LS7 lifter problems...
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 866
Likes: 22
From: Savannah GA
LS7 lifter problems...
I just finished...well attempted to finish a cam swap in an LT1 this past weekend.
I couldn't help but notice that alot of my lifters were very soft...and they aren't that old. Maybe 2k miles? I think it's rather odd that I can depress the plunger with my finger by hand. Half were soft...the soft ones weren't exactly full of oil, which might explain that.
The rest of the engine is getting oil just fine. I have a hard time believing that half of them went bad that soon. I'm not seeing any evidence of oil starvation up top either which makes me question if it's an oil supply issue.
What are your experiences with these? The ones I've gotten lately have made me question if these are a good option...
I couldn't help but notice that alot of my lifters were very soft...and they aren't that old. Maybe 2k miles? I think it's rather odd that I can depress the plunger with my finger by hand. Half were soft...the soft ones weren't exactly full of oil, which might explain that.
The rest of the engine is getting oil just fine. I have a hard time believing that half of them went bad that soon. I'm not seeing any evidence of oil starvation up top either which makes me question if it's an oil supply issue.
What are your experiences with these? The ones I've gotten lately have made me question if these are a good option...
Melting Slicks
Joined: Dec 2004
Posts: 2,653
Likes: 635
From: Dallas TX
the spring pre-load SHOULD withstand your finger pressure... They dont need oil in them for this. They will do this out of the box, dry.
If you shake the lifter does the plunger cup move around or are the springs just weak?
LS7 lifters arent the best quality out there, and they really arent an "ls7" lifter, nothing magic about them, its just the standard GM lifter now. Probably on its 3rd or 4th revision to bring them to "ls7" status...
Johnson lifters are far and away a better product. I will not use LS7 lifters again in a motor.
I, personally, wouldnt put a new cam in without new lifters and vice versa since the roller and the journals marry together. I helped a local guy do lifters on his LS2 about 4k miles after a cam swap and I think at least half of his lifters were dead...they were factory original 60k miles lifters though. New lifters and the motor was quiet again.
If you shake the lifter does the plunger cup move around or are the springs just weak?
LS7 lifters arent the best quality out there, and they really arent an "ls7" lifter, nothing magic about them, its just the standard GM lifter now. Probably on its 3rd or 4th revision to bring them to "ls7" status...
Johnson lifters are far and away a better product. I will not use LS7 lifters again in a motor.
I, personally, wouldnt put a new cam in without new lifters and vice versa since the roller and the journals marry together. I helped a local guy do lifters on his LS2 about 4k miles after a cam swap and I think at least half of his lifters were dead...they were factory original 60k miles lifters though. New lifters and the motor was quiet again.
Thread Starter
Burning Brakes
Joined: Sep 2003
Posts: 866
Likes: 22
From: Savannah GA
Springs are just weak. Not finding any physical damage or anything like that.
From what I can find, they like between .080 and .100" of preload...and they also like a good amount of oil pressure. With my 7/16 studs, I figure that's 1 3/4 turns of preload. I know alot of people like to run less. Might be giving up a few HP doing that, but should keep the lifters happy.
I'm thinking of disassembling and cleaning/inspecting them all, then putting them in, setting the valves and priming the engine with the intake off to make sure they are flowing adequately to the top end. I'm also going to be eliminating the oil filter bypass, upgrading the relief spring and upgrading the factory cooler, which wasn't a stellar piece to begin with. I've already spoken to Dewitt's about making a radiator for me with a driver's side EOC built in.
If they are still noisy, or I find any that bleed off rather quickly, they'll get ditched in favor of something else, and I'll eliminate them for future consideration as an option when building an engine.
Any time I do a cam swap or rebuild I tend to replace the lifters. I didn't this time because they had such low mileage on them. If they end up being junk I'll be disappointed but it is what it is.
From what I can find, they like between .080 and .100" of preload...and they also like a good amount of oil pressure. With my 7/16 studs, I figure that's 1 3/4 turns of preload. I know alot of people like to run less. Might be giving up a few HP doing that, but should keep the lifters happy.
I'm thinking of disassembling and cleaning/inspecting them all, then putting them in, setting the valves and priming the engine with the intake off to make sure they are flowing adequately to the top end. I'm also going to be eliminating the oil filter bypass, upgrading the relief spring and upgrading the factory cooler, which wasn't a stellar piece to begin with. I've already spoken to Dewitt's about making a radiator for me with a driver's side EOC built in.
If they are still noisy, or I find any that bleed off rather quickly, they'll get ditched in favor of something else, and I'll eliminate them for future consideration as an option when building an engine.
Any time I do a cam swap or rebuild I tend to replace the lifters. I didn't this time because they had such low mileage on them. If they end up being junk I'll be disappointed but it is what it is.
Last edited by dhirocz; Oct 23, 2018 at 05:23 PM.
Le Mans Master
Joined: Aug 2017
Posts: 6,939
Likes: 1,488
From: New Jersey
I used these in a truck, honestly, I remember the springs being soft after I set the preload and backed it off. But once it had oil pressure it was hard until I leveraged the oil out. They're fine enough for a mild setup. I don't think I used more than 3/4 turn from zero lash though.
Race Director
Joined: Apr 2003
Posts: 17,699
Likes: 1,667
From: moraga ca
Melting Slicks
Joined: Dec 2004
Posts: 2,653
Likes: 635
From: Dallas TX
They might not wear to the journal like on a flat tappet cam, but they still wear in together just like any metal to metal part in any engine.
Last edited by rjacobs; Oct 24, 2018 at 10:38 AM.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
Not a. Lifter expert. There's a slight difference between a LS and the GEN 2 LT1 lifter. Although LS lifters are commonly installed in GEN 2 LT1s, if in doubt I would get the LT1 / SBC lifters.
