Scratched Cylinder Walls
 

Bought a block off of someone and of course I didn’t check it out much, it was late. I took the guys word that it was good etc. Come to look at it today that it has some cylinder wall scratches. The block has more than 5000kms on it and it was driven hard. Daily’d a bit at 450hp and then at the track at 650hp to when he decided to forget Honda’s and move on.

https://cimg5.ibsrv.net/gimg/honda-t...b08ccc1dd.jpeg
https://cimg0.ibsrv.net/gimg/honda-t...8b4c877cc.jpeg
https://cimg3.ibsrv.net/gimg/honda-t...51ead6d71.jpeg
https://cimg5.ibsrv.net/gimg/honda-t...f0ad90d56.jpeg
https://cimg4.ibsrv.net/gimg/honda-t...aa44cb517.jpeg

Almost all of them I cannot feel. But cylinder #3 I can slightly feel it when I run my finger nail over it. Would a light gone and some new rings help? Guy says I can run it like this as he had no problems and it drove fine like this. Need some input on what I should do. Thanks!

Re: Scratched Cylinder Walls
 

He says they are not scratches but ring marks. There is only 1 scratch that I could feel

Re: Scratched Cylinder Walls
 

I've always been told/heard that if you can't feel them they are fine. The one you can feel may pose a bit of a problem but I suspect not enough to impede running, just less power and blow by in that cylinder would be my assumption being he was already running it that way without "issue".

Re: Scratched Cylinder Walls
 

That last picture is pretty bad. No cross hatch left.

Either a lubrication failure or rings were too tight for 650hp.

Would be a good idea to tear it down and make sure everything is in spec for what you are planning. Also check for broken ring lands and wear in the ring grooves.

Could you toss it in and go? Yeah probably, I have run much worse.

Re: Scratched Cylinder Walls
 

Do you guys recommend doing a hone with new rings? I believe I can run it like this but would like the added insurance of adding new rings. I will be running 5xx hp. If I were to run it like this would there be excessive oil consumption etc? Could this be a piston to wall being too tight? Or just too tight rings? Sorry guys I have a lot of questions lol

Re: Scratched Cylinder Walls
 

If I were you since it’s apart rehone it and get new set of rings to avoid any what ifs... in the future and it’ll save you a lot of headaches so you know you done it right and was done by you.
And since he was pushing 600whp its a good time to look at your rod and main bearings to make sure it’s in good shape to run your new setup and know you can hit your 5xxwhp mark with ease. Measure everything within specs so you don’t have to worry down the road. Building a motor is an art, take your time bro.

Re: Scratched Cylinder Walls
 

By the looks of the pics looks like the piston skirts are scoring up the walls and looks like piston to wall is probably loose and out of spec. But who knows till you measure.