lifter advice with h/c swap
02-09-2008, 08:19 PM
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lifter advice with h/c swap i have looked through countless threads via the search on this but i have not found the answer to my question. I got heads and a cam from a buddy for cheap that had 3k on them ( he got a crate motor)and i know it ran well on his car(hotcam setup and p&p built 241 heads)... however after all of the research and seeing the parts he had for me.. i am confused 
. he had chromemoly pushrods he gave me with them which are 7.350 length but from what i read, stock length should be used (7.40) with this type of a setup for proper preload unless the head was milled or a smaller headgasket was used. i dont think he had a thinner gasket but not sure if he had the head milled.. i guess my question is - if the heads arnt milled and the oem style gasket is used would the 7.350 pr's still perform properly? i am also wanting to replace the lifters while the heads are off and am concerned about getting a lifter that accually has a shorter overall length (built in preload ect that needs longer pr's) im seeing that even though the ls7 lifter is the replacement for the ls1 stock lifter it suposedly causes slightly shorter length. what do you guys suggest? the car has 65k on it- should i stay with the stockers if they arnt worn badly or just go stock ls7's or would there be better lifters for this setup considering the info ive given? 
. he had chromemoly pushrods he gave me with them which are 7.350 length but from what i read, stock length should be used (7.40) with this type of a setup for proper preload unless the head was milled or a smaller headgasket was used. i dont think he had a thinner gasket but not sure if he had the head milled.. i guess my question is - if the heads arnt milled and the oem style gasket is used would the 7.350 pr's still perform properly? i am also wanting to replace the lifters while the heads are off and am concerned about getting a lifter that accually has a shorter overall length (built in preload ect that needs longer pr's) im seeing that even though the ls7 lifter is the replacement for the ls1 stock lifter it suposedly causes slightly shorter length. what do you guys suggest? the car has 65k on it- should i stay with the stockers if they arnt worn badly or just go stock ls7's or would there be better lifters for this setup considering the info ive given? 
02-10-2008, 07:55 AM
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IMHO, since they are going to be accessible, I would replace them. LS7 lifters should suit you just fine.
If you have doubts on the correct PR length, the correct way is to measure. A PR length checker can be had for $20 and is available from many sponsors.
Get more info on this set up from your friend. He should be able to confirm the gasket he was running and if the heads had been milled.
In the end...me.... I would measure for correct PR length.
R/
Frat
If you have doubts on the correct PR length, the correct way is to measure. A PR length checker can be had for $20 and is available from many sponsors.
Get more info on this set up from your friend. He should be able to confirm the gasket he was running and if the heads had been milled.
In the end...me.... I would measure for correct PR length.
R/
Frat
02-13-2008, 10:42 PM
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I agree with you on the measuring.. I guess the main question i am asking is.. if everything is a stock setup and a hotcam is installed, would 7.350 pr's work correctly or would i run into problems? if so what issues would it cause? Oh and i did go with the ls7 lifters.
02-28-2008, 12:18 PM
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With those short pushrods you are losing a minumum of .050 of preload which is way too much preload to lose.
I would suggest that while the heads are off you install a new set of LS7 or Morel lifters, put the heads back on and use the pushrod checker tool to measure the exact length pushrod you need. That way you will have a properly setup valvetrain and wont have to rely on internet guesswork.
I would suggest that while the heads are off you install a new set of LS7 or Morel lifters, put the heads back on and use the pushrod checker tool to measure the exact length pushrod you need. That way you will have a properly setup valvetrain and wont have to rely on internet guesswork.