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

5.3L or 6.0L Block

Thread Tools
 
Search this Thread
 
Old Mar 12, 2009 | 09:03 PM
  #1  
decker's Avatar
Thread Starter
Teching In
 
Joined: Jun 2008
Posts: 4
Likes: 0
Default 5.3L or 6.0L Block

Alright. Here's the deal. I've been doing tons of research for my upcoming build. I'm planning on using a Kenne Bell 2.8L blower as my power plant and I'm shooting for ~750-800whp on pump gas. I'm going to fully build the motor, but my question is "What block should I go with?" I've been given two options: 6.0L LQ9/LQ4 block OR a 5.3L LM7 block bored to 5.7L.

I've heard great things about both setups and have personally seen pretty high numbers on at least the 6.0L block. What do you guys think? Whichever block I choose is the full motor I will buy (ecu and all).

Thanks in advance,
Decker
Reply
Old Mar 12, 2009 | 10:49 PM
  #2  
conan's Avatar
TECH Senior Member
20 Year Member
iTrader: (5)
 
Joined: May 2004
Posts: 6,492
Likes: 6
From: Back in the Burg
Default

When you say a fully built moter do you mean a forged bottom end or a stock long block. A forged 6.0l bottom end gets my vote, more CI will be easier to make your power goals, Also if you have the $$$ you could get a stoker rotating assembly you would have a 402ci.
Reply
Old Mar 13, 2009 | 02:09 AM
  #3  
Dan Stewart's Avatar
TECH Enthusiast
 
Joined: Aug 2006
Posts: 502
Likes: 1
Default

There is no replacement for displacement.

Go for the cubes.
Reply
Old Mar 13, 2009 | 06:28 AM
  #4  
SweetS10V8's Avatar
12 Second Club
iTrader: (4)
 
Joined: Jun 2004
Posts: 2,580
Likes: 3
From: Michigan
Default

Take the 6.0L, not only for the gain in size but you wont have to bore it .100+ over to get it where you want to run it.
Reply
Old Mar 13, 2009 | 10:34 AM
  #5  
California-police's Avatar
Teching In
 
Joined: Sep 2004
Posts: 14
Likes: 0
From: Q8
Default

Take the 6.0L "
Reply
Old Mar 13, 2009 | 11:05 AM
  #6  
98z8uup's Avatar
TECH Fanatic
iTrader: (7)
 
Joined: Apr 2008
Posts: 1,111
Likes: 0
From: Covington ,GA
Default

Go with the 6.0
Reply
Old Mar 13, 2009 | 11:04 PM
  #7  
decker's Avatar
Thread Starter
Teching In
 
Joined: Jun 2008
Posts: 4
Likes: 0
Default

Thanks for advice guys. I will be building the bottom end with forged internals shooting for a 8.5-9.0 CR.

I know I'll have more displacement with the 6.0L block, but other than that are the any disadvantages to using the 5.3L block? Will it be able to handle the boost and power?

I'm honestly not too worried about displacement with power plant I've selected ($5k on a blower better do the job).

Thanks again!
Reply
Old Mar 14, 2009 | 01:34 PM
  #8  
decker's Avatar
Thread Starter
Teching In
 
Joined: Jun 2008
Posts: 4
Likes: 0
Default

Bump
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

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

 Verdad Gallardo
story-1

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-2

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-3

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-4

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-5

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-6

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
story-7

Awesome K5 Blazer Restomod Comes With C7 Corvette Power

 Verdad Gallardo
story-8

10 Camaros You Should Never Buy

 
story-9

10 LS Engine Myths That Refuse to Die

 Verdad Gallardo
Old Mar 14, 2009 | 02:28 PM
  #9  
SweetS10V8's Avatar
12 Second Club
iTrader: (4)
 
Joined: Jun 2004
Posts: 2,580
Likes: 3
From: Michigan
Default

Why are you bumping this, everyone has been unanimous, which is very rare.

What information are you missing that you still need?

If you want to run the 5.3L block, just do it, just don't bore it .100 over and expect it to hold 600hp.

Are you looking for someone to tell you its OK to run the 5.3L block? You are not going to overpower any blocks.... unless you bore it .100 over

Buy the stupid 6.0L and just be done.
Reply
Old Mar 14, 2009 | 08:08 PM
  #10  
decker's Avatar
Thread Starter
Teching In
 
Joined: Jun 2008
Posts: 4
Likes: 0
Default

Originally Posted by SweetS10V8
Why are you bumping this, everyone has been unanimous, which is very rare.

What information are you missing that you still need?

If you want to run the 5.3L block, just do it, just don't bore it .100 over and expect it to hold 600hp.

Are you looking for someone to tell you its OK to run the 5.3L block? You are not going to overpower any blocks.... unless you bore it .100 over

Buy the stupid 6.0L and just be done.
don't get me wrong. i appreciate the advice. i just wanted to know why i shouldn't go with the lm7 block. i know the 6.0 block is better, but i just wanted to get some perspective on the disadvantages of the 5.3l block. to answer your question, i'm going to be dumping money into this build and want to do it right the first time ... that's why i bumped it. just wanted a few more opinions.
Reply
Old Mar 14, 2009 | 08:25 PM
  #11  
Beaflag VonRathburg's Avatar
OWN3D BY MY PROF!
iTrader: (176)
 
Joined: Feb 2006
Posts: 9,146
Likes: 3
From: Jax Beach, Florida
Default

Another downside to the 5.3 at least where I am is the place we use charges you for two hones to take a 5.3 to 5.7. If you are going to add the weight of the iron block go with the 6.0 block.
Reply
Old Mar 14, 2009 | 08:39 PM
  #12  
custm2500's Avatar
Ph.D. in HUBRIS
iTrader: (11)
 
Joined: Mar 2009
Posts: 3,964
Likes: 0
Default

I don't see any posative to useing the 5.3 block. Punching it out so much is going weaken the block and make it compleatly unreliable! Just use the 6.0 block. I don't have a lot of time researching the 6.0 but (from what I have see) any tiny bit of knowledge about motors would tell you it just plain makes sence to go with the 6.0.
Reply
Old Mar 14, 2009 | 08:43 PM
  #13  
djsanchez2's Avatar
TECH Addict
iTrader: (14)
 
Joined: May 2005
Posts: 2,727
Likes: 0
From: Simi Valley, CA.
Default

Go 6.0 man, why even waste your time w/ the same motor of lower displacement?

5.3 stroked = 5.7
6.0 stroked = 6.68 liters. Gee which will make more power? (408), hell, bore only mini stroke on a 6.0 will still net more displacement on the stock crank. (370)
Reply
Old Mar 15, 2009 | 08:28 AM
  #14  
Beaflag VonRathburg's Avatar
OWN3D BY MY PROF!
iTrader: (176)
 
Joined: Feb 2006
Posts: 9,146
Likes: 3
From: Jax Beach, Florida
Default

You can still run a 5.3 honed to 5.7 reliably.We've done quite a few of them and we haven't had any problems.

A 5.3 has the same stroke as the LS1 3.622. If you stroke it works out to the same stroke. The only difference is the bore.
Reply




All times are GMT -5. The time now is 09:05 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