Engine Mods Outrageous Builds, High-Horsepower Modifications, strokers, and big cams for the Corvette

engine math

Thread Tools
 
Search this Thread
 
Old May 14, 2003 | 05:18 PM
  #1  
Todbo's Avatar
Todbo
Thread Starter
Burning Brakes
 
Joined: May 2001
Posts: 988
Likes: 1
From: Dyersburg TN
Default engine math

can anyone post the formula for determining displacment in a bored over engine? Thanks
Reply
Old May 14, 2003 | 05:48 PM
  #2  
Chuck Harmon's Avatar
Chuck Harmon
Melting Slicks
25 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Apr 2000
Posts: 3,286
Likes: 8
From: San Jose California
Default Re: engine math (Todbo)

Pi x r squared x stroke x number of cylinders

i.e. 427 BB = 4.25" bore, 3.76" stroke

3.142 x ((4.25"/2)squared) x 3.76 = 53.347 cubic inches per cylinder

53.347 x 8 = 426.778 cubic inch engine displacement

Chuck
Reply
Old May 14, 2003 | 06:41 PM
  #3  
Todbo's Avatar
Todbo
Thread Starter
Burning Brakes
 
Joined: May 2001
Posts: 988
Likes: 1
From: Dyersburg TN
Default Re: engine math (Chuck Harmon)

Thanks Chuck , so if I want to figure the .040 over 427 I would replace the 4.250 with 4.29 in the formula and that would give me the corrected displacment. :cheers:
Reply
Old May 14, 2003 | 08:29 PM
  #4  
Chuck Harmon's Avatar
Chuck Harmon
Melting Slicks
25 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Apr 2000
Posts: 3,286
Likes: 8
From: San Jose California
Default Re: engine math (Todbo)

Yep, you got it. I hate to bore more than I need to, but increasing the bore (unlike stroking) does increase your horse power. "When in doubt, bore it out!"

Chuck
Reply
Old May 14, 2003 | 09:32 PM
  #5  
clem zahrobsky's Avatar
clem zahrobsky
Le Mans Master
10 Year Member
 
Joined: Mar 1999
Posts: 6,744
Likes: 1
From: delmont pa
Cruise-In I Veteran
Cruise-In II Veteran
Default Re: engine math (Todbo)

bore diameter X bore diameter X.7854 X stroke X 8 = CID
Reply
Old May 14, 2003 | 09:53 PM
  #6  
CFI-EFI's Avatar
CFI-EFI
Race Director
10 Year Member
 
Joined: Sep 2000
Posts: 17,298
Likes: 33
From: The Top of Utah
Default Re: engine math (Chuck Harmon)

Pi X [rXr] X stroke X no cyl.= CID

bore diameter X bore diameter X.7854 X stroke X no cyl = CID

These are both valid formulae for the volume of a cylinder (engine, w/X no cyls.). I remember the pi X r version from 8th grade geometry. The volume equals the area of the base times the height.

Yep, you got it. I hate to bore more than I need to, but increasing the bore (unlike stroking) does increase your horse power
Chuck
HUH???

RACE ON!!!
1984 Crossfire
Member NHRA
Reply
Old May 14, 2003 | 10:17 PM
  #7  
clem zahrobsky's Avatar
clem zahrobsky
Le Mans Master
10 Year Member
 
Joined: Mar 1999
Posts: 6,744
Likes: 1
From: delmont pa
Cruise-In I Veteran
Cruise-In II Veteran
Default Re: engine math (CFI-EFI)

nhra and nascar use the bore x bore x.7854 x stroke x number of clys to determine the displacement. :chevy
Reply
Old May 23, 2003 | 03:18 AM
  #8  
blackLS1's Avatar
blackLS1
Racer
 
Joined: Jan 2002
Posts: 440
Likes: 2
From: Smithfield NC
Default Re: engine math (clem zahrobsky)

What about to determine CR?You go by the deck hight and pistons and combustion area of the heads correct?But what would the formula be?
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

 Joe Kucinski
story-1

8 Coolest Corvette Pace Cars (and Replicas) of All Time

 Verdad Gallardo
story-2

Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

 Joe Kucinski
story-3

Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

 Verdad Gallardo
story-4

Top 10 Corvettes Coming to Mecum Indy 2026!

 Brett Foote
story-5

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-6

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-7

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-8

2027 Corvette vs The World: Every C8 vs Its Closest Competitor

 Joe Kucinski
story-9

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
Old May 23, 2003 | 11:40 AM
  #9  
clem zahrobsky's Avatar
clem zahrobsky
Le Mans Master
10 Year Member
 
Joined: Mar 1999
Posts: 6,744
Likes: 1
From: delmont pa
Cruise-In I Veteran
Cruise-In II Veteran
Default Re: engine math (blackLS1)

go to http://cochise.uia.net/pkelley2/crc.htm :chevy
Reply

Get notified of new replies

To engine math





All times are GMT -4. The time now is 04:30 AM.

story-0
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-1
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE
story-2
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)

Slideshow: Ranking the top 10 Corvette engines by torque output.

By Joe Kucinski | 2026-05-05 11:58:09


VIEW MORE
story-3
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!

Slideshow: A Corvette pace car nearly matching IndyCar speeds sounds exaggerated, until you look at the numbers.

By Verdad Gallardo | 2026-05-04 20:03:36


VIEW MORE
story-4
Top 10 Corvettes Coming to Mecum Indy 2026!

Among a rather large group of them.

By Brett Foote | 2026-05-04 13:56:44


VIEW MORE
story-5
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-6
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-7
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-8
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-9
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE