I do about 10x more reading on these forumns than posting, but if someone could explain this "sleeving" idea it would be great. From what I can gather, the "sleeves" are on the pistons, they go around the piston head. Basically rings. You can replace them, but nothing you can do at home by yourself.

People refer to "sleeving" their engine, does that just mean they are gonna replace the sleeves? Would the main purpose for sleeves be to keep compression in the cylinder, sort of a seil around the piston?

What is the main purpose for a "sleeve" or for getting an engine "sleeved" or "re-sleeved"?

Appreciate any clearing up anyone can do. Pictures always help

 

"Sleeving" refers to re-sleeving the block. Yes, the sleeves contain the pistons. Using a b18 as an example, if one wishes to make it a 2 liter engine without changing the stroke, they must re-sleeve the motor since it cannot be bored out safely beyond 82mm on the stock b18 sleeves. Re-sleeving will allow (potentially) the motor to be bored out to 84.5mm, or roughly 2.0 liters. In summary, re-sleeving, unless performed to fix damage, is done so that displacement can be increased without changing the stroke of the motor.

 

Thanks, that answers a good chunk of what I was looking for. Now for a few "secondary" questions if you don't mind.

A sleeve is a ring (10mm or so in thickness) that encloses the piston. How deep is a sleeve? Its job is to prevent leakage of air/fuel down the sides of the piston?

 

The sleeves are the actual CYLINDERS that the Piston goes into. "sleeving a block" refers to cutting the stock cylinder walls and inserting a new "SLEEVE"

Here is what it looks like:


These are pressed in the block and put in place of the stock sleeves. Note how they are thicker than the stock ones. These sleeves can be bored out bigger than the stock sleeves.

Here's a block with stock sleeves:


Heres is a block with Exospeed Sleeves installed:



Modified by exospeedAMcrx at 1:28 AM 8/22/2003

 

Wow, that is awsome, thankyou. So, correct if I'm wrong, if you sleeve your engine your making the hole in the sleeves larger in diameter, in turn, would you not have to replace the pistons with a wider piston to cover the entire cylinder?

So true or false?
This whole process should give you larger displacement.
The compression ratio would be lower assuming nothing else changes, as there is larger displacent but stoke is the same. Or would compression be the same, seeing more air would be allowed in?
It would be best to adjust your A/F ratio to compesate for the larger displacement.

Sorry I have tons of questions regarding compression ratios, a/f ratios, under all different kinds of applications (boosted, all motor etc...) Trying not to ask too many at once.

---

A general question about compression. Speaking in general. If you have a standard 10:1 compression in a Car.

Suppose you turbo charge, changing compression to 12:1 would be best allowing more room for the addition air/fuel coming into the cylinder?

Suppose you are all motor, compression would be better suited at 8:1 to be albe to compress the air better?

 

Sleeving the block will let you increase the bore size, but you can also stick with the stock bore size.

In many blocks that we do, the customers choose to stay with a 81mm bore on their B series, which is the stock bore. Even with a sleeved block, they chose not to increase the bore size. Maybe just in case they want to go bigger later, they have enough "meat" on the sleeve to bore to what they want.

Bigger bores such as 84mm bore(vs 81mm stock bore) will increase the displacement of a 1.8L B18 block to a 2.0L without changing the stroke. The displacement is increase through BORE size.

On your compression comment, its opposite:
High compression such as 12:1 will be for ALL MOTOR applications.
Low Compression such as 8:1 will be for Turbo.

Wil
Exospeed.com

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by issues4 &raquo;</TD></TR><TR><TD CLASS="quote">... So true or false?
The compression ratio would be lower assuming nothing else changes, as there is larger displacent but stoke is the same. Or would compression be the same, seeing more air would be allowed in?</TD></TR></TABLE>Maybe your CR gets higher. When you increase your bore, you have to get bigger diameter pistons, and you have the opportunity to use a thicker or thinner head gasket. Any of these things changes CR, so it's hard to say 'nothing else changes'.

 

Can not just bore your stock sleeves?

I thouhgt I'd heard before that they were too thin to bore. If indeed stock sleeves are too thin, and you replace them with thicker sleeves, would'nt that in turn just decrease the diameter of the cylinder? and would have to bore them to stock size or thinner?

Is there any boring done to the actual block when inserting thicker than stock sleeves?

 

The stock sleeves can only be bored to 82mm safely.
No sleeving doesn't decrease cylinder bore, sleeves are thicker towards the water jacket(look in the pics; in the sleeved block the water jacket is smaller than stock).

 

the water jacket is the area between the block and the sleeves, just so you don't get confused.

Resleeving will get you strength in the sleeves because they are a stronger material and they are thicker. There are also "closed deck" designs which elminate the water jacket for the most part. The thing about stock honda sleeves is that they can crack because they are like a cantilever if extra pressure is induced when the piston reaches the top of its motion.

Thats is why you will also see something called a "blockguard" which acts as a brace that sits in the water jacket and reinforces the stock sleeve using the strength of the block. It is not as effective as sleeving of course. I hope some of this made sense.

 

Yeah, that makes perfect sence thanks. I kinda figured thats what the water jacket was, but to think that there would be open space between the block and the sleeve sounded odd.

On a stock engine the water jacket is actually empty space between the sleeves and block. Is that where the coolant runs threw to cool the engine? If it is, then does'nt resleeving or placing a blockguard stop the coolant from doing its job?

 

Yes, thats where the coolant runs through. Blockguards and sleeves were supposed to both be designed to not impede coolant flow. However, some people have trouble with overheating. I don't remember if it's a particular company's sleeve/blockguard or what. It is also said that blockguard can warp cylinders and create "hot spots". This taken care of by making sure the blockguard is the same shape as the cylinders when it is installed and the fit is not super tight. Metal expands with temperature, so you can imagine what happens when a bunch of things are expanding with no place to go. The weakest one will fail in some way, which is the sleeve.

 

Sounds good.

What is it that keeps the sleeves in position, if there are water jackets on either side of them, and the crank casing below them...? I'm fairly sure they could'nt be connected to the head. Are there spacers inside of the water jackets that hold them there? I hear of having to press the sleeves out.

 

I'm not sure HOW they are connected to the block, but they attach to the block at the base of the sleeve. Thats why I called them a cantilever, they are fixed at only one end.

 

Oh right, cantileiver (forgot what that meant). Thanks for all the input guys, that answers just about everything.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ricodemus &raquo;</TD></TR><TR><TD CLASS="quote">I'm not sure HOW they are connected to the block, but they attach to the block at the base of the sleeve. Thats why I called them a cantilever, they are fixed at only one end.</TD></TR></TABLE>When it's all assembled, the top end presses against the headgasket, so they aren't really cantilevered.

 

I'm planning to run a turbo setup next summer at low boost (6-7 psi) on a B18B and the thought of resleeving has crossed my mind. It's my understanding that the stock sleeves aren't incredibly strong, but at the same time, running this amount of boost should be ok. However, my main concern is keeping the engine as reliable as possible and having the engine last me for at least four years boosted at 6-7 psi (I'll be at college without my car for a lot of that time, so it's not as bad as it sounds). For this, would it be recommended to resleeve with something stronger?

Now, at the same time, someone said that resleeving could lead to overheating issues. I imagine this would only get worse with a turbo setup. Are there any ways to resleeve or reinforce the cylinders without running into overheating issues?

Thanks in advance,

Brian

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by JimBlake &raquo;</TD></TR><TR><TD CLASS="quote">When it's all assembled, the top end presses against the headgasket, so they aren't really cantilevered.</TD></TR></TABLE>

ok, I gotcha, I was just thinking about it without the head on it, like in the pictures. But yes, when loads are applied its not actually cantilevered. I just used the term to describe its condition without the full ongblock assembled.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by brianSilverTeg &raquo;</TD></TR><TR><TD CLASS="quote">I'm planning to run a turbo setup next summer at low boost (6-7 psi) on a B18B and the thought of resleeving has crossed my mind. It's my understanding that the stock sleeves aren't incredibly strong, but at the same time, running this amount of boost should be ok. However, my main concern is keeping the engine as reliable as possible and having the engine last me for at least four years boosted at 6-7 psi (I'll be at college without my car for a lot of that time, so it's not as bad as it sounds). For this, would it be recommended to resleeve with something stronger?

Now, at the same time, someone said that resleeving could lead to overheating issues. I imagine this would only get worse with a turbo setup. Are there any ways to resleeve or reinforce the cylinders without running into overheating issues?

Thanks in advance,

Brian</TD></TR></TABLE>

Stock sleeves can hold ok if it is tuned well. The key is to not detonate and control the combustion temperatures properly. 7 psi tuned is well within reach.


As far is the overheating issue, I may be jumping the gun on sleeves being the cause. Do some searches in the FI forum and find some more info. I think it's more of people not following directions with headgaskets and maintaining their block correctly.