Cylinder scratches

Well I have my opinion but I want to hear from people that know. Check out these scratches tell me what made them they are in all cylinders but this one caught my eye that alerted me to the rest. There is brown in the scratches, kinda of a mixture of nasty oil condensation and rust but it wipes off. The engine has been sitting awhile. Now, I can't hardly feel them with my fingernail, but I can with my finger.

Pull it apart, clean it, dingle berry hone it (lightly) and run it. Measure the clearances and make sure the are correct while you're in there.

Look like old grey forged trw-s or such, id have to guess your .005 isnt enough, more like .008-.009 or better.

Ya kinda confirms what I was thinking.

Pretty good eye you are correct on the pistons

Really think it's necessary to tear down and rehone and regap? It's got a 1000 miles on it,but they are quarter mIle hard miles nothing above 6000. In my mind I probably should but I just wanted to avoid that.I need to hear some nonbiased opinions

Non-biased opinion: It's ugly in there and should be torn down and dealt with.

However, that's obviously not the answer you want to hear.

Your oil isn't hot enough before beating on it

Those skirts are not like the newer TRW and speed Pro forged 440 pistons, they looklike the original forged 426 M.W TRW pistons
Did you gap the rings and deburr the ring ends? If not you should have If you did then those scratches maybe from junk suck into the cylinders and got stuck between the top of the pistons above the ring lands and cylinder walls

To me they look just like the trw replacements from the early 70-s.

OP. what motor is this? What do you know about the pistons.

It's 68 440 I built it in the 80s, used trw pistons,l and used a ring filer and checked the gap inside a fresh bored 030 block. But the did sit a couple years at a time. I used to run it at the track. Damn good motor ran 12s in a challenger. Was just going to swap it to another car thought I'd take peek inside.Ring gap was dead nuts on when I put it together.chrome moly

I agree..... Freshen it and run the piss out of it...

I've always thought it was pretty amazing how imperfect things can be and still function admitably well for what they are.

Myself I would hand hone or machine shop touch hone and re ring it, but.....If you don't, it will be just as good as it was. I'm more inclined to repair and improve things while they are apart.

I would have it honed on a good Sunnen honing machine with a torque plate to remove the scratches and make the cylinder round and seal good
Once you get the heads off you will be able to see more, sometimes things look a lot worse than they are
How many runs on the motor and rings?
If more than 30 put new rings in it
I don't like or use low tension oil rings any more unless the motor has a vacuum pump on it
Please let us know what you find and decide to do

What weight oil and what is the coolant temp when staging the car?

Take it apart and check clearance.

20 50 @ 180 degrees , but it's a street engine now . I'll take the heads off and get a better look. But most likely i will take it apart and fix it right because it will always bug the [censored] out of me if don't . I'll see what my machinist says first.

If the scratches aren't deep with nothing protruding it is what it is. If it gets honed to true it up remove everything chances are the piston to wall could be excessive. What is the purpose of honeing and leave the scratches? Make it pretty?.
Looks like a low buck piece. I'd run it.
Doug

Could always hone it and spend a couple hundred bucks and get the skirts coated.

True Doug you make a good point

I'll take the heads off go from there and throw some trick flows on it and beat on it some more, and have fun, that's what it's all about for me

To me it looks like just about every old TRW heavy slug - stock rodded engine after a few years of running! - the skirts on those pistons always seem to have had a funky edge on them from the forging process - we used to dress them with a honing stone. If it has good ring seal now run it if not - give it a quick dingle ball hone hone and run it - those pistons are pretty forgiving when it comes to clearence as long as its not too tight.

This for everyone who wanted to know.
Talked to my machinist, who's also a drag racer take a piston out look at it and ,"if it's not black death don't worry about it" which is the skirt gaulding the cylinder wall leaving black lines on the piston skirt.clean the cylinder wall with WD40
So I'm good to go.

If they are only black on the back side i.e. the non thrust side that's from running a plug that's too hot. I've seen it many times. Back siding is usually the wrong plug.

Really? No black,but When you say back side do you mean toward the cam and why would a hot plug cause that? Running lean?

Run it. The scratches are what they are, and were there when you ran it last. That little bit of surface rust will hurt nothing. That'll get wiped off in an instant. Then if there is any tiny pits, they'll just hold oil.

Also those are nothing in terms of scratches from what i see in the pictures.