Another pushrod question
Thread Starter
Melting Slicks
Joined: Jun 2007
Posts: 2,704
Likes: 4
From: Lone Star State
Another pushrod question
I have an 02 Z06 with stock heads. My cam is 235/240, .649/.608, 11 LSA. I have the PRC dual springs rated at .660 lift.
With that being said, I was told by a vendor that I needed 7.4" chromoly pushrods. I know I should have measured, but didnt, because I didnt know.
Would 7.425" pushrods quiet down the valvetrain or would it be too much? I have the rockers torqued to 22 ft/lb. All of them will have a little play in them when assembled. This has me thinking maybe the so called "recommended" pushrods are not the correct length.
Please leave feedback if its going to be helpful, none of the "shouldve checked the pushrod length before ordering". Dint know then....
Anyways, I have seen where they have pushrod checkers, etc. Just want to get opinions to where I may not have to go through all of trouble. I know I should do it, just wanted opinions. Thanks.
With that being said, I was told by a vendor that I needed 7.4" chromoly pushrods. I know I should have measured, but didnt, because I didnt know.
Would 7.425" pushrods quiet down the valvetrain or would it be too much? I have the rockers torqued to 22 ft/lb. All of them will have a little play in them when assembled. This has me thinking maybe the so called "recommended" pushrods are not the correct length.
Please leave feedback if its going to be helpful, none of the "shouldve checked the pushrod length before ordering". Dint know then....
Anyways, I have seen where they have pushrod checkers, etc. Just want to get opinions to where I may not have to go through all of trouble. I know I should do it, just wanted opinions. Thanks.
Instructor
Joined: Nov 2006
Posts: 223
Likes: 0
From: Uncasville CT
I would think a cam with that much lift is ground on a smaller base circle which would require longer pushrods. If the pushrod length were correct there should be no play in the pushrods when the rockers are torqued. If the pushrods had play I would think you need a longer pushrod than 7.425. .025" would probably just take up the play. Then you need to add something for preload. Best bet is to get a checker for $20 and then contact a vendor you trust to size the pushrods with the correct amount of preload.
I'm sure much more knowledgable people than me will provide advice.
I'm sure much more knowledgable people than me will provide advice.
Instructor
Joined: Feb 2007
Posts: 122
Likes: 0
From: Charleston SC
I have a 231/234 duration with .643" and .598" lift respectively. I use comp cams hi tech pushrods at the stock length 7.4. I've had the cam installed for about 2000 miles now with no problems. I thought with the big lift it might sound like a sewing machine but not any more then the stock ls6 cam did. The springs I have are the Patriot Dual extremes.
Tech Contributor
Joined: May 2008
Posts: 2,843
Likes: 16
From: Howell Michigan
St. Jude Donor '09-'10-'11
Former Vendor
Joined: Feb 2007
Posts: 17,337
Likes: 39
From: Birmingham, AL www.hinsonsupercars.com 205-909-9402
Most people go with 7.400" Pushrods and they work just fine. Only way to tell for sure is to measure.
Comp Cams Pushrod Length Checker $19.99
Seth
Comp Cams Pushrod Length Checker $19.99
Seth
