Gearing VS MPH - Hot Rod Forum : Hotrodders Bulletin Board
Hotrodders.com -- Hot Rod Forum



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

Reply
 
LinkBack Thread Tools
  #1 (permalink)  
Old 07-18-2013, 09:40 AM
Slammedsi's Avatar
Registered User
 
Last photo:
Join Date: Feb 2013
Location: Vernon, TX
Posts: 298
Wiki Edits: 0

Thanks: 132
Thanked 5 Times in 5 Posts
Gearing VS MPH

I am going to change out my rear gearing to something in the 4.00 range. I was wanting to know if there is a calculator that will show what my top speed in each gear will be at 6000 rpm? Ive Googled and didn't find much. Im running a 700R4 trans and wanting to know the different mph for say a 4.10,4.56, and 4.88. Factory 700R4 gearing is 3.59:1, 1.625:1, 1.0:1, and 0.696:1. I will be running a 30.10 inch tall tire. Any help would be great.

    Advertisement
Reply With Quote Quick reply to this message
Sponsored Links
Advertisement
 
  #2 (permalink)  
Old 07-18-2013, 10:20 AM
hrlys4evr's Avatar
60-66 chevy truck nut
 

Last journal entry: Hood finally in paint
Last photo:
Join Date: Feb 2008
Location: Chula Vista, CA.
Age: 39
Posts: 41
Wiki Edits: 0

Thanks: 5
Thanked 3 Times in 3 Posts
Gear Ratios Calculator, MPH, Top Speed - DragTimes.com

Try this out.

Chris
Reply With Quote Quick reply to this message
The Following User Says Thank You to hrlys4evr For This Useful Post:
Slammedsi (07-18-2013)
  #3 (permalink)  
Old 07-18-2013, 10:24 AM
Slammedsi's Avatar
Registered User
 
Last photo:
Join Date: Feb 2013
Location: Vernon, TX
Posts: 298
Wiki Edits: 0

Thanks: 132
Thanked 5 Times in 5 Posts
Quote:
Originally Posted by Slammedsi View Post
I am going to change out my rear gearing to something in the 4.00 range. I was wanting to know if there is a calculator that will show what my top speed in each gear will be at 6000 rpm? Ive Googled and didn't find much. Im running a 700R4 trans and wanting to know the different mph for say a 4.10,4.56, and 4.88. Factory 700R4 gearing is 3.59:1, 1.625:1, 1.0:1, and 0.696:1. I will be running a 30.10 inch tall tire. Any help would be great.
I had a friend give me a link that i believe gave me what I wanted to know. Tell me if this information sounds correct.

using a 3.73 and 700R4 @ 6000RPM

1st. 47mph
2nd. 89mph
3rd. 144mph
4th. 207mph

This information seems strange. There isn't a speed o in the truck at this time so i cant correlate this information.

Now going to a 4.88, 700R4 @ 6000RPM

1st. 36
2nd. 68
3rd. 110
4th. 158
Reply With Quote Quick reply to this message
  #4 (permalink)  
Old 07-18-2013, 10:30 AM
Slammedsi's Avatar
Registered User
 
Last photo:
Join Date: Feb 2013
Location: Vernon, TX
Posts: 298
Wiki Edits: 0

Thanks: 132
Thanked 5 Times in 5 Posts
Quote:
Originally Posted by hrlys4evr View Post
Now that one seems to be more accurate. The one I used first Showed way to high of a mph for first gear. For instance, the 47 mph in first. But the link you gave me shows a 40mph first using 3.73 rear end. Alot better.
Reply With Quote Quick reply to this message
  #5 (permalink)  
Old 07-18-2013, 10:45 AM
hrlys4evr's Avatar
60-66 chevy truck nut
 

Last journal entry: Hood finally in paint
Last photo:
Join Date: Feb 2008
Location: Chula Vista, CA.
Age: 39
Posts: 41
Wiki Edits: 0

Thanks: 5
Thanked 3 Times in 3 Posts
Yep. Looks right. You can bounce it off of TCI transmissions calculator also.

Last edited by hrlys4evr; 07-18-2013 at 10:56 AM.
Reply With Quote Quick reply to this message
The Following User Says Thank You to hrlys4evr For This Useful Post:
Slammedsi (07-18-2013)
  #6 (permalink)  
Old 07-18-2013, 11:43 AM
F-BIRD'88's Avatar
Yada Yada Yada
 
Last photo:
Join Date: Oct 2005
Location: Ontario, Canada
Posts: 9,153
Wiki Edits: 0

Thanks: 5
Thanked 380 Times in 374 Posts
RPM / gear ratio X rear tire diameter /336 ='s MPH

This is for when there is no torque converter slippage ( manual trans or converter locked up)

Use 355 instead of 336 for a typical stock converter and use 360 instead of 336 for a high stall.

Th700r4 gear ratios are 3.06 1.61 1.11 and .70 it is a 30% OD

The higher the rear ger ratio, the more profound the 30% taming effect when in OD (RPM reduction)
This trans is not designed to operate at full throttle when in OD. Its a cruising gear.

So when in OD, a 4.88:1 axle ratio gets tamed to 3.42:1 So don't be shy with the gear swap choice if you want this heavy truck to accelerate fast. Especially with the tall tires.
Reply With Quote Quick reply to this message
  #7 (permalink)  
Old 07-18-2013, 01:00 PM
Slammedsi's Avatar
Registered User
 
Last photo:
Join Date: Feb 2013
Location: Vernon, TX
Posts: 298
Wiki Edits: 0

Thanks: 132
Thanked 5 Times in 5 Posts
Quote:
Originally Posted by F-BIRD'88 View Post
RPM / gear ratio X rear tire diameter /336 ='s MPH

This is for when there is no torque converter slippage ( manual trans or converter locked up)

Use 355 instead of 336 for a typical stock converter and use 360 instead of 336 for a high stall.

Th700r4 gear ratios are 3.06 1.61 1.11 and .70 it is a 30% OD

The higher the rear ger ratio, the more profound the 30% taming effect when in OD (RPM reduction)
This trans is not designed to operate at full throttle when in OD. Its a cruising gear.

So when in OD, a 4.88:1 axle ratio gets tamed to 3.42:1 So don't be shy with the gear swap choice if you want this heavy truck to accelerate fast. Especially with the tall tires.
Using your math I come up with a 102.8mph. Is this the theritical top speed, Seems offly low.
Reply With Quote Quick reply to this message
  #8 (permalink)  
Old 07-18-2013, 01:10 PM
Slammedsi's Avatar
Registered User
 
Last photo:
Join Date: Feb 2013
Location: Vernon, TX
Posts: 298
Wiki Edits: 0

Thanks: 132
Thanked 5 Times in 5 Posts
Quote:
Originally Posted by F-BIRD'88 View Post
RPM / gear ratio X rear tire diameter /336 ='s MPH

This is for when there is no torque converter slippage ( manual trans or converter locked up)

Use 355 instead of 336 for a typical stock converter and use 360 instead of 336 for a high stall.

Th700r4 gear ratios are 3.06 1.61 1.11 and .70 it is a 30% OD

The higher the rear ger ratio, the more profound the 30% taming effect when in OD (RPM reduction)
This trans is not designed to operate at full throttle when in OD. Its a cruising gear.

So when in OD, a 4.88:1 axle ratio gets tamed to 3.42:1 So don't be shy with the gear swap choice if you want this heavy truck to accelerate fast. Especially with the tall tires.
Using your math I come up with a 102.8mph. Is this the theritical top speed, Seems offly low.
Reply With Quote Quick reply to this message
  #9 (permalink)  
Old 07-18-2013, 01:26 PM
Slammedsi's Avatar
Registered User
 
Last photo:
Join Date: Feb 2013
Location: Vernon, TX
Posts: 298
Wiki Edits: 0

Thanks: 132
Thanked 5 Times in 5 Posts
Quote:
Originally Posted by F-BIRD'88 View Post
RPM / gear ratio X rear tire diameter /336 ='s MPH

This is for when there is no torque converter slippage ( manual trans or converter locked up)

Use 355 instead of 336 for a typical stock converter and use 360 instead of 336 for a high stall.

Th700r4 gear ratios are 3.06 1.61 1.11 and .70 it is a 30% OD

The higher the rear ger ratio, the more profound the 30% taming effect when in OD (RPM reduction)
This trans is not designed to operate at full throttle when in OD. Its a cruising gear.

So when in OD, a 4.88:1 axle ratio gets tamed to 3.42:1 So don't be shy with the gear swap choice if you want this heavy truck to accelerate fast. Especially with the tall tires.
Using your math I come up with a 102.8mph. Is this the theritical top speed, Seems offly low.
Reply With Quote Quick reply to this message
  #10 (permalink)  
Old 07-18-2013, 02:12 PM
F-BIRD'88's Avatar
Yada Yada Yada
 
Last photo:
Join Date: Oct 2005
Location: Ontario, Canada
Posts: 9,153
Wiki Edits: 0

Thanks: 5
Thanked 380 Times in 374 Posts
Low for what? 1/4mile,,,keep your foot in it, it will rev thru the traps.
You don;t have much engine power and a heavy truck,, the trap rpm is not going to be very high.

Cruise,, That is what overdrive is for. You just cannot do it @ full WOT with that transmission.

how fast do you really think this truck will go go with the available power.? Top speed.

If you want it to accelerate you need a big lever to move it ( gear ratio)
The more you cam up the motor the higher the engine power/torque range (rpm), the higher you have to rev it
the more critical the rear gear ratio.

Go to the drag strip..FInd out how much real engine horsepower you really got to work with there.
Weight your truck its that simple.
Reply With Quote Quick reply to this message
  #11 (permalink)  
Old 07-18-2013, 02:18 PM
F-BIRD'88's Avatar
Yada Yada Yada
 
Last photo:
Join Date: Oct 2005
Location: Ontario, Canada
Posts: 9,153
Wiki Edits: 0

Thanks: 5
Thanked 380 Times in 374 Posts
In this 4000# truck with 30" tires and 4.88 gears you can hiway cruise fine @ 80MPH in OD @ a comfy 3000 rpm. You are not running Bonneville.

WOT in D (3rd gear) drive it will be reving 6440 @ 110MPH. You will need 500 real engine horsepower to do this.

110 MPH trap speed will run a very low 12sec Q mile

A blower on your 350

WOT @102.8MPH you need 402 real horsepower to hit this in 1/4mile ( low 13's)

Got 402 real engine horsepower?

Misprint on my th700r4 trans gear ratio's 3.06 1.61 1.00 .70 OD is 30% (.70:1)

This assumes your truck and you in it weight #4000 . it probably weights even more than this.
Trucks are heavy.

Last edited by F-BIRD'88; 07-18-2013 at 02:36 PM.
Reply With Quote Quick reply to this message
The Following User Says Thank You to F-BIRD'88 For This Useful Post:
Slammedsi (07-18-2013)
  #12 (permalink)  
Old 07-18-2013, 04:57 PM
Slammedsi's Avatar
Registered User
 
Last photo:
Join Date: Feb 2013
Location: Vernon, TX
Posts: 298
Wiki Edits: 0

Thanks: 132
Thanked 5 Times in 5 Posts
Quote:
Originally Posted by F-BIRD'88 View Post
In this 4000# truck with 30" tires and 4.88 gears you can hiway cruise fine @ 80MPH in OD @ a comfy 3000 rpm. You are not running Bonneville.

WOT in D (3rd gear) drive it will be reving 6440 @ 110MPH. You will need 500 real engine horsepower to do this.

110 MPH trap speed will run a very low 12sec Q mile

A blower on your 350

WOT @102.8MPH you need 402 real horsepower to hit this in 1/4mile ( low 13's)

Got 402 real engine horsepower?

Misprint on my th700r4 trans gear ratio's 3.06 1.61 1.00 .70 OD is 30% (.70:1)

This assumes your truck and you in it weight #4000 . it probably weights even more than this.
Trucks are heavy.
Truck weighs 3720 with me in it.
Reply With Quote Quick reply to this message
  #13 (permalink)  
Old 07-18-2013, 08:50 PM
vinniekq2's Avatar
Registered User
 
Join Date: Jun 2012
Location: BC,Canada
Age: 56
Posts: 8,330
Wiki Edits: 0

Thanks: 342
Thanked 814 Times in 780 Posts
Gear Ratio Speed Calculator

this is easy to use and different RPMs can be subbed in easy
Reply With Quote Quick reply to this message
The Following User Says Thank You to vinniekq2 For This Useful Post:
Slammedsi (07-19-2013)
  #14 (permalink)  
Old 07-19-2013, 07:49 AM
cobalt327's Avatar
WFO
 
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Location: Atlanta
Age: 59
Posts: 5,037
Wiki Edits: 1616

Thanks: 128
Thanked 597 Times in 546 Posts
Quote:
Originally Posted by Slammedsi View Post
I am going to change out my rear gearing to something in the 4.00 range. I was wanting to know if there is a calculator that will show what my top speed in each gear will be at 6000 rpm? Ive Googled and didn't find much. Im running a 700R4 trans and wanting to know the different mph for say a 4.10,4.56, and 4.88. Factory 700R4 gearing is 3.59:1, 1.625:1, 1.0:1, and 0.696:1. I will be running a 30.10 inch tall tire. Any help would be great.
Various Calculators from Wallace Racing
Reply With Quote Quick reply to this message
The Following User Says Thank You to cobalt327 For This Useful Post:
Slammedsi (07-19-2013)
  #15 (permalink)  
Old 07-19-2013, 09:56 AM
Slammedsi's Avatar
Registered User
 
Last photo:
Join Date: Feb 2013
Location: Vernon, TX
Posts: 298
Wiki Edits: 0

Thanks: 132
Thanked 5 Times in 5 Posts
thanks guys! Yall got what i needed.
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:

Log-in

Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




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
gearing ssonny34@yahoo.com Transmission - Rearend 1 04-13-2009 08:51 PM
gearing 1cleanmav! Transmission - Rearend 7 01-25-2008 07:37 AM
gearing 59 f100 Transmission - Rearend 5 11-06-2005 05:19 PM
Gearing help 5.0Towncar Transmission - Rearend 9 06-24-2003 08:18 PM
Help with gearing 5.0Towncar Transmission - Rearend 0 06-23-2003 05:38 PM


All times are GMT -6. The time now is 07:34 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0 PL2
Copyright Hotrodders.com 1999 - 2012. All Rights Reserved.