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-   -   Auto Gear Calculator (https://67-72chevytrucks.com/vboard/showthread.php?t=274314)

Super73 01-16-2008 08:55 AM

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"

Outlaw72 01-16-2008 08:56 AM

Re: Auto Gear Calculator
 
Sweet!

Super73 01-16-2008 09:15 AM

Re: Auto Gear Calculator
 
Did you give it a try? Did it work?

Outlaw72 01-16-2008 09:28 AM

Re: Auto Gear Calculator
 
Yea...I did. Seems to be pretty close if not right on it.

Super73 10-25-2009 02:06 AM

Re: Auto Gear Calculator
 
Thought this might be a good stcky for people trying to figure out gear ratios and converter slip..

82Cecil 02-27-2010 11:33 PM

Re: Auto Gear Calculator
 
Good stuff. shows me shift points more clearly.

wheatlandbrawler 02-28-2010 02:56 AM

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?

Super73 02-28-2010 03:40 AM

Re: Auto Gear Calculator
 
1st through 5th ratios..

wheatlandbrawler 03-14-2010 03:03 PM

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.

olay198912 10-26-2010 11:27 PM

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

Super73 11-26-2010 01:39 AM

Re: Auto Gear Calculator
 
Quote:

Originally Posted by olay198912 (Post 4262591)
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..

1malo68 08-09-2011 05:15 AM

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

Enjoy!

69restomod 02-02-2014 11:44 PM

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

GMR-PERFORMANCE 04-01-2014 08:34 AM

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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