427 cu.in. LS-1/6 blocks with Darton MID sleeves

[SaudeKeep]

Now available - a complete list of FAQ's regarding the proper machining methods and correct installation proceedures for the Darton MID sleeve kit in the LS1/6 block. These come directly from Darton and Steve @ Race Engine Development (patent holder). Send me an e-mail, lcwolf03@comcast.net, and I'll reply with an attachment (it's 6 pages long). Many questions have been asked about how to resleeve LS blocks and this will provide accurate answers for anyone interested - especially engine builders.

[DocBowtie]

send a copy to cyphur_traq@yahoo.com.

[Mr.Attitude]

damn now thats the kinda first post i like!!!!!!! we need to keep this guy around. :grin2:

[mySStery_machine]

Great information Wolf, keep it coming....and welcome!

[DocBowtie]

Steve Demerjian backed you up over on LS1Tech as very knowledgeable about the sleeving process and such. Very Impressive!! I'm looking forward to seeing your write up :-D

[obseSSed]

Welcome, nice first post!

[DocBowtie]

thanks for the email Howard....I'll take a look at it tomorrow when I get a chance!!

[SaudeKeep]

response to a post from Scoggin Dickey (TX) concerning the strengths of the C5R block vs the LS blocks releeved with the Darton MID liners.

Nicky,

What I would like to see from GM is a race quality block that has priority main oiling and larger diameter head fasteners (or perhaps more) and larger main fasteners. Both in aluminum and iron. A tall deck version allowing longer strokes would be a welcome addition as well.

I believe you were refering to one of my posts regarding strength of MID sleeves. The material specifications and quality control for the C5R castings are impressive. The C5R aluminum cylinder walls and material used to make the iron liners however are no where near as strong as the material used to make the MID wet sleeve.
I have always stated that the MID cylinder was superior to anything on the market and I will stick by it. I do not work for Darton by the way but am closely associated with them.

You may not realize that Darton makes sleeves for the vast majority of Top Fuel and Funny car teams. They also make both wet and dry liners for many tractor puller diesels. A top fuel engine produces in excess of seven thousand horsepower. The supercharger on top of the engine provides over fifty pounds of boost. Peak cylinder pressures are upwards of 15,000 pounds per square inch. Cylinder pressure info comes from Austin Coil. A diesel tractor puller engine runs upwards of 100 pounds of boost. I do not have peak cylinder pressures for these engines, but the numbers must be impressive. Darton also supplies replacement liners to several cup teams but the power these engines produce pales in comparison to the ones above.

The MID sleeves and in fact every sleeve Darton makes is made out of the exact same material as their top fuel line of sleeves. This material is centrifigally cast ductile iron. The grade is based on a highly modified 100-70-03 ductile iron. The 100 stands for 100,000 psi tensile strength minimum, the 70 stands for 70,000 psi yield strength, the 03 is a measure of elongation (ductility). Now, the alloy used by Darton is considerably stronger and more ductile than 100-70-03. Tested tensile of the Darton material is between 110,000 psi and 130,000 psi tensile strength. Darton specifies an elongation of not less than 5% but most tested sleeves come in at near 9%. They have put some thin wall replacement style liners in a press and pushed the liners oval without breaking. They usually have one on display at PRI. Try that test with one of your "special" material liners and see what happens.

The C5R liners are .060" thick centrifigally cast gray iron (roughly 50,000 psi tensile) backed by 34,000 psi (at the very best) 356T6 aluminum alloy parent block material. Darton makes a replacement liner for the C5R by the way. The MID sleeve is over .200" thick (120,000 psi average tensile strength) at the thinnist point @ 4.160" bore. Even if the C5R liner were made out of Darton ductile iron, there is no possible way the liner and aluminum wall could be as strong. It does not take a rocket scientist to see that.

If people were driving over their crankshafts, I would say there is a structural problem with the standard production blocks or modified with MID sleeve blocks. I have not heard of this happening however. I believe that GM does an excellent job of casting the stock blocks from 319 T6 aluminum which is just about as strong (31,000 psi) as 356 T6. It is however not as ductile.

Another thing I should add is we went to great lengths in the design of the MID sleeve to provide for much improved cooling than on the siamesed bore castings. There are several coolant slots milled between the siamesed walls of the MID sleeves to prevent hot spots. This in combination with the patented coolant groove and transfer holes in the sleeve flange area greatly reduce the chances of detonation related engine failures.

In any event, we are all on the same side here. We love cars that go fast and do our best to find ways to make them better and faster.

Off topic a bit but when do you anticipate the release of the LS7 head castings? I have many people asking even from over seas.

Sincerely,

Steve Demirjian

[DocBowtie]

Keep 'em comin Howard!!

[marianne125]

Damn!!!!!