Cylinder wall imperfection- to sleeve or not to sleeve?

[S14kouki805]

So I'm rebuilding my blacktop SR20 block after melting piston #1.

Cylinder wall took some damage, machine shop bored it out to 87mm and it still has a small imperfection, sort of like a small divot, enough to feel with a finger nail. He described it as about as wide as a dull pencil tip. I'd post a pic but I forgot to take one when I went down there.

Obviously the concern is the rings or lands catching the divot and fucking up my freshly rebuilt engine.

Anyway, he's saying I could roll the dice and run as 87mm pistons, or get the one cylinder sleeved and go 86.5 across.

My last option would be to source a used block which I really don't want to do...

What says the Zilvia community???

[Koukiii]

So I'm rebuilding my blacktop SR20 block after melting piston #1.

Cylinder wall took some damage, machine shop bored it out to 87mm and it still has a small imperfection, sort of like a small divot, enough to feel with a finger nail. He described it as about as wide as a dull pencil tip. I'd post a pic but I forgot to take one when I went down there.

Obviously the concern is the rings or lands catching the divot and fucking up my freshly rebuilt engine.

Anyway, he's saying I could roll the dice and run as 87mm pistons, or get the one cylinder sleeved and go 86.5 across.

My last option would be to source a used block which I really don't want to do...

What says the Zilvia community???

Deff get it sleeved. Imagine building the motor and that cylinder takes a shit. You will sleep a lot better at night with a sleeve or another block.

[ultimateirving]

Do it once do it right. Like the guy above me said, you want reliability or short term savings?

[cotbu]

I agree with the sleeving, but I would go back to stock bore on all. Unless you already have over bored pistons. Or are planning some monster build

Sent from a Highly Tuned Note 4.5!!!

[Arrowking]

I'd go ahead and get it done right. No sense in putting it together just to have it have a ring failure within 100mi.

Of the two remaining options, I'd go ahead and source a used block instead of sleeving one cylinder. Sleeves can reduce the cooling ability of the cooling system so I definitely would get it done on all four or not at all.

[S14kouki805]

Thanks for the responses, at this point I am now considering just buying a used SR20 and parting out what I don't need.

The estimate is about 2g's for a rebuild, I know it will be essentially a new engine but for that price I could get a used block and save a shitload of money.

My concern is rolling the dice on a used engine...any input on this?

[cotbu]

They're all used engines, yes even the one you have now!
2g's for a rebuild is nothing as long as you're doing the labor. Shops here charge $1500-$1700 for a tear down/rebuild, not even installation of any new parts.

So this is where you put on your big boi pants or large female panties and make the decision for yourself.

[S14kouki805]

They're all used engines, yes even the one you have now!
2g's for a rebuild is nothing as long as you're doing the labor. Shops here charge $1500-$1700 for a tear down/rebuild, not even installation of any new parts.

So this is where you put on your big boi pants or large female panties and make the decision for yourself.

LMAO- yes you're correct...fuck why does shit have to cost so much!:facepalm:

[Arrowking]

Thanks for the responses, at this point I am now considering just buying a used SR20 and parting out what I don't need.

The estimate is about 2g's for a rebuild, I know it will be essentially a new engine but for that price I could get a used block and save a shitload of money.

My concern is rolling the dice on a used engine...any input on this?

I agree with the other poster, if you can go ahead and swing for the rebuild (better than getting a used motor)! If you mean just a used block and transferring all your stuff to that one then I'd go that route instead of a used shortblock. Heck, I'd even go one step further and get them all sleeved (if I had the cash). My thoughts are, just one sleeved cylinder is an unnecessary complication.

[S14kouki805]

UPDATE: Went ahead and got the rebuild done with just the one cylinder sleeved, they did an awesome job.

I'm thinking of starting a build thread, stay tuned.

[KAT-PWR]

You only sleeved one?
I'd be curious to see a heat map of an engine with one sleeve, i don't know much about them but im guessing the sleeve is made out of a stronger material with different heat capacity. How does this effect tuning or deviation across cylinders?

*waitsfortalontogivemeanextremelylongwindedexplana tionthatcouldprobablybesummedupinfewerwordsTLDRplz

[jr_ss]

I know a local guy that sleeved one cylinder. The motor cracked the remaining material between cylinders and started using coolant as a result. I think the best option is to sleeve all of them if you have to sleeve one. More money up front, yes, but sleep easier at night knowing it'll be fine.

[S14kouki805]

The work was done by pretty reputable shop, they suggested just doing the one sleeve.

I could see how it may affect cooling but I doubt it will cause any major issues.

We shall see!