New rings vs overbore

[turbogrill]

Hi,

 

I had a bad cylinder head overheating incident that resulted in a cracked aluminium head. For some reason there are some marks in the cylinder walls after this. At least I think it's from the overheat, was a fresh rebuild. Maybe head parts got into the cylinder. 2 of the cylinders are bad, the rest is spot less.

 

I can feel the ridges with my finger,  they go vertical from top to bottom.

 

It would save me a lot of time if I could just put in new rings instead of do a proper overbore. What would be the downside with only putting in new rings? Lower compression? More oil?

 

 

 

 

[Black Magic]

I would at least hone it, even if using the crappy parts store ball hones. If you can't hone the ridge down to less than fingernail grab I wouldn't use it. I would personally take a slightly oversized bore from honing vs the ridges. If a real freak you could file fit oversized rings or blank rings to your new cylinder honed bore, but check lots of spots and set it to the tightest point. If you can make sure the ridge is below the rest of the surface, you have a shot at it living. 

 

Worst case, the ridge has a high spot and wears into the ring and leads to a failure point. More likely it will really hurt your cylinder sealing, causing lots of blow by and power escaping out the PVC (rather than pushing the wheels) if it is high. If purely a depression (no raised point), it will burn more oil, have less power (blowby) and lead to a larger blowby volume you have to vent (pvc system up to that much?). 

[TiredBirds]

I'd try and hone it... then measure it. you could always sleeve that one cylinder.