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Old 01-16-2008, 08:55 AM   #1
Super73
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Auto Gear Calculator

Not sure if anyone here will use this. But I stumbled a site that showed all the different gear ratios for the several transmisions. I threw it in an excel sheet and wrote some equations. Basically if you put in your Gear, Tire, Converter loss and RPM it will give you mph for both a locked and unlocked converter. Might be helpful to figure out what you need.

http://73-ls1.com/misc/gearing_revision_2.xls

If you have a tranny you would like me to add, post the gear specs and I'll add it.

Added RPM vs MPH in 100 rpm increments. Put your info in the first page labeled "Top Speed"

Last edited by Super73; 01-17-2008 at 10:35 PM.
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Old 01-16-2008, 08:56 AM   #2
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Re: Auto Gear Calculator

Sweet!
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Old 01-16-2008, 09:15 AM   #3
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Re: Auto Gear Calculator

Did you give it a try? Did it work?
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Old 01-16-2008, 09:28 AM   #4
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Re: Auto Gear Calculator

Yea...I did. Seems to be pretty close if not right on it.
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Old 10-25-2009, 02:06 AM   #5
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Re: Auto Gear Calculator

Thought this might be a good stcky for people trying to figure out gear ratios and converter slip..
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------Motor---------------Bottle
60'---1.53---------------1.41
1/8---6.58 @ 105.92----5.87 @ 118.41
1/4---10.38 @ 126.97----9.24 @ 142.49
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Old 02-27-2010, 11:33 PM   #6
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Re: Auto Gear Calculator

Good stuff. shows me shift points more clearly.
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Old 02-28-2010, 02:56 AM   #7
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Re: Auto Gear Calculator

hey super i need a richmond 5 speed added. what info do you need? just the first 1st through 5th ratios?
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Old 02-28-2010, 03:40 AM   #8
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Re: Auto Gear Calculator

1st through 5th ratios..
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------Motor---------------Bottle
60'---1.53---------------1.41
1/8---6.58 @ 105.92----5.87 @ 118.41
1/4---10.38 @ 126.97----9.24 @ 142.49
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Old 03-14-2010, 03:03 PM   #9
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Re: Auto Gear Calculator

1st 3.28

2nd 2.13

3rd 1.57

4th 1.24

5th 1.00

sorry it took so long, put this on the back burner been so busy. i appreciate it though.
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Old 10-26-2010, 11:27 PM   #10
olay198912
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Re: Auto Gear Calculator

A gearing mechanism of a motor vehicle engine that reduces the power output required to maintain driving speed in a specific range by lowering the gear ratio

Last edited by olay198912; 10-26-2010 at 11:28 PM.
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Old 11-26-2010, 01:39 AM   #11
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Re: Auto Gear Calculator

Quote:
Originally Posted by olay198912 View Post
A gearing mechanism of a motor vehicle engine that reduces the power output required to maintain driving speed in a specific range by lowering the gear ratio


This is the third time I have read this on 3 different dates. Still trying to figure out what you are exactly looking for..
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------Motor---------------Bottle
60'---1.53---------------1.41
1/8---6.58 @ 105.92----5.87 @ 118.41
1/4---10.38 @ 126.97----9.24 @ 142.49
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Old 08-09-2011, 05:15 AM   #12
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Re: Auto Gear Calculator

Here's another link that you may or may not want to use.
http://www.grimmjeeper.com/gears.html

Enjoy!
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Old 02-02-2014, 11:44 PM   #13
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Re: Auto Gear Calculator

Hey super 73 this is a little off topic and im brand new to the website and it seems like you really know your stuff, i have a 69 shortbed with an 11-1 built 383 built 700r4 with hardened output shaft all the goodies lockup 3600 converter 3.42 rear gears and a 30 inch tall tire,truck weighs 3600 lbs i am wanting to switch to a 4.11 or 4.30 gear and didnt know if it would be too much gear for going through the traps in 3rd gear without shifting in to overdrive? any help would be great
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Old 04-01-2014, 08:34 AM   #14
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Re: Auto Gear Calculator

You do not want to be in OD unless you have really have that trans built to go there.. Very few are set to handle big power in OD. Plus the drop to

Drop to a 28 in tall tire. Cheaper to test that set up for RPM. what is max RPM on the engine? A few links with gear calc programs . A 30 inch tall tire in bias or radial?? Tire growth will come into play with a bais tire if that is what you have now, my dealings has been that tire is growing at least 1-1.5 inchs on the big end

Try this one..

http://hotrodworks.net/hotrodmath/quarter.html

http://www.locost7.info/gearcalc.php
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