I assume stock lifters? If so the preload needs to be between .060 and .120. To change if the rocker is centered over the valve you may need shims under the rocker. And a tune is definitely in order to make the most of your purchase.
04-10-2009, 07:37 AM
#7
"You need to pop a valve cover and check the wipe pattern on top of the valve. The wear mark should be centered. If it isn't then you need to get a pushrod length checker and then get new pushrods."
On the LS1, the pushrod determines preload on the lifters, not whether the rocker is centered over the valve. So you will need a pushrod length checker but to see if your preload is correct. I assume stock lifters? If so the preload needs to be between .060 and .120. To change if the rocker is centered over the valve you may need shims under the rocker. And a tune is definitely in order to make the most of your purchase.
On the LS1, the pushrod determines preload on the lifters, not whether the rocker is centered over the valve. So you will need a pushrod length checker but to see if your preload is correct. I assume stock lifters? If so the preload needs to be between .060 and .120. To change if the rocker is centered over the valve you may need shims under the rocker. And a tune is definitely in order to make the most of your purchase.
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04-10-2009, 10:02 AM
#8
"You need to pop a valve cover and check the wipe pattern on top of the valve. The wear mark should be centered. If it isn't then you need to get a pushrod length checker and then get new pushrods."
On the LS1, the pushrod determines preload on the lifters, not whether the rocker is centered over the valve. So you will need a pushrod length checker but to see if your preload is correct. I assume stock lifters? If so the preload needs to be between .060 and .120. To change if the rocker is centered over the valve you may need shims under the rocker. And a tune is definitely in order to make the most of your purchase.
On the LS1, the pushrod determines preload on the lifters, not whether the rocker is centered over the valve. So you will need a pushrod length checker but to see if your preload is correct. I assume stock lifters? If so the preload needs to be between .060 and .120. To change if the rocker is centered over the valve you may need shims under the rocker. And a tune is definitely in order to make the most of your purchase.
04-10-2009, 11:11 AM
#11
"You need to pop a valve cover and check the wipe pattern on top of the valve. The wear mark should be centered. If it isn't then you need to get a pushrod length checker and then get new pushrods."
On the LS1, the pushrod determines preload on the lifters, not whether the rocker is centered over the valve. So you will need a pushrod length checker but to see if your preload is correct. I assume stock lifters? If so the preload needs to be between .060 and .120. To change if the rocker is centered over the valve you may need shims under the rocker. And a tune is definitely in order to make the most of your purchase.
On the LS1, the pushrod determines preload on the lifters, not whether the rocker is centered over the valve. So you will need a pushrod length checker but to see if your preload is correct. I assume stock lifters? If so the preload needs to be between .060 and .120. To change if the rocker is centered over the valve you may need shims under the rocker. And a tune is definitely in order to make the most of your purchase.
04-10-2009, 05:26 PM
#13
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just got done pulling a valve cover and i think my pushrods are to long.....
i colored the top of the valve stem and put the rocker back on.... here is a picture of the wear pattern....
i colored the top of the valve stem and put the rocker back on.... here is a picture of the wear pattern....
04-10-2009, 10:28 PM
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im going to put in one of my stock pushrods and see how that works.... if its correct ill order some new 7.4 rods! If not ill order a pushrod checker....
04-10-2009, 10:52 PM
#15
The misinformation in this post is ......well .... PR length does not affect wipe pattern. However pr length can affect power by improper preload. Stock length should be very close to optimum preload but it is ALWAYS best to measure. Your new cam will have a slightly smaller base circle but stock length will prolly work just fine or go up to 7.425
Last edited by SOMbitch; 04-10-2009 at 10:57 PM.
04-11-2009, 05:22 AM
#16
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Sometimes i wonder why poeple ask a question if they allready think they know the answer.
You need to determine p-rod length? Easy, use a p-rod checker, adjust to 0 lash, read measurement, add preload value and voila > your p-rod length needed.
Stock heads and valves, stock gasket and non adjustable stock rockers, your wipe pattern will remain unchanged from stock.
You need to determine p-rod length? Easy, use a p-rod checker, adjust to 0 lash, read measurement, add preload value and voila > your p-rod length needed.
Stock heads and valves, stock gasket and non adjustable stock rockers, your wipe pattern will remain unchanged from stock.
04-11-2009, 07:36 AM
#17
Pushrod length wont change wipe pattern because the tip of the valve and the trunion on the rocker are points that are set (non adjustable). So that makes the pusrod cups placement non adjustable also, which makes the pushrod only preload the lifter more or less.
You must measure for pushrod length, anything else is a guess.
04-11-2009, 07:57 AM
#18
I ask myself this daily, that or they dont know but want a certain answer to make them feel better and argue when they dont get it.
Pushrod length wont change wipe pattern because the tip of the valve and the trunion on the rocker are points that are set (non adjustable). So that makes the pusrod cups placement non adjustable also, which makes the pushrod only preload the lifter more or less.
You must measure for pushrod length, anything else is a guess.
Pushrod length wont change wipe pattern because the tip of the valve and the trunion on the rocker are points that are set (non adjustable). So that makes the pusrod cups placement non adjustable also, which makes the pushrod only preload the lifter more or less.
You must measure for pushrod length, anything else is a guess.
We all have something to learn. I guess some people are not as good at learning as you....
04-12-2009, 11:28 PM
#19
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when the pushrod is at the bottom of its stroke i can wiggle it back a forth a little ( as light pressure on valve/spring.... is this correct?
04-13-2009, 06:54 AM
#20
I sorta almost agree. Stock heads, rockers won't change the wipe pattern as it came from the factory. However, a larger lift cam will change it because the rocker has to rotate through a larger angle. So the wipe should be checked with any aftermarket cam prior to measuring for pushrods. Pushrods should be the last part ordered for any installation. I kind of wish the vendors would include an adjustable pushrod with their kits and then ship the pushrods separately once the owner has measured.