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

Cometic thickness questions....

Thread Tools
 
Search this Thread
 
Old Jan 26, 2005 | 11:21 AM
  #1  
SPANKY LS1's Avatar
Thread Starter
TECH Junkie
20 Year Member
iTrader: (24)
 
Joined: Nov 2001
Posts: 3,490
Likes: 1
From: Seneca, SC
Default Cometic thickness questions....

Just wanted to verify that Cometics thickness is given compressed, right? A Cometic .040 is .040 compressed right?

Thanks, Shawn
Reply
Old Jan 26, 2005 | 11:33 AM
  #2  
jrp's Avatar
jrp
SN95 Director
20 Year Member
iTrader: (16)
 
Joined: Jul 2003
Posts: 10,755
Likes: 7
From: Valencia, Ca
Default

yes, the number stated is the compressed thickness. i went with the .045 cometic myself.
Reply
Old Jan 26, 2005 | 12:19 PM
  #3  
Slowhawk's Avatar
LS1Tech Sponsor
iTrader: (12)
 
Joined: Nov 2001
Posts: 14,865
Likes: 6
From: Bridgewater,Ma
Default

Yes it is.Just make sure you retorque them 3-4 times.Cometics can be a pain to compress right.I personally like the GM MLS's at .054.I've done the ultimate quench testing and there was no HP gain on the LS1's so I like spending $25 a gasket instead of $75-$100 per gasket for Cometics
Reply
Old Jan 26, 2005 | 12:27 PM
  #4  
Jimm's Avatar
Launching!
 
Joined: Oct 2003
Posts: 249
Likes: 0
From: Cary, NC/University Heights, OH
Default

Originally Posted by jrp
yes, the number stated is the compressed thickness. i went with the .045 cometic myself.
Reply
Old Jan 26, 2005 | 12:29 PM
  #5  
jrp's Avatar
jrp
SN95 Director
20 Year Member
iTrader: (16)
 
Joined: Jul 2003
Posts: 10,755
Likes: 7
From: Valencia, Ca
Default

Originally Posted by Slowhawk
Yes it is.Just make sure you retorque them 3-4 times.Cometics can be a pain to compress right.I personally like the GM MLS's at .054.I've done the ultimate quench testing and there was no HP gain on the LS1's so I like spending $25 a gasket instead of $75-$100 per gasket for Cometics
what was your retorqueing regiment? i torqued and retorqued mine during thee installation of my ARP studs. the engine hasnt been fired up yet, once broken in whats the retorqueing schedual?

and when your already thousands upon thousands into a project whats 75$ per gasket
Reply
Old Jan 26, 2005 | 02:21 PM
  #6  
HAMRHEAD's Avatar
10 Second Club
iTrader: (8)
 
Joined: Feb 2004
Posts: 2,846
Likes: 0
From: Milwaukee, WI
Default

I am curious as well.
Reply
Old Jan 26, 2005 | 02:32 PM
  #7  
RX-Ben's Avatar
TECH Apprentice
iTrader: (7)
 
Joined: Jun 2004
Posts: 372
Likes: 0
From: Brooklyn
Default

Quench doesn't give HP gains, it simply wards off detonation and allows higher static compression ratios and more timing.

Cometics are also reusable, from what I've read.

Ben
Reply
Old Jan 26, 2005 | 05:59 PM
  #8  
OnE Ls1 2 HaTe's Avatar
On The Tree
 
Joined: Jan 2005
Posts: 169
Likes: 0
From: Modesto, CA
Default

so then the cometics would be better for nitrous becuase of them warding off detonation?
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

 Brett Foote
story-1

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

 Pouria Savadkouei
story-2

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

 Verdad Gallardo
story-3

7 Most Reliable High-Performance Engines GM Has Ever Built

 Verdad Gallardo
story-4

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

 Verdad Gallardo
story-5

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

 Pouria Savadkouei
story-6

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

 Verdad Gallardo
story-7

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-8

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-9

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
Old Jan 26, 2005 | 06:28 PM
  #9  
crow2's Avatar
On The Tree
 
Joined: Jan 2005
Posts: 108
Likes: 0
Default

Originally Posted by SPANKY LS1
Just wanted to verify that Cometics thickness is given compressed, right? A Cometic .040 is .040 compressed right?

Thanks, Shawn
Just to touch on this~yes they are .040,you can also get .051"~or they can make you whatever you want reasonable per application.but .040 is the norm,or like .045 like some people like!great gaskets!
Reply
Old Jan 26, 2005 | 07:07 PM
  #10  
Slowhawk's Avatar
LS1Tech Sponsor
iTrader: (12)
 
Joined: Nov 2001
Posts: 14,865
Likes: 6
From: Bridgewater,Ma
Default

Originally Posted by jrp
what was your retorqueing regiment? i torqued and retorqued mine during thee installation of my ARP studs. the engine hasnt been fired up yet, once broken in whats the retorqueing schedual?

and when your already thousands upon thousands into a project whats 75$ per gasket
Go over the torque again before startup,then you should be fine. So far out of 4 motor's I put Cometics in,3 of them leaked.This was 2 years ago and I gave up with them.Now we just use MLS gaskets. 90% of our cars are running FI so we do stress these gaskets
Reply
Old Jan 26, 2005 | 07:14 PM
  #11  
Louis's Avatar
FormerVendor
iTrader: (7)
 
Joined: Nov 2001
Posts: 4,168
Likes: 2
From: Frisco/Wylie
Default

50+ Heads/cam jobs with the right mill and never a leak, Torqued twice.
Reply
Old Jan 26, 2005 | 07:21 PM
  #12  
mikey's Avatar
LS1TECH Sponsor
iTrader: (6)
 
Joined: Nov 2001
Posts: 2,102
Likes: 0
From: Reading, PA
Default

I use Cometic almost exclusively on my 400+ CI motors and not a problem but I use a bonding agent around the coolant passages. Cometic says no, I say yes The deck and head surfaces need to be perfectly smooth though. Never had a leak!

GM MLS gaskets do work better on 346 applications. They are a no-brainer.
Reply
Old Jan 26, 2005 | 07:31 PM
  #13  
pdd's Avatar
pdd
TECH Veteran
iTrader: (3)
 
Joined: Aug 2003
Posts: 4,156
Likes: 0
From: dudley mass
Default

Originally Posted by RX-Ben
Quench doesn't give HP gains, it simply wards off detonation and allows higher static compression ratios and more timing.

Cometics are also reusable, from what I've read.

Ben
i thought with the perfect quench, you gained more power guess id better torque down my cometics again
Reply
Old Jan 27, 2005 | 08:47 AM
  #14  
Mirek's Avatar
TECH Regular
 
Joined: Aug 2003
Posts: 414
Likes: 0
From: Berkley, MI
Default

Do you need to retorque with gm tty bolts too ?
Reply
Old Feb 1, 2005 | 09:34 AM
  #15  
crow2's Avatar
On The Tree
 
Joined: Jan 2005
Posts: 108
Likes: 0
Default

Originally Posted by Mirek
Do you need to retorque with gm tty bolts too ?
I did some checking for you on your question.According to GM,you do not re-torque the bolts.Retorque could affect the TTY bolts !
Reply
Old Feb 1, 2005 | 10:43 AM
  #16  
Mirek's Avatar
TECH Regular
 
Joined: Aug 2003
Posts: 414
Likes: 0
From: Berkley, MI
Default

Thanks Good looking out.
Reply




All times are GMT -5. The time now is 11:07 PM.

story-0
6 Gifts Neither Your Dad Nor Grad Will Shove Into the 'Trinket Drawer'

Don't get dad new socks or a grill brush this year.

By Brett Foote | 2026-06-09 14:55:56


VIEW MORE
story-1
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-2
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-3
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-4
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-5
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-6
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-7
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-8
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-9
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