RearEnd Ratio - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



Register FAQ Search Today's Posts Unanswered Posts Auto Escrow Insurance Auto Loans Advertise
Hot Rod Forum : Hotrodders Bulletin Board > Tech Help> Hotrodding Basics
User Name
Password
lost password?   |   register now

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 02-11-2011, 07:35 AM
Registered User
 
Join Date: Oct 2009
Location: Marietta, Ga
Posts: 24
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
RearEnd Ratio

Any ideas on a good rear end Ration for a hemi engine, 545RFE 5 speed?

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 02-11-2011, 08:03 AM
Registered User
 
Last wiki edit: Mopar tapered axle rear brake conversion
Last journal entry: What I'm doing now...
Join Date: Jan 2002
Posts: 4,259
Wiki Edits: 49

Thanks: 0
Thanked 9 Times in 8 Posts
Which one: 241, 259, 270, 276, 291, 315, 325, 330, 331, 341, 345, 354, 392, 426, 5.7, or 6.1 ?? It makes a difference and also it depends on what you want to do with the car. Cruiser, weekend bracket racer, Pro-street??? We need a little more information before anyone can give you an intelligent answer.

Centerline
HotRodsAndHemis.com

"If your wife wants to learn to drive, don't stand in her way." - Sam Levenson
Reply With Quote Quick reply to this message
  #3 (permalink)  
Old 02-11-2011, 08:08 AM
Registered User
 
Join Date: Oct 2009
Location: Marietta, Ga
Posts: 24
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Hemi 5.7 attached to 5 speed 545RFE. Cruise.
Reply With Quote Quick reply to this message
 
  #4 (permalink)  
Old 02-11-2011, 08:46 AM
sqzbox's Avatar
My pipes are my music
 
Join Date: Sep 2009
Location: indiana
Age: 70
Posts: 2,936
Wiki Edits: 0

Thanks: 0
Thanked 3 Times in 3 Posts
3:91:1 Dana and a good free flowing exhaust system.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 02-11-2011, 09:04 AM
Registered User
 
Join Date: Oct 2009
Location: Marietta, Ga
Posts: 24
Wiki Edits: 0

Thanks: 0
Thanked 0 Times in 0 Posts
Great answer, I was hoping for something like that.
Reply With Quote Quick reply to this message
  #6 (permalink)  
Old 02-11-2011, 09:17 AM
sqzbox's Avatar
My pipes are my music
 
Join Date: Sep 2009
Location: indiana
Age: 70
Posts: 2,936
Wiki Edits: 0

Thanks: 0
Thanked 3 Times in 3 Posts
Yeah, we'll see how long this lasts. Someone always trumps me on this cause I'm so "old school".
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 02-11-2011, 09:32 AM
1ownerT's Avatar
Home School Valedictorian
 
Last wiki edit: Health and safety in the shop or garage
Join Date: Dec 2004
Location: Iowa
Age: 59
Posts: 1,639
Wiki Edits: 4

Thanks: 0
Thanked 3 Times in 3 Posts
With the .67 overdrive ratio of that trans, a 3.91/3.92 would have an effective ratio of 2.67 in OD at cruise.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 02-11-2011, 09:43 AM
Valkyrie5.7's Avatar
www.generationhighoutput. com
 
Last wiki edit: Painting chrome wheels
Last journal entry: Stopping my journal entries here
Join Date: Feb 2010
Location: Phoenix
Age: 33
Posts: 897
Wiki Edits: 15

Thanks: 147
Thanked 72 Times in 63 Posts
Quote:
Originally Posted by sqzbox
Yeah, we'll see how long this lasts. Someone always trumps me on this cause I'm so "old school".
Nothing wrong with being "old school". I happen to agree with you. The steep first gear and light overdrive makes a 3.91 gear fun for the seat of the pants without tugging on the wallet in the back pocket. It'll definitely get off the line in a hurry
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 02-11-2011, 09:43 AM
big gear head's Avatar
High Performance Rear Ends
 
Join Date: Nov 2009
Location: Central City, KY
Posts: 3,561
Wiki Edits: 0

Thanks: 89
Thanked 1,786 Times in 1,342 Posts
How tall are the rear tires? What rear end are you using?
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 02-11-2011, 10:04 AM
Registered User
 
Last wiki edit: Mopar tapered axle rear brake conversion
Last journal entry: What I'm doing now...
Join Date: Jan 2002
Posts: 4,259
Wiki Edits: 49

Thanks: 0
Thanked 9 Times in 8 Posts
OK 5.7 ltr. You're not going to be limited in rpm, torque or hp as you would with some of the early hemis.

I would use one of the rpm calculators like this one RPM Calculator to determine what gear set to use. You'll need to know what tire size you're going to run and then just plug in the variables in order to wind up with a cruise rpm of 1600 -1800 rpm (which is a comfortable RPM for the 5.7 ltr.) at 70 mph. My guess, if you run 31" - 33" tires you're looking at around a 3:50 gear set given the .67 overdrive of that trans.

Centerline
HotRodsAndHemis.com

"Remember, if you didn't put it together with your own hands, its not really yours." - Tim Allen
Reply With Quote Quick reply to this message

Recent Hotrodding Basics posts with photos

Quick Reply
Message:
Options

Register Now

In order to be able to post messages on the Hot Rod Forum : Hotrodders Bulletin Board forums, you must first register.
Please enter your desired user name (usually not your first and last name), your email address and other required details in the form below.
User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.
Password:
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Insurance
Please select your insurance company (Optional)

Log-in



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

Posting Rules
You may post new threads
You may 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 Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
gear ratio rearend myownharley11anthony Engine 0 08-14-2010 08:06 PM
RearEnd Ratio 36 Chevy Guy Transmission - Rearend 1 07-29-2010 10:57 PM
rearend ratio yragat Transmission - Rearend 2 04-23-2008 07:30 AM
Confirming rearend ratio 3100 Special Transmission - Rearend 3 01-08-2006 03:11 PM
How do you tell rearend Ratio Bluegrass Transmission - Rearend 14 12-26-2002 01:56 PM


All times are GMT -6. The time now is 01:42 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.