Cstraub

iTrader: (1)

Sidestep,
Your located in the Tri-Cities aren't you? If so if you want me to send that lifter off to Morel for analysis we'll let them cut into it.

Chris

SideStep

Sure no problem... How do I get it to you???

Thanks,
Scott

FYI, the LS2 lifter tray part#
GM PART # 12595365

GuitsBoy

iTrader: (4)

That what I thought too. If you run springs heavy enough to control the valves, they should keep the lifter in constant contact, which should be more than enough to overpower the plastic. the only thing I could think of is that as the lifter ramps over to nose of the lobe, its inertia reduces the pressure of the roller against the backside of the lobe. A spring may have just enough pressure to keep the valve from floating, but it may not have enough pressure to overcome the plastic retainer which twists the lifter on the backside of the lobe until it meets the base circle again and pressure comes back. Its just a theory, nothing more.

SideStep

Guitsboy,

With the LS2 tray did you put the "indentation" up or down when you installed them in the block, see pic below... the bottom tray is the LS2...

GuitsBoy

iTrader: (4)

Actually, theyre still sitting on a shelf. Im still waiting to get a chance to mill my heads, so I dont want the lifters sitting in an open motor for all week before I can put the heads back on. But thats a good question, i dont know which way to install them. Something tells me it dosnt matter much one way or the other. I think it may have something to do with the ls2 blocks, and why the ls1 retainers wont work in them.

SideStep

You are correct about that... The LS2 blocks have material that fills that area...

GuitsBoy

iTrader: (4)

So which way are they oriented in the ls2? It stands to reason that what works in the ls2 would work in the ls1 in this case.

SideStep

good thinking.... I am looking for a picture of a LS2 short block now...


Found it or at least a LS7... looks like the indent is on the bottom. I included the thread link also...

https://ls1tech.com/forums/generation-iv-internal-engine/446435-ls-2-disguise.html

2blue

I can't believe a $5 over the GM counter replacement PLASTIC part is good enough to prevent the roller lifters from skewing on the cam lobes! Shows how far plastic technology has advanced.

GuitsBoy

iTrader: (4)

Thanks for soing all the leg work, sidestep! I cant get over how thin the material is between bores on the block. looks like you could poke through it with your finger.

Cstraub

iTrader: (1)

Stepside is going to get me one of these lifters and I will send it off to Morel for analysis.

cantdrv65

iTrader: (3)

Hmmm. My lifters after 47,000 miles and a comp XER lobe cam (for 25,000 with Isky springs) look like mirrors.....back in they went. This time with the PRC duals. Oh forgot to mention they were also slammed pretty hard when I recently busted a timing chain and bent 10 valves!

Teutonic Speedracer

iTrader: (20)

The #10 lifter tray has one lifter slot on the end cast on an angle. It pretty much has the lifter rotated ~10 degrees so that the edge of the wheel can dig into the cam. I only had one bad lifter out of the batch and it was on the #10 casting (the one bore that was rotated). Of course mine is on a roadrace motor that saw ~4k miles at sustained HIGH rpm.

jub jub

After examining the lifter trays, I can understand how it can happen. I really never paid much attention to them and last night I took a good, long look at one and I can honestly say, I've been enlightened.

My trays were numbered 12, 13, 14 and 14. But after looking at my lifters real close, I think one or more trays might have a problem. I will have to examine them further when I have time.

Here's a pic of one of the rollers. Looks good doesn't it.

D'scamaro

how can you tell what lifter trays you have

also, how can you tell if a lifter if collapsed, i know what to look for on the roller part but how can you tell if it would be bad or not , thanks dwayne

becuase i had some low oil press and it starting knowcking a bit, dont know if the lifter froze up or just got dry of oil and when i get good oil pressure, itll be fine or what??? thanks guys

HavATampa

iTrader: (49)

Hey Sidestep,

Here's some pics of your old cam. I'm no expert, but it doesn't look good. Not only are a lot the lobes scored, but the back of the cam is showing high heat marks. Not sure what causes that. Maybe someone else can chime in with their opinions on this cam. I took a couple of shots of another used Comp Cam for a side by side comparison. I don't think I will be bringing it to Thunder Racing unless you want to me to get their opinion also.




















RIP Mamanator 2.0

8a8mfh

iTrader: (3)

They will turn if theres nothing stopping them. Look at the old flat tappet lifters, if they DON'T turn they fail. In normal operation they rotate.
Roller lifters HAVE to stay perfectly inline with the cam lobe.

SideStep

Thanks Randall... The end of the cam is normal, I have other CompCams cams with the same coloring...... The lobes are not...


I may send the came back to Comp for analysis...

jub jub

I understand that. GM should have used a girdle between pairs like comp and the other manufactuers instead of plastic pieces.


I want to know why the cam and lifters in the pics failed.

8a8mfh

iTrader: (3)

From what I understand the #10 lifter tray does not hold the lifters in a perfect line with the cam, so then as the engine runs the roller is riding the cam at an angle, this causes friction and that causes the failure seen in the picture.