why do cammed LS1s always tick?
Thread Starter
Melting Slicks
Joined: May 2005
Posts: 3,394
Likes: 12
From: Leon Iowa
St. Jude Donor '06-'07-'08-'09
Mine is just the XE lobe, not the XER. I bought a Comp pushrod checker and from what I could tell I needed the 7.4 pushrods. There is a guy on LS1tech that has my exact came cam i have and he runs the 7.425 so I guess I don't know.
Melting Slicks
Joined: Jul 2002
Posts: 2,722
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From: DFW Texas
CI 7-8 Veteran
CI 8 Car Show Winner
St. Jude Donor '07
G5X4 cam (24x/24x XE-R lobes on a 111 lsa), PRC dual springs, 7.425" pushrods.
Stock heads, lifters, rockers, etc. (for a limited time
).
Engine is very quiet, no ticking. Inside the car with radio off, if you focus really hard, you can detect a faint "sewing machine" sound...but it certainly isn't obvious or noticible.
I was actually surprised at how quiet it was when I first drove it after the cam swap.
Of course I can never be content, so the car is in the process of being torn down again to flycut the pistons, and put on some stage 2 TEA 5.3 heads, GMPP "caddy" lifters, ARP studs, .040" Cometics, and probably some adjustable roller rockers.
Stock heads, lifters, rockers, etc. (for a limited time
).Engine is very quiet, no ticking. Inside the car with radio off, if you focus really hard, you can detect a faint "sewing machine" sound...but it certainly isn't obvious or noticible.
I was actually surprised at how quiet it was when I first drove it after the cam swap.
Of course I can never be content, so the car is in the process of being torn down again to flycut the pistons, and put on some stage 2 TEA 5.3 heads, GMPP "caddy" lifters, ARP studs, .040" Cometics, and probably some adjustable roller rockers.
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
How did you measure and what did you come up with for number of turns on the checker?
Thread Starter
Melting Slicks
Joined: May 2005
Posts: 3,394
Likes: 12
From: Leon Iowa
St. Jude Donor '06-'07-'08-'09
Le Mans Master
Joined: Jun 2004
Posts: 6,269
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From: Dallas Texas
St. Jude Donor '06-'07-'09-'10
You young Guys amuse me worrying about valve clicking noise. Obviously, you never heard an old Musclecar or early Vette with a solid lifter cam. There was no way to quiet them and the that sound was a badge of a hot engine. 
Pro
Joined: Oct 2002
Posts: 586
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From: Idabel OK
Pro
Joined: Jul 2000
Posts: 590
Likes: 1
From: Suffolk New York
Absolutely, we hear the valves closing more because we removed stock exhaust manifolds which tended to dampen out those sounds.
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Drifting
Joined: Oct 2004
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From: Mesa Arizona
.
Thread Starter
Melting Slicks
Joined: May 2005
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From: Leon Iowa
St. Jude Donor '06-'07-'08-'09
I did find out that the cam i have has a base circle raduis of .732 and the diamater is 1.463 . I was told on ls1 tech that I needed the 7.425. How did they calculate that?
Team Owner
Joined: Mar 1999
Posts: 22,025
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From: At the beach in little Rhody
Not sure what the stock base circle is, although I still have EG's stock cam in the other room and can measure it. But basically, your lifter now sits a little lower in the lifter bore due to the smaller base circle. The amount lower is the stock base circle diameter minus the new base circle diameter divided by two (or the stock base circle radius minus the new base circle radius). Now that you know how much lower the lifter sits, you get a pushrod that much longer and you will then obtain your original lifter preload. The stock lifters start getting noisy at less than 0.080" of preload from what I have read.
Note that injectors can be noisy, carbon in the cylinders can cause a tick and with headers any noise will be like putting it through a megaphone compared to the thick stock manifolds.
Note that injectors can be noisy, carbon in the cylinders can cause a tick and with headers any noise will be like putting it through a megaphone compared to the thick stock manifolds.
Advanced
Joined: Mar 2005
Posts: 74
Likes: 0
From: PA
ticking
I had a head and cam package installed with all of the new guts as well, dual springs, rockers, pushrods, valves, dual chain timing. My builder warned me that the drivetrain would produce more noise but that it was still bullet proof, just alot stiffer moving parts to produce more power.
I have about 5k miles on the install and either my hearing is going or the noise just dosent seem as loud
I have about 5k miles on the install and either my hearing is going or the noise just dosent seem as loud
Racer
Joined: Mar 1999
Posts: 413
Likes: 0
From: Pennsville, NJ
I think it definitely has to do with the ramp characteristics of the cam lobe (most likely the closing ramp). However, nobody has said WHAT is clicking. Is it the valve closing on the valve seat? Is it the lifter coming off of the cam lobe? Is there +0 lash in the lifter/pushrod/rocker because of deflection? Something has to be MAKING the noise...
Le Mans Master
Joined: Dec 2005
Posts: 8,475
Likes: 332
From: Port Arthur, Texas 77642
Apparently Lunati thinks they have a solution. You have to scroll down almost to the bottom to see the LSX series cams. Anybody running these cams or know anything about how they perform?
http://www.holley.com/types/Chevy_Voodoo_Cams.asp
Scotty
http://www.holley.com/types/Chevy_Voodoo_Cams.asp
Scotty
916/795 rwhp C5R 412 YSI
Joined: May 2005
Posts: 287
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I wonder if it is the fact that the CAM has been replaced or most everyone that replaces the CAM usually has headers installed also, which tend to be a much thinner exhaust and allow the valve train noise to be heard much clearer than stock exhaust manifolds? Just a thought.
Le Mans Master
Joined: Aug 2003
Posts: 9,298
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From: American Canyon Lethal Injection
I wonder if it is the fact that the CAM has been replaced or most everyone that replaces the CAM usually has headers installed also, which tend to be a much thinner exhaust and allow the valve train noise to be heard much clearer than stock exhaust manifolds? Just a thought.
Thread Starter
Melting Slicks
Joined: May 2005
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From: Leon Iowa
St. Jude Donor '06-'07-'08-'09
yes I agree with ya but like you said, they were solid lifters. A hydrolic lifter shouldn't sound like a solid lifter..
Le Mans Master
Joined: Aug 2003
Posts: 9,298
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From: American Canyon Lethal Injection
I'm ordering a set for my swap.
Some say quieter operation. With proper preload, they should last a long time. They are designed to handle 8000rpm operation and heaby spring pressures.
Also, the oil band and inlet are slightly higher on these lifters. This ensures that they get properly oiled with the smaller base circle aftermarket cams. With stock style lifters, the band has a tendency to drop too low in the bore and leak oil away from above the lifter causing two issues...lower engine oil pressure, and poor lifter oiling.
Hammer
Drifting
Joined: Oct 2004
Posts: 1,345
Likes: 3
From: Mesa Arizona
here is the info I got from Hammer69 on the Caddy Race lifters.
I'm ordering a set for my swap.
Some say quieter operation. With proper preload, they should last a long time. They are designed to handle 8000rpm operation and heaby spring pressures.
Also, the oil band and inlet are slightly higher on these lifters. This ensures that they get properly oiled with the smaller base circle aftermarket cams. With stock style lifters, the band has a tendency to drop too low in the bore and leak oil away from above the lifter causing two issues...lower engine oil pressure, and poor lifter oiling.
Hammer
I'm ordering a set for my swap.
Some say quieter operation. With proper preload, they should last a long time. They are designed to handle 8000rpm operation and heaby spring pressures.
Also, the oil band and inlet are slightly higher on these lifters. This ensures that they get properly oiled with the smaller base circle aftermarket cams. With stock style lifters, the band has a tendency to drop too low in the bore and leak oil away from above the lifter causing two issues...lower engine oil pressure, and poor lifter oiling.
Hammer
I also believe the only solution to this problem is a lifter swap and lastly, only if necessary, a stronger oil pump. It's got to be because of the aggressive cam profile and extra spring pressures that the stock lifters aren't getting "pumped up" enough.
How soon are you going to try the new lifters?
Bob