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

High Compression LS6

Thread Tools
 
Search this Thread
 
Old Aug 12, 2009 | 10:58 PM
  #1  
C5natie's Avatar
Thread Starter
10 Second Club
iTrader: (1)
 
Joined: Jun 2007
Posts: 659
Likes: 5
From: SoCal
Default High Compression LS6

I currently in the process of building my LS6 with a forged botton end and domed pistons for 12:1-12:3cr. Ive looked in the internet and cant really find any info on anyone with an LS motor in the 12:1cr range. Only other guy I know is a 440ci LS7 on a '06 Z06. That LS7 is 12:1cr and a beast. Just wondering if anyone hear has a 347ci LS1-6 with high compression? If you do what is your performance/setup? There must be someone out there.

Specs:
347 LS6 block cleaned and honed
all new bearings (cam & crank) Federal Mogul
stock crankshaft
in house machined lightweight forged I beam (rated to 900rwhp)
domed forged pistons (yet to be ordered)
custom grind 228/234 112lsa cam
TFS 215cc heads, 60cc combustion chambers
3600 stall
3.42 gears
race built trans
Reply
Old Aug 13, 2009 | 11:27 AM
  #2  
J-Rod's Avatar
6600 rpm clutch dump of death Administrator
20 Year Member
Photogenic
Photoriffic
Shutterbug
 
Joined: Dec 2001
Posts: 4,983
Likes: 13
From: Texas
Default

Been there, done that. Instead of domes, we just used the stock bottom end and milled the heads to 55cc. When we went to a forged 347, we had a -4cc valve relief. We had a failry large cam for a 346 (244/248 112+0 LSK Lobe). So, we had the CR up to offset all the overlap.

Is this a "Race only" setup? Just wondering what the intended purpose is.
Reply
Old Aug 13, 2009 | 12:16 PM
  #3  
C5natie's Avatar
Thread Starter
10 Second Club
iTrader: (1)
 
Joined: Jun 2007
Posts: 659
Likes: 5
From: SoCal
Default

Originally Posted by J-Rod
Been there, done that. Instead of domes, we just used the stock bottom end and milled the heads to 55cc. When we went to a forged 347, we had a -4cc valve relief. We had a failry large cam for a 346 (244/248 112+0 LSK Lobe). So, we had the CR up to offset all the overlap.

Is this a "Race only" setup? Just wondering what the intended purpose is.
Well, thats a way to go too. Didnt think of it. I left the measurements to the machinist and to figure out the best way to achieve the compression. As for the motor, it will see more road course use with some street and will more than likely have a race fuel mixture in it. I want a high and fast revving motor that will get in its power band quicker. Thats why I went with I beams too.
Reply
Old Aug 13, 2009 | 12:34 PM
  #4  
awd2rwd's Avatar
Launching!
iTrader: (17)
 
Joined: Jun 2006
Posts: 251
Likes: 0
From: Tulsa, Ok
Default

Originally Posted by C5natie
I currently in the process of building my LS6 with a forged botton end and domed pistons for 12:1-12:3cr. Ive looked in the internet and cant really find any info on anyone with an LS motor in the 12:1cr range. Only other guy I know is a 440ci LS7 on a '06 Z06. That LS7 is 12:1cr and a beast. Just wondering if anyone hear has a 347ci LS1-6 with high compression? If you do what is your performance/setup? There must be someone out there.

Specs:
347 LS6 block cleaned and honed
all new bearings (cam & crank) Federal Mogul
stock crankshaft
in house machined lightweight forged I beam (rated to 900rwhp)
domed forged pistons (yet to be ordered)
custom grind 228/234 112lsa cam
TFS 215cc heads, 60cc combustion chambers
3600 stall
3.42 gears
race built trans
I have a 415ci LQ4 nitrous motor sitting in my garage that is right @ 12.8-13:1 compression with 62cc All Pros.....Q16 WEEKEND TOY
Reply
Old Aug 13, 2009 | 01:52 PM
  #5  
C5natie's Avatar
Thread Starter
10 Second Club
iTrader: (1)
 
Joined: Jun 2007
Posts: 659
Likes: 5
From: SoCal
Default

Originally Posted by awd2rwd
I have a 415ci LQ4 nitrous motor sitting in my garage that is right @ 12.8-13:1 compression with 62cc All Pros.....Q16 WEEKEND TOY
Nice. Must be a monster.
Reply




All times are GMT -5. The time now is 10:45 AM.

story-0
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-1
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-2
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-3
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-4
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-5
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-6
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-7
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
story-8
Five Reasons the Camaro Was the Most Pivotal Player in the Pony Car Wars 2.0

The world was a better place when it was still around.

By Brett Foote | 2026-01-23 09:20:37


VIEW MORE
story-9
10 Reasons the LS7 Is GM's Most Extreme Naturally Aspirated V8 Engine Ever

Slideshow: The 7.0-liter LS7 was designed for absolute cutting-edge performance.

By Verdad Gallardo | 2026-01-07 18:36:00


VIEW MORE