Cylinder wall imperfection- to sleeve or not to sleeve? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

S14kouki805 · 07-10-2015, 01:43 PM

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 · 07-10-2015, 02:07 PM

Quote:

Originally Posted by 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???

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 · 07-10-2015, 02:21 PM

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

cotbu · 07-10-2015, 09:53 PM

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 · 07-12-2015, 08:51 AM

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 · 07-13-2015, 03:03 PM

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 · 07-13-2015, 05:57 PM

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 · 07-13-2015, 06:22 PM

Quote:

Originally Posted by 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.

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

Arrowking · 07-13-2015, 06:38 PM

Quote:

Originally Posted by 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?

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 · 10-06-2015, 12:57 PM

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 · 10-07-2015, 08:52 AM

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 · 10-07-2015, 11:22 AM

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 · 10-07-2015, 12:24 PM

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!

07-10-2015, 02:21 PM	#3
ultimateirving Zilvia FREAK! Join Date: Nov 2010 Location: arizona Age: 36 Posts: 1,521 Trader Rating: (1) Feedback Score: 1 reviews	Do it once do it right. Like the guy above me said, you want reliability or short term savings? __________________ Z32 with lq4 swap Desert Street Scene \|\| Dssevents.com

07-10-2015, 09:53 PM	#4
cotbu Post Whore! Join Date: Sep 2005 Location: SWFL Age: 49 Posts: 3,318 Trader Rating: (3) Feedback Score: 3 reviews	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!!! __________________ LoverTechnologies "Half Broken Things!"

07-13-2015, 05:57 PM	#7
cotbu Post Whore! Join Date: Sep 2005 Location: SWFL Age: 49 Posts: 3,318 Trader Rating: (3) Feedback Score: 3 reviews	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. __________________ LoverTechnologies "Half Broken Things!"

10-07-2015, 08:52 AM	#11
KAT-PWR Nissanaholic! Join Date: Dec 2011 Location: US Posts: 2,040 Trader Rating: (11) Rides Gallery: KAT-PWR Feedback Score: 11 reviews	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 __________________ MRP Manufacturing*

10-07-2015, 11:22 AM	#12
jr_ss Post Whore! Join Date: Dec 2005 Location: Pa Posts: 6,410 Trader Rating: (35) Feedback Score: 35 reviews	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. __________________ My SR20VET Does your VTC gear rattle in your S14/15 SR? PM me.

07-10-2015, 01:43 PM	#1
S14kouki805 Zilvia Addict Join Date: Aug 2014 Location: California Age: 42 Posts: 808 Trader Rating: (5) Feedback Score: 5 reviews	Cylinder wall imperfection- to sleeve or not to sleeve? 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???

07-12-2015, 08:51 AM	#5
Arrowking Zilvia Member Join Date: Feb 2014 Location: U.S. Posts: 213 Trader Rating: (3) Feedback Score: 3 reviews	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.

07-13-2015, 03:03 PM	#6
S14kouki805 Zilvia Addict Join Date: Aug 2014 Location: California Age: 42 Posts: 808 Trader Rating: (5) Feedback Score: 5 reviews	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?

10-06-2015, 12:57 PM	#10
S14kouki805 Zilvia Addict Join Date: Aug 2014 Location: California Age: 42 Posts: 808 Trader Rating: (5) Feedback Score: 5 reviews	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.

10-07-2015, 12:24 PM	#13
S14kouki805 Zilvia Addict Join Date: Aug 2014 Location: California Age: 42 Posts: 808 Trader Rating: (5) Feedback Score: 5 reviews	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!