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Old 01-05-2017, 06:50 PM   #31
dre0396
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I had the same thing I bought the car that way. So I did
A cam and lifted set up in it.
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Old 01-05-2017, 07:43 PM   #32
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The LS9 cam has more lift than the LSA cam (0.558/0.562 vs 0.480/0.480). The stock LSA valve springs are only rated for 0.520 lift. If you're running the LS9 cam with LSA springs, chances are the springs are experiencing coil bind, which is never a good thing. All kinds of valvetrain ugly can occur. Take a close look at your keepers, retainers, and pushrods. the LS9 also has Ti valves and the LSA heads don't.
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Old 01-05-2017, 08:34 PM   #33
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I have LS9 heads and had the LS9 cam. The valves were floating above 5700. They are rated for .570 lift and had 800 miles on them. Did not so good things to my guides.

I think the oil pan is the only stock metal part on the engine now. I developed a tick also, cam, pushrods, rockers and lifters were perfect. My machine shop said they've had 4 sets of LS9 heads have wiped guides.
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Old 01-08-2017, 12:37 PM   #34
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Thumbs down

I checked everything on the top-end. It has the CompCams trunion upgrade too.

I did another test today, unplugging each coil one-by-one listening for a difference. I didn't catch this before. There's a faint, dull knock at idle, only after it's up to full temp. Unplugging most cylinders makes no difference in the noise, EXCEPT for #7. When I unplug #7's coil or injector, the knocking gets noticeably louder. Looks like something's wrong with the bottom-end.

I guess this in-turn is causing the low oil pressure condition (50 PSI cold start idle, 25 PSI hot idle) which allows the lifters to float and clack when it's revved. It was this lifter noise I would hear and thought was the problem.

I've experienced several spun rod bearings over the years. This one's different. All of the others would knock all the time, hot or cold. I expected a knocking noise would get fainter when disabling the cylinder, not louder.
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Old 01-08-2017, 12:48 PM   #35
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Could be the lack of anything pushing down on the piston. Whenever it's not firing, the crank is pulling down the rod in both strokes. Usually a slight blip of the throttle will give a quick double knock indicating slack being taken up in both directions by a rod bearing.
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Old 01-08-2017, 12:56 PM   #36
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i postulate it may have something to do with the piston, or perhaps a wrist pin.
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Old 01-08-2017, 01:08 PM   #37
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Yup, just listened to several youtube videos of LS rod knock. It's the same sound as many of them. I sure wish we could get the oil pan off without pulling the engine or dropping the subframe.
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Old 01-08-2017, 01:36 PM   #38
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It's better to start a teardown with it out of the car anyway, imho.
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Old 01-08-2017, 04:28 PM   #39
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Quote:
Originally Posted by Nothubertjfarnsworth...View Post
It's better to start a teardown with it out of the car anyway, imho.

Yes, absolutely agree with you. Just bitching because the APS kit makes R&R soooo much more difficult.
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Old 01-08-2017, 04:43 PM   #40
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How does the oil look?
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Old 01-08-2017, 10:13 PM   #41
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Amen gnx the kit is a pita to pull out. My engine is out when number 7 popped on me and I edit really look forward to putting it back in.
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Old 01-09-2017, 06:04 AM   #42
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Quote:
Originally Posted by Nothubertjfarnsworth...View Post
How does the oil look?

The oil is still new looking. But it's only been idled for a few minutes. The oil from when I drove it 50 or so miles with the noise was also visibly metal free. Every other time I've had rod knock, metal flake was obvious on the dipstick in bright sunlight. I'm thinking it's either not as bad, or it's something else like the piston or wrist pin as was mentioned.

I'm leaning towards stroking and forging now.
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Old 01-09-2017, 06:13 AM   #43
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Quote:
Originally Posted by socal gto...View Post
Amen gnx the kit is a pita to pull out. My engine is out when number 7 popped on me and I edit really look forward to putting it back in.

Any tips? ;-)

Bolt a board across the frame rails to keep the trans in-place when pulling the engine.

Remove the turbo centers from the exhaust and set aside before pulling the manifolds. Just seems easier.

The right side SS intake pipe is always a pain. The left side manifold and the steering rack. The battery ...ugh. LOL
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Old 01-09-2017, 07:20 AM   #44
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Quote:
Originally Posted by GNXClone...View Post
The oil is still new looking. But it's only been idled for a few minutes. The oil from when I drove it 50 or so miles with the noise was also visibly metal free. Every other time I've had rod knock, metal flake was obvious on the dipstick in bright sunlight. I'm thinking it's either not as bad, or it's something else like the piston or wrist pin as was mentioned.

I'm leaning towards stroking and forging now.

You could cut open the filter and peak around.
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Old 01-09-2017, 01:09 PM   #45
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4 + hours of Jaw boning!

Greetings Guys; I'll add a nickel's worth! A few years back I had an issue with heavy wear on the roller tips & valve stem tips (Gen I SBC, The Bronze Brick). And a good buddy had a lifter out of his Ls6 that looked very similar to the many I've seen that have destroyed rollers! So I wrote a letter to Comp Cams as I've been so happy in the past with their products & warranty service. To my surprise Rick Sparks the VP of the company gives me a phone call. Well as things turned out he was just a couple of years younger than me & we hit it off pretty well. This is what I learned from him after 6 phone calls & 4+ hours jaw boning. Loading of case hardened tool steel parts, ZDDP content in the oil & internal CLEANNESS. It seems that these modern roller cams actually load the lifter rollers (MUCH) more than the old solid lifter flat tappet cams of yesteryear! Hence if ya rev them up use some oil with additional ZDDP & if you have heaver valve springs than stock, same advice. Mobil 1 had higher levels of ZDDP back in 2004-06 when they specified it. And yes I know they still do, but what choice do they (GM) have. As no street oil has enough ZDDP protection now days. They just hope that ya don't rev it so much that it wears out before the warranty is up! Modest driving & stock springs will get ya by for 100,000 miles. And more than 1/2 of all failures occur with M1 oil. My buddies Ls-6 was modified by Lingenfelter & they recommended 15-50 M1, 22,000 miles later a junk cam & lifter roller. And maybe the most common mistake that us hot rod types make is contamination & synthetic oils for break in. They (Comp) found after 1000's of hours on their dyno's that ANY contamination will be death to a roller sometime in the future. Like 20,000 miles later! As the roller surface can be damaged by the smallest particles that aren't carried away by the oil. And Synthetics are TOO slippery to carry away contamination. So damage can be done during break in & not show up for many miles or years. As it's almost humanly impossible not to get some contaminants in the engine when ya open it up. So after engine surgery Rick recommended conventional break in oil for 20 minutes. Dump it & refill it again with break in oil for 500 miles. Then switch to some synthetic oil with additional ZDDP, they found that the Driven Ls-30 oil by Joe Gibbs was an outstanding choice. One can of worms, Ole' Bob.
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Old 01-10-2017, 04:18 PM   #46
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Quote:
Originally Posted by ForzaFTW...View Post
The LS9 cam has more lift than the LSA cam (0.558/0.562 vs 0.480/0.480). The stock LSA valve springs are only rated for 0.520 lift. If you're running the LS9 cam with LSA springs, chances are the springs are experiencing coil bind, which is never a good thing. All kinds of valvetrain ugly can occur. Take a close look at your keepers, retainers, and pushrods. the LS9 also has Ti valves and the LSA heads don't.

When I learned that LSA and LS9 springs are different, I replaced the springs with LS9 springs. That was about 35,000 miles ago.

Trunions are the upgraded ones from CompCams.

Pushrods are all straight (rolled on plate glass)

I think the problem is low oil pressure from too much clearance from a bottom end issue.
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Old 01-10-2017, 04:26 PM   #47
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When I unplug either the injector or the coil on #7, I can hear a dull knocking sound. None of the other cyls do that. Sounds sort of like rod knock, but not quite the same. I'll figure it out when I get the engine out.

I've decided to finally give up pushing OEM parts to their limits.

This forged short block from SDPC race shop is going in:

416ci
LS3/L92 6.2L Gen4 Aluminum Block
Wiseco -15cc Forged Pistons
Wiseco Ring Set for N2O, Boosted, or N/A
Callies Comp Star 4340 Crankshaft
Callies Comp Star H-Beam Connecting Rods
24x Reluctor Ring
Clevite H Series Rod & Main Bearings
Durabond Cam Bearings


Estimate around 10:1 compression with the LSA heads and LS9 gaskets.
I may have to lower the boost or timing a bit since I was at 9.5:1. Hoping the extra displacement will help make up for it.
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Old 01-10-2017, 04:34 PM   #48
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Quote:
Originally Posted by Silvah Goat...View Post
I have LS9 heads and had the LS9 cam. The valves were floating above 5700. They are rated for .570 lift and had 800 miles on them. Did not so good things to my guides.

My machine shop said they've had 4 sets of LS9 heads have wiped guides.

Wow, nice to know! I will have them checked out.

What did you do to fix the floating?
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Old 01-10-2017, 05:11 PM   #49
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Put in Manley dual springs. Got rid of the rest of the stock GM parts in the motor.
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Old 01-11-2017, 01:27 PM   #50
GNXClone
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Quote:
Originally Posted by Silvah Goat...View Post
Put in Manley dual springs. Got rid of the rest of the stock GM parts in the motor.

Thank you for the info. This part# by chance?

Manley 221436-16
Polished NexTek H.P. Valve Springs GM LS-series

I currently have LS9 springs I bought from Lingenfelter 3-1/2 years ago, for $70. Apparently they don't carry them anymore.
L230045297 - GM LS9 Valve Springs Matched Sets

Now they sell these for $350!
Competition Cams Dual Valve Springs LS9 ZR1
Part Number: CC26926-16


Just spent some time perusing the CTS-V forums. Apparently the preferred spring for some when running the LS9 cam in the LSA is PAC 1218.

Last edited by GNXClone; 01-11-2017 at 02:55 PM.
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