Pushrod Length Help
Thread Starter
On The Tree
Joined: Jan 2013
Posts: 119
Likes: 0
From: Ohio
Pushrod Length Help I'm in the middle of an LS1 build.
I have AI ported 243s milled to stock specs.
A custom cam from FlowTech.
Stock head gaskets.
Morel 5206 lifters.
I am at the pushrod measuring stage, and I keep coming up with an average of 8.5 on my adjustable pushrod which, with lifter preload, only brings the rods I need to 7.3.
This seems short to me and Ed at FlowTech.
What am I doing wrong? I've measured a dozen times now on multiple cylinders.
I have AI ported 243s milled to stock specs.
A custom cam from FlowTech.
Stock head gaskets.
Morel 5206 lifters.
I am at the pushrod measuring stage, and I keep coming up with an average of 8.5 on my adjustable pushrod which, with lifter preload, only brings the rods I need to 7.3.
This seems short to me and Ed at FlowTech.
What am I doing wrong? I've measured a dozen times now on multiple cylinders.
There are a half dozen variables that affect the pushrod length you need - lifter plunger height, cam base circle diameter, deck height, installed spring height in your heads, compressed gasket thickness, etc. etc. It's possible that you're not doing anything wrong.
Not sure which Morels you are running, but when I installed mine I took several measurements of the lifter and found that they would require shorter pushrods. I found that the combination of taller lifter and shorter preload resulted in a difference of approximately 0.100" shorter pushrod requirement.
What is the preload you are using?
What is the preload you are using?
Thread Starter
On The Tree
Joined: Jan 2013
Posts: 119
Likes: 0
From: Ohio
I talked to Ed at Flowtech a bunch and we agreed it is what it is if that's what I'm measuring it at.
Thank you for your advice, everyone.
I went through the procedure of finding TDC a couple more times just to make sure I was and stuck two of the stock pushrods onto the lifters and watched them to make sure I was on the base circle of the cam. I came out with an average of 9 turns after that to 0 lash. I think I was being a bit lazy with my own thought of 0 lash before. 9 x 0.50 = .45 + 6.8 = 7.25 + .040 (mid range) = 7.29. 7.30 were the closest I could get and they are still within the preload range of the 5206s, so I'm happy with where I'm at.
I went with the 7.3s. Doing the first start tomorrow.
Last edited by Metallifan; Aug 18, 2014 at 11:54 PM.
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo Thread Starter
On The Tree
Joined: Jan 2013
Posts: 119
Likes: 0
From: Ohio