Block Sleeve length LS1, LS2, LS6 LS7 and L92.
What is the length or depth of these different blocks?
When adding a 4” stroke or more I understand some part of the lower piston will come out of the sleeve.

Which will have the longest factory sleeves?

Which after market sleeves are the longest?

I am thinking of building a solid roller N/A 427 street/strip engine with LS7 style heads.
I am looking for the most affordable option, but yet durable.
Bob

 

i think i read somewhere that the deck height of the ls7 block is actually shorter than the other ls blocks

 

The LS2 and LS6 blocks have a sleeve length of 5.400". The LS7 has a sleeve length (to the tang) of 5.900".

I had Darton lengthen all the wet and dry sleeves to 5.800". The original designs were 5.675" which were good for 4" stroke or 4.125" stroke using a short skirt piston design. The 5.800" sleeve will accomodate 4.250" strokes.

The main problem is honing. The distance from the deck to the main bearing webs is 6.250" on all these blocks. In order to properly hone a cylinder, you need clearance (overstroke) past the bottom of the sleeve. The 5.800" Darton sleeves leave .450" overstroke for honing. Most shops will not have difficulty with this overstroke length. Another thing is you don't want the sleeve sticking out of the bottom of the block any great length unsupported. The Darton sleeves stick out .125" the LS7 .225".

The Darton sleeve is very strong so it will not spring away from the honing stones where it overhangs into the crankcase that .125". The LS7 sleeve requires a lot more effort to keep round and to size at that overhang of .225" effectively shortening the overstroke to only .350". The gray iron is about 1/3 the strength of the Darton sleeve as well which makes it even more difficult to hold size and out of round in the overhang section of the sleeve.

The C5R block is even worse in this regard. Sleeve length is 6" leaving only .250" stone over travel for honing. That combined with the gray iron liner sticking way out into the crankcase makes for a very difficult honing job.

Seve

 

Steve,
Thanks for the great info
Bob

 

Do not use the iron 6.0L truck block it is too short. 3 quarts in 300 miles RIP 402.