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

SCR effect on DCR

Old Oct 12, 2013 | 01:45 PM
  #1  
redtan's Avatar
Thread Starter
TECH Junkie
iTrader: (5)
 
Joined: May 2008
Posts: 3,764
Likes: 17
From: Belmont, MA
Default SCR effect on DCR

Does the static compression ratio make a difference in the dynamic compression ratio or are they completely separate from eachother?

I ask this because I'm using a DCR calculator from I believe a guy called pianoprodigy. Using the OEM settings for my engine and the camshaft I'm running and I get 8.65 DCR...cool.

But then when I go change the headgasket thickness to say 0.040 to increase the SCR, the DCR also goes up even tho the cam specs remained exactly the same.
Reply
Old Oct 12, 2013 | 01:54 PM
  #2  
poltergeist 02's Avatar
TECH Fanatic
10 Year Member
iTrader: (65)
 
Joined: Jan 2010
Posts: 1,402
Likes: 3
Default

yes SCR effects DCR. From what I have read 8.5 DCR is a good number to shoot for if running pump gas.
Reply
Old Oct 12, 2013 | 02:04 PM
  #3  
redtan's Avatar
Thread Starter
TECH Junkie
iTrader: (5)
 
Joined: May 2008
Posts: 3,764
Likes: 17
From: Belmont, MA
Default

yes SCR effects DCR
Dang then I need to re-think my camshaft selection completely. I've been using the DCR calculator independently of the SCR info and came up with a cam that gave me around 8.6 DCR with 10.9 SCR. But with 11.5 SCR the DCR jumped to 9.1

Does that make sense that it would jump that much?
Reply
Old Oct 12, 2013 | 02:54 PM
  #4  
99Bluz28's Avatar
TECH Senior Member
iTrader: (35)
 
Joined: Nov 2007
Posts: 9,705
Likes: 11
From: C. V., Kalifornia
Default

That doesn't sound right at all.
It should only be about 1/3 of a point increase in SCR, and about 1/4 point increase in DCR with that change to a .04" gasket; at least for a LS1 motor.
Reply
Old Oct 12, 2013 | 02:58 PM
  #5  
redtan's Avatar
Thread Starter
TECH Junkie
iTrader: (5)
 
Joined: May 2008
Posts: 3,764
Likes: 17
From: Belmont, MA
Default

It's an LS2, going from 10.9 to 11.5 with milled heads and 0.040 gaskets.

A 226/234 cam with IVC 40* comes up with 8.6 DCR on stock compression.

The same cam comes up with 9.1 DCR on 11.5 compression.

Maybe I'm just using the wrong calculator.
Reply
Old Oct 12, 2013 | 03:15 PM
  #6  
99Bluz28's Avatar
TECH Senior Member
iTrader: (35)
 
Joined: Nov 2007
Posts: 9,705
Likes: 11
From: C. V., Kalifornia
Default

If you retard the cam about 4* for your current ICL it'll drop the DCR back down to about 8.65. The possible down side is that it'll shift the power band up about 300-400 rpm. Now if you want to shift the powerband up higher then that's a plus.
Reply
Old Oct 12, 2013 | 04:54 PM
  #7  
redtan's Avatar
Thread Starter
TECH Junkie
iTrader: (5)
 
Joined: May 2008
Posts: 3,764
Likes: 17
From: Belmont, MA
Default

Yeah that's probably what I'll end up doing, just wanted to make sure that it sounded correct before I go and change the cam specs.
Reply


Thread Tools
Search this Thread

All times are GMT -5. The time now is 12:34 PM.

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