What is the max, an ls7 [4.125] can be over bored? Is it .005 or ?? How much can the line bore be cleaned up? Can any head [ls] fit with proper head bolts and gasket? THANKS IN ADVANCE FOR HELP, JC

 

i wouldnt go more the .005-10" , yes any ls head will fit the block with the proper head gasket and head bolts

 

So can it have a bore of 4.135in. Is that the end of the block's life? Custom pistons?

 

Has any one built a destroked engine? 4.125 bore and 3.622 stroke?

 

not that i am aware of

Thanks

Nick--

 

if you were really going to spend that kind of money on an ls7 you should even be looking at that block. seriously.

 

LOL, I don't agree with that. It seems that the LS7 Block has taken some bad raps.
It depends on your horsepower level. I have heard of problems with the sleeves on some road race applications but you can have that with any sleeved application.
The masses seem to want more cubic inches. That is fine but there is a point where your gains diminish. For a street application you cannot beat the torque generated by a large cubic inch engine with a long stroke. For a racing application there comes a point when I will make more power (and reliability) with a shorter stroke. We don't have the heads at this time to support a full out large cubic inch deal. (440+ cubic inches)
I want to try some 380 to 400 cubic inch combinations with the currently available heads. I think they will make just as much power as some of the big inch deals.

I think that the LS7 block would be a great base for a 500 to 700 HP short stroke engine.
Now just wait until we can get our hands on the LS9 Blocks.



Robin

 

I'm going to build a destroked engine. I thing with a 4in. stroke, It has a lot of pison speed! I also agree with Robin. I truly think that there is a sweet spot[cu.in. to head flow] althow not written. Can these blocks be resleeved? thanks JC

 

What oil pumps are being used? I am thinking about a katech.

 

Steve at Race Engine Development can resleeve the LS7 and any aluminum block for that matter. I would check with him on the max oversize bore after resleeving. He can also resleeve the LS1/LS2 blocks to a 4.125+ bore also... Which might be more cost effective for strength anyway.

 

You should do some research on LS7 blocks. The bad rap is there for a reason. If your going to re-sleeve it why waste the money on that block? An ls2 block is much cheaper. 4.135 is what we are taking my sleeved ls2 out to.
Why would you destroke and ls7 ???

 

PISTON SPEED,PISTON SPEED,PISTON SPEED!!!!!!!!!!!! I know that everyone is in love with big cubes. Ls1,ls2,l92,and lsx all have the some bore length,ls7 is longer. This will help piston skirts live. thanks JC

 

So you think your going to make more power by destroking or make the car quicker? We dont have issue with piston skirt and the 4" stroke. Some inexperienced builders have selected improper pistons and had issue but this is not the case in our builds.

 

Pro stock 500 cu.in 7inch stroke? NO!!! I am going to rev this thing to the moon!! I love crazy rpm. It's kind of like cutting wood with a chain saw. The work isn't that fun, but running the saw is! I tape NHRA and strain my eye's to see what rpm they stage and leave the line at. Also when they shift.

 

I'm am not resleeving at this time. Just want to know if it is posible in future? What oil pumps are being used?