Generation III Internal Engine 1997-2006 LS1 | LS6
Sponsored by:
Sponsored by:

How much compression?

Thread Tools
 
Search this Thread
 
Old Dec 30, 2016 | 11:43 AM
  #1  
blacknyellow's Avatar
Thread Starter
On The Tree
iTrader: (3)
 
Joined: Jan 2011
Posts: 172
Likes: 0
From: Columbus, tx
Default How much compression?

I am thinking about buying a fresh 408 stroker from a guy. He said the following
aluminum 6.0 bored 30 over, eagle 4.000 crank, 6.125 howards rods, and diamond +10 pistons.

goals are street truck (s10)
Currently stock ls1 on 150 shot
Want to put this 408 together with the 799 heads I got and a 228/232 cam and two kits probably 250 shot.

what compression ratio am I looking at?
what would yall do?
h/c/i lts and nitrous.
Reply
Old Dec 30, 2016 | 12:31 PM
  #2  
khaotic's Avatar
On The Tree
iTrader: (2)
 
Joined: Jul 2007
Posts: 165
Likes: 1
From: Warrenton, VA.
Default

Originally Posted by blacknyellow
I am thinking about buying a fresh 408 stroker from a guy. He said the following
aluminum 6.0 bored 30 over, eagle 4.000 crank, 6.125 howards rods, and diamond +10 pistons.

goals are street truck (s10)
Currently stock ls1 on 150 shot
Want to put this 408 together with the 799 heads I got and a 228/232 cam and two kits probably 250 shot.

what compression ratio am I looking at?
what would yall do?
h/c/i lts and nitrous.
Gonna need more info to determine compression ration but nitrous loves compression, What cc are the heads what head gasket thickness, how far are piston out of the whole to be able to come up with compression.
Reply
Old Dec 30, 2016 | 12:33 PM
  #3  
JoeNova's Avatar
Restricted User
 
Joined: Mar 2014
Posts: 7,192
Likes: 109
From: Ohio
Default

Diamond sells forged Nitrous LS pistons.

The 408 pistons with a 10cc dome designed for LS6 heads are part number 11565.
These 10cc pistons with a 64cc chamber (799/243 heads) puts compression around 13.6:1.

With 317 or LS3 heads, compression is around 12.5:1.
Reply
Old Dec 30, 2016 | 12:44 PM
  #4  
farmington's Avatar
TECH Fanatic
iTrader: (14)
 
Joined: Jun 2010
Posts: 1,807
Likes: 13
From: Little River SC
Default

You can't bore an aluminum block .030 over.
Reply
Old Dec 30, 2016 | 12:53 PM
  #5  
JoeNova's Avatar
Restricted User
 
Joined: Mar 2014
Posts: 7,192
Likes: 109
From: Ohio
Default

Originally Posted by farmington
You can't bore an aluminum block .030 over.
Technically you can, there isn't anything stopping you.
Its been done a few times with some success. I don't know how well it would go with 13:1 and nitrous.
Reply
Old Dec 31, 2016 | 10:21 AM
  #6  
blacknyellow's Avatar
Thread Starter
On The Tree
iTrader: (3)
 
Joined: Jan 2011
Posts: 172
Likes: 0
From: Columbus, tx
Default

I thought it was only the la1 block that couldnt be bored much. Should I be concerned about sleeve thickness?
stock thickness fel pro gasket is what i've got.
the motor is in pieces new in box, just needs to be put together.
Reply
Old Dec 31, 2016 | 01:11 PM
  #7  
blacknyellow's Avatar
Thread Starter
On The Tree
iTrader: (3)
 
Joined: Jan 2011
Posts: 172
Likes: 0
From: Columbus, tx
Default

Dude said it has darton sleeves is there any way ro tell by looking at them? They are brass colored
Reply




All times are GMT -5. The time now is 03:39 PM.

story-0
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-1
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-2
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-3
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-4
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-5
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-6
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE
story-7
Awesome K5 Blazer Restomod Comes With C7 Corvette Power

Slideshow: A heavily reworked 1972 K5 Blazer swaps its off-road roots for a low-slung street-focused build with modern V8 power.

By Verdad Gallardo | 2026-03-09 18:08:45


VIEW MORE
story-8
10 Camaros You Should Never Buy

Slideshow: There are thousands of used Camaros on the market but we think you should avoid these 10

By | 2026-02-17 17:09:30


VIEW MORE
story-9
10 LS Engine Myths That Refuse to Die

Slideshows: Which one of these myths do you believe?

By Verdad Gallardo | 2026-01-28 18:10:11


VIEW MORE