proautoman

Will a 4 " stroke Ls1 crank 6.125 rods and 4.125 mahle pistons go into the
Ls7 block wondering about the dry sump and length of the Ls7 crank
versus - Basically could you use this block which is less money than
a sleeved Ls1 or C5R block

Haans249

iTrader: (24)

If you're looking at a block with a 4.125 bore, go for the darton sleeved LS2 block with replacement LS7 sleeves, its cheaper and a stronger setup.

ram09

iTrader: (1)

how can you justify a "stronger setup" when you have to drill out the old cylinder liners, then heat up the block and press the new liners in? How does completely remachining a block make it stronger? I would think that heating up an aluminum block hot enough to slide a new cylinder liner in would distort the block, and thus weaken the block.

98Z28MASS

iTrader: (6)

Hmmm ive always been informed that resleeving a block with better sleeves, such as Darton sleeves, would only strengthen the block?

Haans249

iTrader: (24)

lol, you would think that putting in darton sleeves specifically designed to be stronger would be stronger....lol

ram09

iTrader: (1)

i dont doubt that the sleeves themselves are stronger, my concern lies with the block itself and the heating involved to install the sleeves.

Bill Reid

iTrader: (14)

Yes, a "regular" GENIII 4" stroke crank, along with a 24x reluctor wheel, will work in an LS7 block... along with the rest of the rotating assembly you are looking at. If you are replacing an existing motor then pull all the covers and reuse them. The exception is the valley cover which is LS2 style... and also an LS2 front cover along with a cam sensor adaptor/extension harness as I assume you will put this motor in an older GENIII based vehicle. Use an early 05 style LS2 cam sprocket and an LS1 crank sensor. Melling has great GENIII/IV oil pumps out now... maybe pick one of the high volume models up. Be sure to shim the windage tray down a bit and crank over the rotating assembly to make sure the rods will not hit the windage tray. I'm probably missing a few other details but I'm sure others can chime in too...
As far as price is concerned regarding a resleeved GM block (LS2 is preferred) versus a brand new LS7 block you need to shop around. If you are comfortable with a resleeved block and can get it cheaper keep that open as an option. The LS2 block dry sleeved has already proven itself to be very reliable... much more so than when LS1 blocks were being dry sleeved and stretched to 4.1+ bore.
As another option keep your eyes open for an L92 block and aftermarket progress on them... not quite the bore of an LS7 block but more than a factory LS2 and apparantly much cheaper than an LS7 block.

Shop, shop till you drop... you'll thank yourself in the end...

Bill

Steve - Race Eng

iTrader: (1)

Blocks are not heated to install sleeves. The sleeves are chilled in the refrigerator then installed into a room temperature block.

The centrifugally cast ductile iron Darton LS7 sleeves are much stronger than the gray iron factory liners. This allows one to bore them out to 4.1875" for normally aspirated use.

Steve

proautoman

How much is the sleeved LS2 block??

Dune-LS1

Just an FYI... The Melling oil pumps do not work with a double roller timing chain on a LS1 blocks and front cover... The Melling pump is thicker and it hits the timing cover when you space out the oil pump for the double row crank sprocket... I haven'r tried it yet with a LS2 block but I don't see why it should not have the same problem...

MEMPHO69

What type of oil pump will not hit a double roller cam sprocket or front cover on the LS2 engine.

Haans249

iTrader: (24)

a regular LS oil pump shimmed with the spacers provided with the chain.

Dune-LS1

^^^ What he said^^^

jsworkstd

I'd like to see some facts of how many LS7 block's liners have failed?
Were they N/A or high boost?

jsworkstd

Where are the failures???

11 Bravo

iTrader: (3)

Pics of one were posted awhile back. I believe it was sprayed. When the sleeves were removed to be replaced, the cylinders were shown to be poorly machined by GM. Found it

https://ls1tech.com/forums/showthrea...cracked+sleeve