Cylinder walls-what to do??

[PRattenbury]

I suppose I know the right thing to do already, but after the head was pulled from my engine, reality showed its face. I was hoping to put my new head on, and a new cam, and put things back together after a lot of cleaning and painting. The problem is the truck has 226,000 miles on it, which isn't too awful bad for these engines. The other problem is, all the cylinder walls have vertical scuffs in them. Number 5 has a scuff that can be felt with a fingernail. The engine didn't run bad before I took it apart, no significant blow by. But given the age of the engine and the presence of the scuffs, I'm pretty much unable to justify putting performance goodies in it and running at the power levels I want to run. My trust in my luck tells me I would regret that decision before long. Since I've already pretty much committed about 10 grand to the head, cam, pump, turbo(s), and so forth, the pockets are feeling the pain. Would the most efficient way to get myself straightened out properly be yanking my block and sending it off to be freshened up, or buying a reman short block (which would leave me with yet another spare cam). I'm definitely all for getting it balanced. Would I be able to run 800 horses on the street without studs, girdle and that sort of thing? Would coated pistons be worth it? Are Arias or Mahle better? Knowing my timing will be set at 24 degrees, is there anything along the lines of head gasket thickness, cam timing, certain types of piston tops that would make the components work the best together? Delays, delays, delays....

[joefarmer]

I would go ahead and do the block for peace of mind unless you plan on keeping EGTs under 1300 at all times. We put a 24v together with vertical discoloration in #5- it doesn't appear to be lacking any HP with cool twins (1380F max EGT).

bnraond.

[PRattenbury]

Yeah, the damage doesn't appear to be awful, but I can feel it in #5, which worries me. Actually any scoring does that to me. What would cause this? Overheating maybe? Running with no oil? EGT's?

[joefarmer]

Can you feel it with your fingernail or your finger? If it's your fingernail and not your finger, then it's around .0001" of a groove. If you can feel it with both, then it's gonna be deeper. Like I said, we've done both- rebuilt and ignored it. The trucks we see with higher EGT have deeper score marks. EGT kills these engines and everyone still runs them insane.

brandon.

[PRattenbury]

I can feel it with a fingernail. Can't really feel it with my finger. Number 5 is like that. The rest have visible scoring, but can't be felt.

[duke1n]

Brandon, can you elaborate on EGTs killing these engines? Mine has seen 1500+ for several seconds more times than I can remember and it lools new. Just curious at what level things begin to hurt?

[joefarmer]

Hmmm. I don't know if I'm the best at this kind of advice, but I'd throw everything together and see if you can keep the EGT down.

bnraond.

[Signature600]

Originally Posted by joefarmer

. EGT kills these engines and everyone still runs them insane.

brandon.

Boy you're one to talk

Pot is calling the kettle "black" too
Chris

[PRattenbury]

Well, consensus seems to be put it back together as-is and continue to flog. Sounds good to me. I thank you, and my wallet thanks you.

[Signature600]

What's the worst that could happen... If it works, you saved, if it doesn't you'd still have to fix it. Might as well see what happens!

Just don't hurt any of those other parts your installing, and you could re-use them if something "bad" happens

Chris

[joefarmer]

That's what I was thinking. I don't think you'll maim any of the parts you're putting on by running with scuffs. And yes, "everyone" includes me with the high EGTs.

bnraodn.

[Jim Fulmer]

Call me a Cowboy or a Knucklehead but If I saw that I would say........that's nice and put the head back on. This is the reason we need bigger piston to wall clearences on or motors.

Jim

[12vchevydually]

i would have to say Run it! I have seen worse!