what size pushrods?
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what size pushrods? ok, i just got a new block and heads on my car but didnt change out the rifters... i had about 90 k miles on it.. and i ran my tr230 for about 4k miles.. i heard a buddy say he was using 7.35 pushrods because of the springs .. and i just bought new pp5.3 with dounle springs, not sure what kind... should i change out the pushrods to lengthen the life of them so i dont have to take the heads off too soon??? thanks...dwayne
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From: Orange, TX
Dwayne (or Dewaine, or Duane, or Dwaine).....
I have a Comp adjustable pushrod length checker you can use to find out exactly what size you need. You'll need a dial indicator to measure the amount of preload. I don't like to lend out my precision tools like dial indicators., torque wrences, etc.
The stock lifters like a lot of preload but are pretty forgiving. You can do a search to see what most people recommend (about .050 or so, I think).
Springs don't have anything to do with pushrod length. Changes in valve length, rockers, cam base circle and head thickness can cause you to need a different length pushrod. An aftermarket cam typically has a smaller base circle, which requires a longer pushrod..... shaved heads require a shorter pushrod.... longer valves require a shorter pushrod.
Combining an aftermarket cam with shaved heads can cancel each other out so most of the heads/cam/stock rocker/stock lifter setups end up close to stock length or a tad shorter if you have a fair amount shaved off your heads.
My car ended up needing stock length 7.4's but my heads aren't shaved much at all. A bunch of cars use 7.35's. You need to do a quick check to be sure. Lemme know if you want to borrow the pushrod tool.
Scott.
I have a Comp adjustable pushrod length checker you can use to find out exactly what size you need. You'll need a dial indicator to measure the amount of preload. I don't like to lend out my precision tools like dial indicators., torque wrences, etc.
The stock lifters like a lot of preload but are pretty forgiving. You can do a search to see what most people recommend (about .050 or so, I think).
Springs don't have anything to do with pushrod length. Changes in valve length, rockers, cam base circle and head thickness can cause you to need a different length pushrod. An aftermarket cam typically has a smaller base circle, which requires a longer pushrod..... shaved heads require a shorter pushrod.... longer valves require a shorter pushrod.
Combining an aftermarket cam with shaved heads can cancel each other out so most of the heads/cam/stock rocker/stock lifter setups end up close to stock length or a tad shorter if you have a fair amount shaved off your heads.
My car ended up needing stock length 7.4's but my heads aren't shaved much at all. A bunch of cars use 7.35's. You need to do a quick check to be sure. Lemme know if you want to borrow the pushrod tool.
Scott.
Last edited by ScottyG; Feb 23, 2004 at 09:38 PM.
Im using comp Rs and to get the preload right im using 7.35s on intake and 7.325s on exhaust due to the fact the base circle on the exhaust is .027 larger than intake on my X1. This is so Ill have the same preload on all the lifters. Them Ill will shim in .005 increments til I get the desired pre load. Its not necassary to use different pushrods but a buddy had a half a set of 7.325s left over so it was a no brainer. I want mine set up perfect so I can crack your *** Dwayne and I wont have any worries about reving to 6800 all day long. YT problem now solved.
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Originally Posted by J2KSS
Im using comp Rs and to get the preload right im using 7.35s on intake and 7.325s on exhaust due to the fact the base circle on the exhaust is .027 larger than intake on my X1.
It SOUNDS like you know what your doing.... but I know better. Who did all that figurin' and decipherin' for you?
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scotty, thanks man, and i will prob borrow that so i dont have to replace the lifters any time soon, after i get done with this, i want to be done for a while... but whenever i get off this shut down, ill give ya a holla... but you gotta come out to the track with us, but you dont have to race... just to have a good time
jason: thanks for the info, i didnt know all that, but ill measure mine to see what i need.. but i doubt i need new ones, just want to make sure!!
"bla bla bla", my cars at backers as we speak, he wants me to try out the z pack stuff that came out this weekend, so ill see how those do, and i might just rev mine up a tad higher, i think my setup can handle it, i got to figure out my peak hp and where it is so i can stay in it while bustin that ***... j/k, hopefully i can get off work one fri, and tune it (right) and try out the stall for the best 60' (low 1.5's and 1.4's if i get some gears) but i want to go race but ill have to wait... but im lookin forward to racing with ya, but remember, when i beat ya, no hard feelings....
jason: thanks for the info, i didnt know all that, but ill measure mine to see what i need.. but i doubt i need new ones, just want to make sure!!
"bla bla bla", my cars at backers as we speak, he wants me to try out the z pack stuff that came out this weekend, so ill see how those do, and i might just rev mine up a tad higher, i think my setup can handle it, i got to figure out my peak hp and where it is so i can stay in it while bustin that ***... j/k, hopefully i can get off work one fri, and tune it (right) and try out the stall for the best 60' (low 1.5's and 1.4's if i get some gears) but i want to go race but ill have to wait... but im lookin forward to racing with ya, but remember, when i beat ya, no hard feelings....
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Jason, It's obvious that you can trust Gerald's opinion on about ANYTHING. He's a good guy to know.
Stroker??? Who me??
A bunch of y'all have caught up and passed me. I gotta do SOMETHING to get back to "big dog" status. You can bet on it that the first digit of the engine size will be a "4". You guys may whup up on me but I'm gonna make you earn it!
Stroker??? Who me??
A bunch of y'all have caught up and passed me. I gotta do SOMETHING to get back to "big dog" status. You can bet on it that the first digit of the engine size will be a "4". You guys may whup up on me but I'm gonna make you earn it!
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ha, keep tellin yourself that and you might convince yourself of it.. but deep down, you know ill beat ya!!, na, itll be a good run, i cant wait to see those tea's .. why dont you go after joey on motor?? my tranny should be done thurs... i have to work all day wed but i have to stop by and pick something up thurs... if you still have it... later
