BlackBirds

iTrader: (24)

I'm in the middle of a cam install, and when I pulled out my factory cam I noticed at the peak of a couple lobes the cam is beat the hell up. It looks just like a worn bearing, how it pits up. I tried taking pictures but none of them turned out and you can't see anything.... Anyway, I'm sure someone with knowledge of the issue will know what I'm talking about. What causes the cam to get chewed up like this? Are the lifters on these lobes failing? Maybe the valve spring allows the lifter to bounce on the cam? Its only at the peak of the lobe where this is happening.

This engine was bone stock before this, and has 60,000 miles on it. Thanks for any input!

Darkman

iTrader: (2)

Valve float.

BlackBirds

iTrader: (24)

i'm fine with valve float, since the stock springs are obviously comming out and Patriot dual golds are going in. But the cam being beaten up begs the question....if a hardened cam is that abused, then do the lifters on these lobes need changed out?? Obviously I don't want to remove the heads if I don't have to, but if the lifters need replaced then they need replaced. Any way to test them except for pulling them out?

Darkman

iTrader: (2)

The lifters (rollers) require visual inspection. Another way to accomplich that, (other than pulling the head(s)) would be to use one of those inspection tube/snake camera devices like some plumbers use.

joecar

A set of OEM lifters is currently about $107, cheap enough to change if there's any doubt.

GM PART # 12499225 lifters, LS7, kit of 16.

Darkman

iTrader: (2)

I agree and I would change the lifters, but there is another $150 or so in expense for head gaskets, lifter trays, and head bolts - not to mention the 8 or 10 hours of work.

SSmoked1

iTrader: (21)

Your right and it sucks you need to worry about it but are you willing to roll the dice with you motor for an extra day of work and $200? You have the whole front apart already, the heads really are not that big a deal at this point. Do it the right way and have no worries. Or....

BlackBirds

iTrader: (24)

yeah...shelling out another $200 for parts sucks, but I'm the kinda guy that wants to do it the right way the first time. Besides...if I have a lifter fail I'll be paying out the ***, so I'm just thinking of it as preventative maintenance

01ssreda4

iTrader: (96)

Lifters should be replaced IMO.

Always2Slow

iTrader: (8)

there is nothing more heartbreaking then installing everything and driving for a couple thousand miles and then you get this ticking or slight knocking sound of your brand new cam being trashed because a roller was messed up and took out a lobe on your 400 dollar camshaft.

bigpat501

iTrader: (5)

samething happend to my buddys vette and the lifters were trashed i wouldnt risk it replace them

BlackBirds

iTrader: (24)

Yeah, it sucks but I have to do it, for peace of mind if nothing else. Thanks for the input guys, heads are coming off near the end just before re-assembly to replace the lifters.

So LS7 lifters are the way to go? How are they different from LS1's? I did some reading and saw that many people are going with shorter pushrods with the LS7's than with the LS1 lifters. With the LS1's in place I measured 7.4" to be the right length pushrod, and I've already bought them. Should I still be alright with the LS7 lifters and this same size?

PREDATOR-Z

Since you measured before, measure again once everything is back together and only then will you know for sure if you have the right size.
I would also get new lifter trays while you are at it.

blazer427X3

I think the pitted look you describe occurs when you start to go through the heat-treatment on that lobe. When you pull the lifters out you probably find that they have the same pitted look on the roller as well, mine did.

BlackBirds

iTrader: (24)

yes, that pitting on your cam is exactly what happened on mine, except mine is worse

Is there any way I can just get the LS1 stock lifters, or are the LS7's the new stock replacement? I would very much like to be able to use the push rods I paid for already....


Edit: I accidentally said "I would very much like to be able to use the lifters I paid for already...." When I meant push rods not lifters. I already purchased a set of 7.4" push rods for the cam install, and I would not like to buy another set of 7.35" if it can be avoided.

408Maro

iTrader: (14)

From what I understand ls7 lifters replace the ls1's

blazer427X3

I think that is true and if I remember right, even though the lifter might look slightly different it still has the same length. You can still get stock LS1/LS6 lifters if you want. I've seen new sets of Delphi and Eaton stock lifters on the auction site.

Link below will give you more info about lifters than you might want to know, it was written by an engineer who works for GM.

http://forums.corvetteforum.com/c5-t...ic-lifter.html

PREDATOR-Z

Correct, LS7 lifters are the replacement lifters. They are however a bit taller at the cup area. Once installed, proper p-rod measurement should be taken, sometimes they require .050' shorter p-rods (cam specific)

jamesSS

+1 Im with this guy. Cheap insurance for a long healthy engine.

BlackBirds

iTrader: (24)

So what kind of problems could you run into if your push rods are .05" longer than "ideal"