Does my measured pushrod length check out?
Thread Starter
Teching In
Joined: Jan 2016
Posts: 15
Likes: 0
From: Fowlerville, MI
Does my measured pushrod length check out? I'm looking for opinions to make sure the length I'm getting makes sense.
Basics are 243 heads - no milling, TSP Torquer V2, stock rockers, .040" head gaskets, LS7 lifters.
I have the comp cams push rod checker and am following vettenuts' process here: http://www.corvetteforum.com/forums/...ow-to-use.html
When the length checker is at 7.200 (8 turns) I have a little vertical play.
I turn the checker another half to 8.5 (I have to remove it every time, I can't get my fingers in there) to 7.225 and there is no longer a "click" when I pull up and down, but it does allow side to side movement.
Assuming a .080-ish preload for LS7 lifters, I should be looking for 7.305 push rods. This seems too short. I thought TSP used a smaller base circle and I would need longer push rods, even if the cup on LS7 lifters are .050" taller.
Any idea what I could be doing wrong? or is this a reasonable length for the setup. I was really expecting something along the lines of 7.350.
Thanks for looking. I was going to give TSP a call in the morning to see what they recommend.
Basics are 243 heads - no milling, TSP Torquer V2, stock rockers, .040" head gaskets, LS7 lifters.
I have the comp cams push rod checker and am following vettenuts' process here: http://www.corvetteforum.com/forums/...ow-to-use.html
When the length checker is at 7.200 (8 turns) I have a little vertical play.
I turn the checker another half to 8.5 (I have to remove it every time, I can't get my fingers in there) to 7.225 and there is no longer a "click" when I pull up and down, but it does allow side to side movement.
Assuming a .080-ish preload for LS7 lifters, I should be looking for 7.305 push rods. This seems too short. I thought TSP used a smaller base circle and I would need longer push rods, even if the cup on LS7 lifters are .050" taller.
Any idea what I could be doing wrong? or is this a reasonable length for the setup. I was really expecting something along the lines of 7.350.
Thanks for looking. I was going to give TSP a call in the morning to see what they recommend.
Put tape around the checker. That ensures it doest spin when you take it out.
Also check int and exhaust from at least one piston on each side of the motor.
But that sounds too short.
Also check int and exhaust from at least one piston on each side of the motor.
But that sounds too short.
Thread Starter
Teching In
Joined: Jan 2016
Posts: 15
Likes: 0
From: Fowlerville, MI
I did forget to mention that I got the same results on both intake and exhaust for cylinder 1.
Thread Starter
Teching In
Joined: Jan 2016
Posts: 15
Likes: 0
From: Fowlerville, MI
Using the method to measure preload here: https://ls1tech.com/forums/generatio...l#post12529924
I get 10.5 quarter turns - 2.625 turns - about .1233" preload. I counted out the length checker 12 turns, so it should be 7.400" (stock length) and it's very close in length to the stock pushrod. I'm much more comfortable going with a 7.350 pushrod. I gotta find a set of calipers big enough to measure and check them both.
I get 10.5 quarter turns - 2.625 turns - about .1233" preload. I counted out the length checker 12 turns, so it should be 7.400" (stock length) and it's very close in length to the stock pushrod. I'm much more comfortable going with a 7.350 pushrod. I gotta find a set of calipers big enough to measure and check them both.
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
Teching In
Joined: Jan 2016
Posts: 15
Likes: 0
From: Fowlerville, MI
Got a caliper. Turns out the tool is .020" long.
I measured the pushrod I used to check preload and measured in at 7.397. So it makes sense if I went with a 7.350 pushrod, my preload would be .0733" which is in range for what I've seen for recommended preload - moreso then .1233".
I measured the pushrod I used to check preload and measured in at 7.397. So it makes sense if I went with a 7.350 pushrod, my preload would be .0733" which is in range for what I've seen for recommended preload - moreso then .1233".
Launching!
Joined: Apr 2015
Posts: 257
Likes: 1
Just to clear up the tape suggestions above - put a few wraps of Teflon tape on the threads of the pushrod checker. Tape on the threads make the checker a little more difficult to turn and measurements will be more accurate. Do use a caliper for accurate measurements. Once you have a caliper, you'll find hundreds of uses for it and wonder how you got along without one.