Build #1

I have a factory LS1 block and I want to know if use aftermarket sleeves what is the max bore that the block can handle. What i am trying to ask, What is the most cubic inch LS1 factory alluminum block for race only you guys have heard of. I have already used the search button which is useless on this. The only thing I have found is that the block will handle 1000hp. This will be a NA very high compression build. I want alluminum block for light weight reasons. If its not possible thats fine I am new to LSX race only.

Darkman

iTrader: (2)

The Darton sleeve for the LS1 comes with a bore 4.165 which would yield 395 CID and can be bored up 4.20 which would yleld 401.6 CID.

Build #1

What Stroke can I run with a 4.20 bore, I would like the largeset stroke with that bore. I would be happy with 440 cubes if its possible.

Darkman

iTrader: (2)

Assuming you went to a 4.00" stroke, which is the basis of the popular 383 cid configuration, the base Darton sleeve at 4.165 yields 436.16 CID with the Max at 4.20 for a yield of 443.52. The 440 CID would require a bore of 4.1833".

Presumably you use something less than the absolute max of 4.20" bore to permit subsequent boring/honing operations if needed.

Steve - Race Eng

iTrader: (1)

You can build a 454 cubic inch engine which would be 4.185" bore and 4.125" stroke. You can also go to 468 cubic inches, same bore 4.25" stroke like the block I did for the Hot Rod Magazine cylinder head test posted elsewhere on LS1 Tech.

Engine life will be shorter with the 4.25" stroke so keep that in mind. I sleeve a lot of blocks that are built into 454" engines.

I MID sleeve little Honda blocks that make over a thousand horsepower!

Steve

sciff5

iTrader: (1)

so if a little honda motor can do it why is it so difficult with the ls1

garygnu

the honda is a 4 valve with a turbo.

Build #1

Thanks Steve, I will need to talk to you more on this. Engine life is not whats important, The absolute most power is what I am going for. The 454 cube is what I will be interested in the most. To bad I would have to send it to you from Tennessee.

transamfreak01

iTrader: (8)

why stay with the ls1 though and resleeve? all the money your going to spend could be used towards a completely new, stronger build. if alum is what you want then why not do a ls2 bored out? i just dont see the point in maxing out a ls1 if you could spend the same money pretty much and still have room to grow for later on

AAK z28

iTrader: (18)

sounds like a lot of work and potential problems just buy a gm lsx bowtie block

COPO9560

A MID sleeved LS1 block is significantly stronger than a bored out LS2 block. Stronger than a dry sleeved LS2 block as well.

To the OP - cubic inches are your friend but the key to the most power is in your cylinder heads & valve train. Sleeved blocks are expensive, as is anything with a 4.125 or larger bore in LS land. Don't spend all your money on the short block, top NA hp will require some expensive heads, solid roller valve train as well as sheet metal intake. Total costs will be very high.

If all you want is high NA power, it would be cheaper to build a 582 or 632 BBC.

Build #1

Its just a fun challenge, always wanted to join the LS croud, big block is the easy way out.

sciff5

iTrader: (1)

I think theres a little more to it than that. I was looking for a more detailed answer. Most people have an issues with the stock block ls1 at 1000whp

Build #1

Heres your detailed answer.....Less Power Less Stress.LOL A Honda 4cyl(stock block) making 1000 hp has a power adder. Im sure you think they will make a 100 more 1/4mile passes too.lol