The LS2 Darton dry sleeve is finished! The centrifugally cast ductile iron liner is designed to safely bring the LS2 block to bore sizes between 4.125" and 4.155" diameter.

Two of the main problems of dry sleeve installations have been carefully thought out and addressed in this new sleeve. First, the flange seating width is more than sufficient to keep the sleeve from "dropping, or recessing" into the block deck. This was accomplished by making the flange diameter larger than the bore spacing. Flats are machined on the flanges where adjacent liners meet. Second, sealant grooves have been machined into the lower section of the sleeve. This was done to allow special sealant to fill the grooves to eliminate any possiblility of coolant seeping into the crankcase in the unlikely event the block cracked behind the sleeve. This cracking is much less likely in the LS2 block since it has no coolant space between the liners as in the LS1 and LS6 blocks. Also the outside diameter of the LS2 aluminum cylinder wall has been increased by GM to 4.800" from 4.600" on the earlier blocks giving much better support of the oversized liner.

I have posted photos showing the start of the machining process, the seating shelf in the deck, the finish machined display block, the new sleeve showing flange flats, sealant grooves and crankshaft cut out, and finally the sleeves dropped into the block.

Note that these sleeves must be installed on CNC mills that are coolant equipped to maintain the required machining tolerances.

These sleeves are not a replacement for the much stronger MID sleeves. They were specifically designed to provide an economical means to safely increase bore size to 4.125" + for street and moderate racing use.

The sleeves will sell for around $800 a set. I will machine your clean used block for $750 including installation and decking. A brand new, unused block must be stress relieved at additional cost.

Steve

 

So the step holds the sleeve in place and u dont cut into the water jackets..
ME LIKES

 

What kind of power output would this thing hold? Roughly

 

If you have a problem with dropping sleeves you can weld a beed around the bottom of the cylinder and then have a shelf at the top and bottom. I have done some custom sleeves that just fit without putting flats on the sides in a LS1 this way.

 

Interested in hearing more...

 

looks bad *** steve, i gotta stop by soon and see them in person.

 

Steve, yet again you blow us away with your skills. Great work!

 

The LS2 block, Darton liner combination should be good for at least 800 hp. The Darton sleeves won't break as will the stock cast in liners. Pretty good support for the sleeve with almost a quarter inch of aluminum around it.

Someone else mentioned putting a step at the bottom as well as the flange seat at the top of the liner. That might work but you really want the sleeve to be able to expand and contract without being restricted on each end. Otherwise you will have trouble keeping the bore round in service. We also make this sleeve as long as possible to provide better piston skirt support for longer strokes. It is the same length as the MID sleeve with the identical crankshaft cut out. You would lose that extra wall length if you put a step at the bottom of the bore.

Steve

 

Sounds Good Steve!! I am thinking of selling my LS1 Block now

Brad

 

Sounds great. I was reading the 2 articles in GM High Tech performance. MTI was doing a 427 LS2 build with Dry Sleeves. I'm going to guess that is your Technology??? Looks alot like the same thing.

Ok. Quick question. Which is better; GEN III Sleeved block? or GEN IV Sleeved block?

 

The Darton sleeve is not what MTI is using. That is their own design.

If you compare my photos with theirs, (and other shops for that matter) you will see that the Darton sleeve has a larger flange diameter with side flats on the seating flanges between the cylinders. This is essential if you want a sufficiently wide seating surface to ensure the sleeves don't "drop" in service. The small block Ford and Chevy dry liners as used by Dart in their aluminum blocks have flats on the sides for this reason.

Most everyone else is using an off the shelf small block Chevy replacement style sleeve with no flats in the LS2. The Darton LS2 dry sleeve is purpose designed for the application.

Steve

 

What OD is the sleeve and the hat bore?

 

The flange diameter is 4.550". The upper body outside diameter is 4.325". At 4.125" bore you would have .100" wall thickness. At 4.160" bore (max. recommended bore size) you would have .0825" wall.

 

Nice work Steve!

 

I guess u wont have to run the Evans WP or Coolant with this type of setup?
This is the way I'd go if I built something bigger than a 402,very impressive Steve....

 

awesome very impressed

 

Steve YOU ARE THE MAN!!!!!!!!!!!!!!

 

You can run standard antifreeze with the dry sleeve. I always recommend the Evans pump because it is more efficient and better built than the stock piece especially the LS2 pump. The Evans pump improves flow and gives more equal flow from bank to bank than the stock pump.

The LS2 pump uses smaller bearings and shaft than the LS1 LS6 pumps along with changes to the stat housing. If you want to stick with a factory pump, I suggest you use one of the earlier non LS2 pumps.

Steve

 

Are the dry sleeves more reliable these days?? I know you are the man when it comes to sleeving blocks. I have been debating about doing a larger bore aluminum motor and putting upwards of 20 psi on it. I just want to make sure that the block will be able to handle it. and I have heard or read about horror stories of sleeves leaking or dropping. thanks in advanced.
thanks
Wesley

 

We took all the failures of earlier dry sleeve installations into consideration with the design of the Darton LS2 dry sleeve. As I mentioned earlier in this thread, the dry sleeve will work great in street driven and moderate racing usage.

There is no possible way for you to crack these sleeves. The aluminum block deck surface however my become overheated and softened with high boost and or nitrous. Remember, there is no coolant passage between the cylinders on the LS2 blocks. I highly recommend you using an MID wet sleeve LS1 or LS6 block instead which is bullet proof if done correctly. Darton will have an MID kit later this year for the LS2 by the way. The 4.200" MID wet sleeve for LS1 LS6 engines will be available shortly.

There is a shop in your area that can do the MID work according to my specs, with my equipment and training. I believe Howard has at least one finished MID block on hand you can take a look at. Give him a call at:
770-427-4294