Where are the O-Rings located on the MID setup? Are these an item that need to be replaced due to wear? O-Rings are typicalyy made of rubber and can wear over time.

 

Also, what type of failures, regardless of how minute they may be, are inherent with this setup? Nothing is 100% foolproof in a sleeved setup, IMO so what are the things that are possiblities, no matter how rare, of trouble?

 

If you are skeered go with iron

 

I'd rather go C5R

Isn't there a con to going with the iron, other than weight? I thought most of the blocks must be sonic tested before being bored to 4.125"? I thought they could only be taken to 4.030"?

 

Man w/the power the 346's are making unless you are going Big time and looking for 600+ type horses stay w/the stock bore or slightly over....I mean it seems only a matter of time before 500hp is capable w/the stock cubes.

 

Stock bore size can not generate the same amount of tq, area under the curve, as can big bore/stroker combos. Peak, yes, but not area under the curve.

 

Hi Guys,
Landed a set of these revised MID sleeves for MY LS1 block a few months back for use in my 428CID project. Man they took a while. The supply had been delayed due to some technical gitches but I finally got my hands on a set. I was waiting anxiously for ages as they were still in testing and pre-production until mid-year. They are the first set landed in Australia and the first set fitted here. The machine shop selected was in another state but offered the best skills and CNC machining facilities available. This is a must for this kind of work.


The revised sleeves are a quality unit, They are finned to provide greater thermal stability...this is in addition to the qualities inherant to a wet sleeve. They are strong and as they are fitted in such a way as they lock and crush in, they add to the strength and integrity of the deck. Any core shift in the block is also less of a concern with this design (though obviously the less the better as always). The chance of one of these 'dropping' is greatly reduced due to the lip up top and the step at the bottom. Very nice.

Yes there is a trick apparently to fitting the #1 sleeve and the machine shope in Melbourne that did the fitting, noted, documented and fed this data back to Darton. They were appreciative for the info and are revising their already substantial milling and fitment instructions as a result. Looks like Darton are a switched on company that takes this kind of feedback very seriously. I'm glad to see in this thread too that they consult with shops on a regular basis...it's in their best interests to gather data from the field to provide a truely great product

I think most will agree that a quality Machine Shop is required to fit these and good to see a couple of them here discussing there experiences...well done .

The cam selection and manifold used in my motor sees less peak power but is set to be a real kitten to drive with stump pulling torque everywhere and power peaking at 5,600.... she'll never break. Maybe later when cam design improves for daily driven 'big bangers', I'll look for more power but for now, I'll stick to a low 240's single pattern. (I like to be able to run creature comforts like air conditioning without stalling at every set of lights and I need to maintain fuel efficiency).


Anyway...
Thought I'd give you a peek at my block and what it's going into:

 

I have attached a side view of an MID LS1 - LS6 sleeve. The o'rings (3) are located at the very bottom of the sleeve where the sleeve locates in the block - just below where the sleeve sits on the bottom of the coolant jacket (no way to drop a sleeve with these). Since this is a static assembly there is no wear on the o'rings. Nothing lasts forever but the o'rings will most likely outlast the engine by a wide margin.

All diesel trucks, trains, exotic imports - Alfa, Ferrari, etc. use o'rings on their sleeves. A diesel truck will run well over a half million miles before the sleeves are pulled during engine overhaul. O'rings are not a problem!

Note the coolant slots milled in the sides of the sleeve. Along with the cooling fins these measures help dissipate the heat from high output engines. The stock cooling system was designed for four hundred horsepower, not 500 or 600 or the 800 + horsepower some guys are pushing these engines to. This is why we spent so much time putting a system together, sleeves, coolant, pump, etc.

One problem we had early on was gasket sealing ie. water leaks between head and block. However, even the stock block is prone to leak. Keep in mind that these engines have only ten bolts clamping head to block. The small block Chevy uses seventeen bolts.

To address this issue Darton has posted photos on their web site showing where Loctite flange sealant needs to be applied to the Fel Pro 1041 gasket. This will eliminate any chance of leaks as long as boost is kept under ten pounds with this gasket. Over ten pounds and the head will lift off the block - only ten bolts!

Cometic is modifying their MLS large bore gasket to work with the Darton sleeve. I know Cartek is using the current gasket with no problems. The beauty of the Cometic gasket is the spring steel face. It will seal even if the head lifts off the block a bit. Most of the Honda racers use Cometic with the Darton MID sleeves. Those little 1600 - 1800 cc engines will produce close to a 1,000 hp at the flywheel with 35 lbs. plus boost. No leaks and the sleeves hold up just fine. The Honda sleeves all have o'rings by the way.

The very first MID sleeves were shipped at 4.060" bore and needed to be bored to 4.125" bore. Some shops neglected to chamfer the bottom of the sleeve after boring. This resulted in piston skirts lasting a few minutes after engine start up. No fault of the sleeve, just poor prep. Darton now puts a very generous chamfer on the bottom inside of the sleeve to eliminate this problem. We have also increased the overall sleeve length to accomodate the 4" + strokes some guys are running.

The iron block will not go to 4.125" bore. These aren't bow tie racing small blocks, they are thin wall production castings!

Steve Demirjian
Race Engine Development

 

Great Info you have made my week we are just about to start machining the block next week.

One query is it an absolute requirement to go with the evans cooling system. Not an easy thing to get when you dont reside in North America.

 

Awesome info Steve. Thanks a ton for posting. I feel pretty confident in my block now.

 

sounds like I'll be getting a 427 when i get back from this sand box.
where can i get the cheapest lunati crank?anyone
thanks

 

Steve, greatly appreciate all the info. The pictures help out tremendously. Are you able to fit the blocks with 4.125" ID sleeves or must they all be machined out from the 4.060" bore sleeve that is inserted?


So have there been any problems with sleeves, etc with the MID setup? No coolant/oil consumption issues with the MID setup assuming the headgaskets are sealed properly?

In a street driven car such as mine that sees lots of stop-n-go and heat cycles, will the sleeves have any negative effect over time?

 

I'd be pretty confident if I were you, also.

 

You can't bore an iron block to 4.125. (4.100 bore spacing)

The most I have seen is 4.080 after sonic testing BUT I wouldn't go that far either.

A 4.035 x 4 inch stroke 409 will make a ton of power and be DEAD reliable. With the right heads, cam, intake, header combo 510+RWHP and similar torque would be a piece of cake.

Bare block weight difference is only 60 pounds plus a new block is what 600 US? I think the new Darton setups are fantastic and I think resleeved alum is a great choice, but iron is definitely an option as well.

Cheers,
Chris

 

I agree, Chris but I want to keep the 427 displacement, just sounds cool . Plus my seats are embroidered to match the displacement, 7.0L. Can't have them clash now can I?

I can get a new GM 6.0L block for $695 shipped, roughly dealer cost.

 

The current MID sleeves come through at 4.112" - 4.115" semi finished. Next month they will be coming through at 4.100" and will need to be bored to get to 4.125". Some guys didn't like honing from 4.112" to 4.125" and it is difficult to bore a cylinder .008" to leave .005" for honing. It is a lot easier to bore .020" than .008" which is the reason for the change.

Lingenfelter has had a street car running for ten thousand miles with no problems. I'm pretty sure Cartek has a long time car as well. If the work is done correctly you will not have a problem with excessive oil burning etc. Any high output engine will burn more oil than a stock one however. This because of increased piston to wall clearance and lighter tension rings.

The only area in question in my mind would be really cold weather. We have no experience yet with anyone running these engines in winter conditions. Most guys would put their cars up on blocks as I used to do when I lived in Ct. but something to keep in mind.

 

When you say cold weather, what average ambient temperature are you referring to?

 

We would much prefer everyone used the Evans coolant with the MID kit. Why not visit the Evans site: www.evanscooling.com. If they don't have a sales office in your area you can e-mail them. I'm sure they will find a way to get you what you need.

 

Anything below twenty - twenty five degrees. The Evans coolant is good to forty below. The new racing coolant arriving soon is good for ten below. No problem as far as the coolant goes but we have no data on the engine at these temps and below.

 

What if the vehicle is garaged when it's parked but driven during those temps?