need some help...checking pushrods LS6
need some help...checking pushrods LS6 Ok so last night I got my BTR valve springs done...now I am about to measure for my pushrod length so maybe I can pick them up before the store closes.
I saw videos of people doing a marker method, but I have read that cant be dont on LS motors.
On my LS6 I need to measure. I understand getting a cylinder at TDC etc, what I dont get is how do I know what preload I want? I see other threads where people find their length and then add a preload. How do you find your preload? I am using stock LS6 rockers that are in my 243 heads.
I saw videos of people doing a marker method, but I have read that cant be dont on LS motors.
On my LS6 I need to measure. I understand getting a cylinder at TDC etc, what I dont get is how do I know what preload I want? I see other threads where people find their length and then add a preload. How do you find your preload? I am using stock LS6 rockers that are in my 243 heads.
If not - look here: https://ls1tech.com/forums/15457558-post1.html
AND
"If you are not familiar with the EO/IC method for determining valve events in a 4 stroke engine, its very simple:
For a given cylinder as the Exhaust valve is Opening, the intake lifter will be on the base circle of the cam and lash/preload should be checked for that intake valve.
For a given cylinder as the Intake valve is Closing, the exhaust lifter will be on the base circle of the cam and lash/preload should be checked for that exhaust valve."
--------------------------------------------------------------------------------
Yes I have the comp 7702. I am turning it out 10 turns so 7.3. Have cylinder one at tdc. Put the pushrod in adjusted to 7.3. Snug my rocker and just barely over hand right with socket. Then lift the rocker tip up and down. At 7.3 there is no play whatsoever. Even at 9 turns there is no up and down play. So now I am kind of confused. This is new cam. Comp 238/242 615/610 113+2 and btr springs.
Double check your work - make sure the TDC that your at is on the compression stroke, or use the EO/IC method above. Also make sure that during the measurement step the rocker is actually snug. It sounds like the rocker is less than snug when you are taking the measurement, but snug when you do the check.
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?
Pouria Savadkouei
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine
Verdad Gallardo
7 Most Reliable High-Performance Engines GM Has Ever Built
Verdad Gallardo
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin
Verdad Gallardo
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 There can be some differences between valves, but that is okay with hydraulic lifters.
The lengths you are coming up with seem short, but that could be attributable to the base circle change with the cam.
The lengths you are coming up with seem short, but that could be attributable to the base circle change with the cam.
You want pushrods that are 0.050 inch longer than the shortest measured length. That will give you at least 0.50 inch preload everywhere with a little more on some valves. You need not measure every valve.
From Service Manual
Rotate the crankshaft until the number one piston is at top dead center (TDC) of the compression stroke. In this position, cylinder number one rocker arms will be off lobe lift, and the crankshaft sprocket key will be at the 1:30 position. The engine firing order is 1,8,7,2,6,5,4,3. Cylinders 1,3,5, and 7 are left bank. Cylinders 2,4,6, and 8 are right bank.
With the engine in the number one firing position, tighten the following valve rocker arm bolts:
•Tighten the exhaust valve rocker arm bolts 1,2,7, and 8 to 30 Nm (22 ft. lbs.).
•Tighten the intake valve rocker arm bolts 1,3,4, and 5 to 30 Nm (22 ft. lbs.).
Rotate the crankshaft 360 degrees .
Tighten the following valve rocker arm bolts:
•Tighten the exhaust valve rocker arm bolts 3,4,5, and 6 to 30 Nm (22 ft. lbs.).
•Tighten the intake valve rocker arm bolts 2,6,7, and 8 to 30 Nm (22 ft. lbs.).
Install the valve rocker arm covers.
Rotate the crankshaft until the number one piston is at top dead center (TDC) of the compression stroke. In this position, cylinder number one rocker arms will be off lobe lift, and the crankshaft sprocket key will be at the 1:30 position. The engine firing order is 1,8,7,2,6,5,4,3. Cylinders 1,3,5, and 7 are left bank. Cylinders 2,4,6, and 8 are right bank.
With the engine in the number one firing position, tighten the following valve rocker arm bolts:
•Tighten the exhaust valve rocker arm bolts 1,2,7, and 8 to 30 Nm (22 ft. lbs.).
•Tighten the intake valve rocker arm bolts 1,3,4, and 5 to 30 Nm (22 ft. lbs.).
Rotate the crankshaft 360 degrees .
Tighten the following valve rocker arm bolts:
•Tighten the exhaust valve rocker arm bolts 3,4,5, and 6 to 30 Nm (22 ft. lbs.).
•Tighten the intake valve rocker arm bolts 2,6,7, and 8 to 30 Nm (22 ft. lbs.).
Install the valve rocker arm covers.