FastKat

iTrader: (10)

I am the new owner of an LS2 engine block. It looks like the engine suffered from oil starvation. There is some scuffing on the cylinder walls and some marks in the lifter bores. The cylinder wall problem should be easy - boring and honing will take care of that. It's the lifter bores I'm concerned about. Most of them look good, but about 5 have some marks on them. 3 have scuff patches that look a little duller than the rest of the bore. The other two have some light scratches. I'm not sure how deep the scratches are, but they don't look bad. A few others have straight scratches running parallel with the bore. I'm not worried about those ones.

So the question is - how nice does the lifter bore need to be? I've had opinions from block apocalypse to expensive sleeves to clean up with a brake cylinder hone to "just run it." Anybody have meaningful experience/input here? Eventually I'll wind up taking it to a machine shop for an opinion, but I want to know what I'm talking about before I get there.

BTW, I know the pics aren't that great.

A.R. Shale Targa

iTrader: (2)

Those don't look too bad to me. As suggested, run a small brake cylinder
hone through there with some thread cutting or even motor oil. Just a few
licks to clean up the high spots from scratches. Definitely run new lifters
when assembling. The only time I've seen lifter bore issues is from a solid
roller lifter after 20,000 street miles...the bore became too large to then run
a flat tappet hydraulic lifter(oil pressure bleed off).....so I had to run a flat
tappet solid cam/lifter.
You could even run a link-bar style lifter for more stability if you're consider-
ing running a .650 lift cam.

KCS

iTrader: (20)

I would see what the machinist says. It's probably ok, but he may recommend honing the bore to straighten them out or even increase clearance if he thinks they're too tight.

Worse case scenario would probably be to have to hone it out for a .875" lifter. It's pricey compared to just throwing in a set of LS7 lifters, but its an upgrade for the valvetrain.

koolrayz

iTrader: (26)

Have the shop install bronze Bushings in the lifter bores, that will also give you better oil control on the top end

FastKat

iTrader: (10)

Thanks for the info guys.

I talked to the machinist today and he didn't seem to think it would be an issue. Rather than bore it to the next larger size, he said that he could resurface the bore with a hone. I'm afraid to do it myself and I don't want to mess it up!

The whole bronze bushing idea is pricey. At that point it almost makes sense for me to buy a new block!

koolrayz

iTrader: (26)

The point is you end up with a much better product than you would with a new block. Many people will bush the lifter bores in a brand new build , it is all about oil control.

FastKat

iTrader: (10)

I understand where you're coming from. They do seem like a good product. If I was building a max effort race engine then I would be all over them!

koolrayz

iTrader: (26)

The main reason I brought them up is that you would be better off using them to repair a good block then to start with a new block. They are not needed on a mild setup.

KCS

iTrader: (20)

How does it help oil control?

studderin

iTrader: (28)

ya, its not gona be about the bore issue, for the lifter to work in. Ive seen some race engine stuff get damaged, and had to use a hammer to get the old lifter out, then hand sand,scrap,file the bore cleanup so a new lifter would "move". And top and bottom of the bore get some heavy damage and the block last and runs for alot time with it.

But for the LS you need to look into the oil clearance of it. as ray said its the 1st clearness that loose, will **** off psi. stock LS oiling







Its alot of labor to bush all the lifter so look into that before you spend more money on the block. I think you could test is tho. To a good undamaged lifter bores. Put lifters in them (and cam) and put a oil PSI gauge before and after the lifter oil gallies, and see what the drop is. You can maybe even see the damages bores leeking more oil, but I dont know what I would compair good and bad about of leaking to. So the gauge bleed off data would be helpfull on that.

A.R. Shale Targa

iTrader: (2)

The best thing about bronze lifter bushings is the lubricity. It's a more porous
alloy that holds oil better. So they are both better 4 longevity AND repairable
in case and engine failure occurs. In this case the OP probably doesn't need
it but it IS the best...period !!!

FastKat

iTrader: (10)

Thanks for all that info.

I did not realize that the oil traveled through the bearings from the back of the engine to the front. My oil pressure sending unit is in the back of the engine - does that mean that it's not giving me an accurate reading of my oil pressure at the front of the engine?

Given my situation, it might be a good idea to get a ported oil pump or maybe even an aftermarket high volume oil pump.

studderin

iTrader: (28)