can anyone help asap.
Thread Starter
Pro
Joined: Jun 2013
Posts: 700
Likes: 0
From: Knox TN
can anyone help asap.
LS6 01 z06 changed cam and springs 238/242 .615 / 610 113+2 and BTR springs.
measured a bit ago with pushrod length checker.
one cylinder was 8 3/4 turns for zero lash
one liked 9 turns for zero lash
one liked 10 1/4 for zero lash
Now i am puzzed why the varience in my measurements..
I come up with lengths at zero lash of 7.275
7.25
7.325
these were all done with each cylinder at TDC....needing help assap as the store with the pushrods closes at 3PM. EST.
measured a bit ago with pushrod length checker.
one cylinder was 8 3/4 turns for zero lash
one liked 9 turns for zero lash
one liked 10 1/4 for zero lash
Now i am puzzed why the varience in my measurements..
I come up with lengths at zero lash of 7.275
7.25
7.325
these were all done with each cylinder at TDC....needing help assap as the store with the pushrods closes at 3PM. EST.
Thread Starter
Pro
Joined: Jun 2013
Posts: 700
Likes: 0
From: Knox TN
Ok I think I am maybe on to something. Im not sure if I measured cylinder 1 at TDC compression or exhaust stroke...How can I figure that out? So I would measure cylinder one and six at TDC...but how do I know which is a compression and which is at exhaust stroke or does this matter when measuring the pushrod length?
Drifting
Joined: Jul 2009
Posts: 1,382
Likes: 37
From: Everett WA
St. Jude Donor '14
When you are on the compression stroke on #1, both valves will be closed. You should be able to rotate the engine a few degrees in either direction and there should be no lift at all. For me this is how I know I am on the "back" of the cam lobe.
Drifting
Joined: Jul 2009
Posts: 1,382
Likes: 37
From: Everett WA
St. Jude Donor '14
To be very basic....I always adjusted the rockers before manifold install so I can watch the lifters. On the compression stroke as the piston comes up both valves should be closed (both lifters will be down). If the exhaust valve (lifter is moving up) is open as the piston goes up then you are on the exhause stroke and soon after the piston reaches the top then the intake will open as the piston goes down and should be closed before the piston starts to travel up again for the compression stroke.
Drifting
Joined: Jul 2009
Posts: 1,382
Likes: 37
From: Everett WA
St. Jude Donor '14
Ok I think I am maybe on to something. Im not sure if I measured cylinder 1 at TDC compression or exhaust stroke...How can I figure that out? So I would measure cylinder one and six at TDC...but how do I know which is a compression and which is at exhaust stroke or does this matter when measuring the pushrod length?
http://ls1tech.com/forums/generation...od-length.html
Thread Starter
Pro
Joined: Jun 2013
Posts: 700
Likes: 0
From: Knox TN
yeah i got it sorted out...just went by this instead:
Quote:
Originally Posted by Joseph
LSX Firing Order 1, 8, 7, 2, 6, 5, 4, 3
TDC Cyl. #1) Camshaft dot at 12:00 / Crankshaft dot at 12:00
TDC Cyl. #8) Camshaft dot at 1:30 / Crankshaft dot at 3:00
TDC Cyl. #7) Camshaft dot at 3:00 / Crankshaft dot at 6:00
TDC Cyl. #2) Camshaft dot at 4:30 / Crankshaft dot at 9:00
TDC Cyl. #6) Camshaft dot at 6:00 / Crankshaft dot at 12:00
TDC Cyl. #5) Camshaft dot at 7:30 / Crankshaft dot at 3:00
TDC Cyl. #4) Camshaft dot at 9:00 / Crankshaft dot at 6:00
TDC Cyl. #3) Camshaft dot at 10:30 / Crankshaft dot at 9:00
Quote:
Originally Posted by Joseph
LSX Firing Order 1, 8, 7, 2, 6, 5, 4, 3
TDC Cyl. #1) Camshaft dot at 12:00 / Crankshaft dot at 12:00
TDC Cyl. #8) Camshaft dot at 1:30 / Crankshaft dot at 3:00
TDC Cyl. #7) Camshaft dot at 3:00 / Crankshaft dot at 6:00
TDC Cyl. #2) Camshaft dot at 4:30 / Crankshaft dot at 9:00
TDC Cyl. #6) Camshaft dot at 6:00 / Crankshaft dot at 12:00
TDC Cyl. #5) Camshaft dot at 7:30 / Crankshaft dot at 3:00
TDC Cyl. #4) Camshaft dot at 9:00 / Crankshaft dot at 6:00
TDC Cyl. #3) Camshaft dot at 10:30 / Crankshaft dot at 9:00
Drifting
Joined: Oct 2006
Posts: 1,724
Likes: 23
From: Minnesota
I agree... if the rockers are on and adjusted. If you are only checking for pushrod length and no rockers are installed then there will be air no matter what because the valves will be closed no matter what.
To be very basic....I always adjusted the rockers before manifold install so I can watch the lifters. On the compression stroke as the piston comes up both valves should be closed (both lifters will be down). If the exhaust valve (lifter is moving up) is open as the piston goes up then you are on the exhause stroke and soon after the piston reaches the top then the intake will open as the piston goes down and should be closed before the piston starts to travel up again for the compression stroke.
To be very basic....I always adjusted the rockers before manifold install so I can watch the lifters. On the compression stroke as the piston comes up both valves should be closed (both lifters will be down). If the exhaust valve (lifter is moving up) is open as the piston goes up then you are on the exhause stroke and soon after the piston reaches the top then the intake will open as the piston goes down and should be closed before the piston starts to travel up again for the compression stroke.
Last edited by reactor2; Apr 26, 2014 at 07:16 PM.
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Drifting
Joined: Oct 2006
Posts: 1,724
Likes: 23
From: Minnesota
LS6 01 z06 changed cam and springs 238/242 .615 / 610 113+2 and BTR springs.
measured a bit ago with pushrod length checker.
one cylinder was 8 3/4 turns for zero lash
one liked 9 turns for zero lash
one liked 10 1/4 for zero lash
Now i am puzzed why the varience in my measurements..
I come up with lengths at zero lash of 7.275
7.25
7.325
these were all done with each cylinder at TDC....needing help assap as the store with the pushrods closes at 3PM. EST.
measured a bit ago with pushrod length checker.
one cylinder was 8 3/4 turns for zero lash
one liked 9 turns for zero lash
one liked 10 1/4 for zero lash
Now i am puzzed why the varience in my measurements..
I come up with lengths at zero lash of 7.275
7.25
7.325
these were all done with each cylinder at TDC....needing help assap as the store with the pushrods closes at 3PM. EST.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
If you actually are on the base circle and you are getting variations in push-rod length, there could be a few things that can cause it.
1. the rocker pedestal can be worn.
2. The rocker trunnion is worn.
3, The lifter internals are worn
Ive seen all three cause issues.
Bill
1. the rocker pedestal can be worn.
2. The rocker trunnion is worn.
3, The lifter internals are worn
Ive seen all three cause issues.
Bill