Building a 408 LS2 Stroker
Thread Starter
4th Gear
Joined: Mar 2010
Posts: 4
Likes: 0
Building a 408 LS2 Stroker
Hi peoples
Looking at making my LS2 a little stronger as I have warn my LS2 internals out. I have been running around with a Harrop/eaton 2.3 SC for the last 30000 miles and the poor thing is getting a little tired.
I would like to build a 408 stroker out of the LS2 bottem end to better cope with the SC.
What I am looking for is any re-build instructions. I am looking at doing the re-build myself with the help of a engine builder.
If someone has documented their own build and have some good notes and pictures, I would love to hear from them. In the mean time I will continue the search.
Thanks guys!
Looking at making my LS2 a little stronger as I have warn my LS2 internals out. I have been running around with a Harrop/eaton 2.3 SC for the last 30000 miles and the poor thing is getting a little tired.
I would like to build a 408 stroker out of the LS2 bottem end to better cope with the SC.
What I am looking for is any re-build instructions. I am looking at doing the re-build myself with the help of a engine builder.
If someone has documented their own build and have some good notes and pictures, I would love to hear from them. In the mean time I will continue the search.
Thanks guys!
Burning Brakes
Joined: Nov 2006
Posts: 793
Likes: 1
All you need to know 
http://www.cartechbooks.com/vstore/s...=3788&CATID=30
Also I could be wrong but I think most LS2 Stroker kits are 402.
http://www.cartechbooks.com/vstore/s...=3788&CATID=30
Also I could be wrong but I think most LS2 Stroker kits are 402.
Safety Car
Joined: Sep 2007
Posts: 4,359
Likes: 6
From: Los Alamitos California
St. Jude Donor '09
All you need to know
http://www.cartechbooks.com/vstore/s...=3788&CATID=30
Also I could be wrong but I think most LS2 Stroker kits are 402.
http://www.cartechbooks.com/vstore/s...=3788&CATID=30
Also I could be wrong but I think most LS2 Stroker kits are 402.
San
5th Gear
Joined: Aug 2009
Posts: 5
Likes: 0
I've never seen an aluminum LS2 bored out to more than a 408, and that's even pushing it to a certain degree. The 418 and 427 strokers are out of LS3 blocks.
Again, I'd be weary boring out the aluminum LS2 more than 0.010" as it decreases block strength. The blocks that get bored out to a max of 0.030 are the LQ9/4 iron blocks.
Again, I'd be weary boring out the aluminum LS2 more than 0.010" as it decreases block strength. The blocks that get bored out to a max of 0.030 are the LQ9/4 iron blocks.
Instructor
Joined: Jan 2008
Posts: 185
Likes: 1
From: Denton Texas
St. Jude Donor '09-'10
au contraire....
http://forums.corvetteforum.com/c6-t...d-upgrade.html
from the website:
"Core RED sleeved LS2 Block"
http://forums.corvetteforum.com/c6-t...d-upgrade.html
from the website:
"Core RED sleeved LS2 Block"
Safety Car
Joined: Sep 2007
Posts: 4,359
Likes: 6
From: Los Alamitos California
St. Jude Donor '09
I've never seen an aluminum LS2 bored out to more than a 408, and that's even pushing it to a certain degree. The 418 and 427 strokers are out of LS3 blocks.
Again, I'd be weary boring out the aluminum LS2 more than 0.010" as it decreases block strength. The blocks that get bored out to a max of 0.030 are the LQ9/4 iron blocks.
Again, I'd be weary boring out the aluminum LS2 more than 0.010" as it decreases block strength. The blocks that get bored out to a max of 0.030 are the LQ9/4 iron blocks.
http://katechengines.com/katech_inc/...hort-block.htm
San
Thread Starter
4th Gear
Joined: Mar 2010
Posts: 4
Likes: 0
All you need to know
http://www.cartechbooks.com/vstore/s...=3788&CATID=30
Also I could be wrong but I think most LS2 Stroker kits are 402.
http://www.cartechbooks.com/vstore/s...=3788&CATID=30
Also I could be wrong but I think most LS2 Stroker kits are 402.
This is old school stuff but from what I hear 402 is the common size for a Holden/Gm engine and 408 is Ford.
I have talked with a few built engine owners over here (Aus) and 408 seems to be the go.
I would like to have gone with a built Lsx cast iron 427 but would like to develop and test what I have as I go.
Why miss out on all the fun in between a stoke LS2 and a fully sick blown 512 big block
Last edited by dt_edition; Mar 26, 2010 at 10:19 PM.
Team Owner
Joined: Nov 2006
Posts: 21,136
Likes: 212
From: Long Island New York
In the future I'm looking at a stroker. A quality 403 should meet my needs. I have a Vortech T trim and if I turn up the boost it will give me a good shot more than I have right now. I dont need a 7 litre monster with FI. Thats more than I need for the street. Good thread, keep it coming.
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Former Vendor
Joined: Apr 2006
Posts: 2,470
Likes: 2
From: Portland OR
St. Jude Donor '10-'11-'12
You've got an LS2 which has a 4" bore from the factory.
We see two different things when people stroke them. They either leave the bore alone, don't true it up and stick a 4" stroke crank in and get a 402.
We clean/true up the bore .005 and get a 403.
OR we re-sleeve to produce larger displacements. The OP said he wanted to do this himself so re-sleeving is probably out.
Your going to want to take it to a local machine shop to have the block work done. Do you have all the tools required? Ever set clearances before? This is not s simple project if your going to do it right, you don't just bolt stuff together and torque it to specs. You can buy one of those from ebay cheaper than you can build one. You said you had an engine builder to help you right? He will probably have the tools so you should be ok there.
There is a great thread done by user name helicoil on ls1tech which covers everything. step by step he meticulously goes through the building process. I suggest you take a look at it to see what your looking at and to see how it's done.
We see two different things when people stroke them. They either leave the bore alone, don't true it up and stick a 4" stroke crank in and get a 402.
We clean/true up the bore .005 and get a 403.
OR we re-sleeve to produce larger displacements. The OP said he wanted to do this himself so re-sleeving is probably out.
Your going to want to take it to a local machine shop to have the block work done. Do you have all the tools required? Ever set clearances before? This is not s simple project if your going to do it right, you don't just bolt stuff together and torque it to specs. You can buy one of those from ebay cheaper than you can build one. You said you had an engine builder to help you right? He will probably have the tools so you should be ok there.
There is a great thread done by user name helicoil on ls1tech which covers everything. step by step he meticulously goes through the building process. I suggest you take a look at it to see what your looking at and to see how it's done.
Thread Starter
4th Gear
Joined: Mar 2010
Posts: 4
Likes: 0
Thank you 99 this is why I have posted a question such as this I want to do all the research now. Yes I would like to do as much as I can myself as an experience thing but with a lot of help from an engine builder.
Yes all the machining will be going out to machinists...the comments about the clearances and capacity requiring a re-sleeve is good information I want to be familiar with before starting the build.
The build will not start until mid July so I am trying to get all the good information now.
Try and do the job right the first time I say.
Yes all the machining will be going out to machinists...the comments about the clearances and capacity requiring a re-sleeve is good information I want to be familiar with before starting the build.
The build will not start until mid July so I am trying to get all the good information now.
Try and do the job right the first time I say.
Burning Brakes
Joined: Nov 2007
Posts: 1,083
Likes: 3
From: Buena Park CA
You have the right idea. Getting more cubic inches will get you more horses, but more importantly, more torque (seat-of-the-pants stuff)!
I've rebuilt many different types of engines and I know there is a limit to expanding the cylinder diameters, it's really pretty obvious as it simply weakens the block internally. One time I rebuilt a Chevy 350 block for a friend out to .030 over stock with a 400 crank. This yields 383 ci, so no problem as he had tons of fun with it. Then, his buddy (not mine) wanted me to do the same thing for him, but with expanding the cylinders out to .090 over stock; I was against it, but he insisted. For a daily work driver it wouldn't be a big deal as it would probably last a long time, but I knew he was going racing with it (600+ horses). About 500 miles later, he told me the block cracked between cylinders and all hell broke loose....I later built him a 383 like his buddy....I guess he's still happy with it. My point is, don't get too crazy with expanding the cylinders unless these sleeves will definately keep the blocks' internal strength intact.
I only build engines for myself now (and very close friends), so don't get any ideas, sorry......but have fun and it will be educational.
I've rebuilt many different types of engines and I know there is a limit to expanding the cylinder diameters, it's really pretty obvious as it simply weakens the block internally. One time I rebuilt a Chevy 350 block for a friend out to .030 over stock with a 400 crank. This yields 383 ci, so no problem as he had tons of fun with it. Then, his buddy (not mine) wanted me to do the same thing for him, but with expanding the cylinders out to .090 over stock; I was against it, but he insisted. For a daily work driver it wouldn't be a big deal as it would probably last a long time, but I knew he was going racing with it (600+ horses). About 500 miles later, he told me the block cracked between cylinders and all hell broke loose....I later built him a 383 like his buddy....I guess he's still happy with it. My point is, don't get too crazy with expanding the cylinders unless these sleeves will definately keep the blocks' internal strength intact.
I only build engines for myself now (and very close friends), so don't get any ideas, sorry......but have fun and it will be educational.
