Go Back   Ford Truck Enthusiasts Forums > Performance, Engines & Troubleshooting > Performance & General Engine Building
Sign in using an external account
Register Forgot Password?


Welcome to Ford-Trucks Forums!
Welcome to Ford-Trucks.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Ford-Trucks Forums community today!





 
Reply
 
 
 
 
LinkBack Thread Tools Search this Thread
  #1  
Old 08-26-2014, 01:16 PM
mtntop1 mtntop1 is offline
Senior User
 
Join Date: May 2005
Posts: 121
mtntop1 is starting off with a positive reputation.
Cubic Inches

If I bore a 302cu in .30 over what will the new cubic inches be. Also approximately how much torque improvement.
Reply With Quote
  #2  
Old 08-26-2014, 02:06 PM
85e150six4mtod 85e150six4mtod is offline
Post Fiend
 
Join Date: Apr 2004
Posts: 16,033
85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation
That gives you a 306 and probably no measurable difference in power. You gain 4 CI, but you lose just a tick of compression.

Is this just a clean up bore during a rebuild?

http://www.wallaceracing.com/cid.php
Reply With Quote
  #3  
Old 08-26-2014, 04:46 PM
xlt4wd90 xlt4wd90 is online now
Postmaster
 
Join Date: Sep 2003
Posts: 4,493
xlt4wd90 is gaining momentum as a positive member of FTE.
Wouldn't boring out the cylinder GAIN a tick of compression? It's squeezing a little more volume into the same combustion chamber.
Reply With Quote
  #4  
Old 08-27-2014, 12:40 AM
85e150six4mtod 85e150six4mtod is offline
Post Fiend
 
Join Date: Apr 2004
Posts: 16,033
85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation
Bigger space and VE is not 100%. Marginal VE is even lower. Plus you usually have a bigger head gasket gap.
Reply With Quote
  #5  
Old 08-28-2014, 11:07 PM
SDDL-UP SDDL-UP is offline
Senior User
 
Join Date: Sep 2013
Location: North Idaho
Posts: 113
SDDL-UP is starting off with a positive reputation.
Yes, you gain compression by increasing the bore.
Reply With Quote
  #6  
Old 08-29-2014, 12:39 AM
85e150six4mtod 85e150six4mtod is offline
Post Fiend
 
Join Date: Apr 2004
Posts: 16,033
85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation85e150six4mtod has a superb reputation
Checked a couple of static CR calculators. You are correct, you get a bit of a boost in CR with a bigger bore, all else being the same.

Dynamic compression....not sure, but given the marginal volumetric efficiency, I don't see how you gain cylinder pressure while running. I suppose there is a standard, known calculation for that as well, but I don't feel like looking it up and proving myself wrong again.

Op hasn't been back yet.....
Reply With Quote
Old 08-29-2014, 12:39 AM
 
 
 
Reply

Go Back   Ford Truck Enthusiasts Forums > Performance, Engines & Troubleshooting > Performance & General Engine Building

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Add 2 cylinders to the 6.2....... MitchPeters 6.2L V8 1 07-22-2014 09:56 PM
There’s No Replacement For Displacement: 10,000 Cubic Inch Enterprise DSG-36 Diesel Fires Right Up A spongecop General Diesel Discussion 2 09-10-2013 05:33 PM
engine number help needed nineteen sixt5 1961 - 1966 F-100 & Larger F-Series Trucks 16 06-19-2013 10:13 PM
convert 6.4 L to cubic inches emayes2000 6.4L Power Stroke Diesel 12 09-02-2012 03:44 PM
do smaller engines make more torque per cubic inch than larger engines? Huntersbo Performance & General Engine Building 8 08-03-2012 07:31 PM



All times are GMT -5. The time now is 05:32 PM.


Powered by vBulletin® Version 3.8.7 AC1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Advertising - Terms of Use - Privacy Statement - Jobs
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. Ford® is a registered trademark of the Ford Motor Company.

vbulletin Admin Backup