SUPPORT OUR SPONSOR

Go Back   Club Cobra > Club Cobra Tech Areas > Shop Talk

Welcome to Club Cobra!  The World's largest non biased Shelby Cobra related site!

  •  » Representation from nearly all Cobra/Daytona/GT40 manufacturers
  •  » Help from all over the world for your questions
  •  » Build logs for you and all members
  •  » Blogs
  •  » Image Gallery
  •  » Many thousands of members and nearly 1 million posts! 

YES! I want to register an account for free right now!  p.s.: For registered members this ad will NOT show

MMG Superformance
Nevada Classics
Main Menu
Nevada Classics
Nevada Classics
Keith Craft Racing
Advertise at CC
Banner Ad Rates
MMG Superformance
MMG Superformance
March 2024
S M T W T F S
          1 2
3 4 5 6 7 8 9
10 11 12 13 14 15 16
17 18 19 20 21 22 23
24 25 26 27 28 29 30
31            
  #1 (permalink)  
Old 08-06-2005, 06:34 PM
CC Member
Visit my Photo Gallery

 
Join Date: Dec 2004
Location: toronto, ont
Cobra Make, Engine: 408w 500 h.p. 550 ft.lbs
Posts: 562
Not Ranked     
Question # of teeth

Anybody have a formula for calculating speedo gears???
I am using a T/L with a 8.8 rearend & a 3.2something gear..
How many teeth do I need on the speedo gear.

Craig

Sorry--- I'm using 295/50/r15 yokohama tires @ approx 27" tall

Thanks again

Craig

Last edited by cdnus; 08-06-2005 at 06:37 PM..
Reply With Quote
  #2 (permalink)  
Old 08-06-2005, 06:57 PM
Ibr8k4vetts's Avatar
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Jan 2001
Location: Santa Barbara, Ca., ca
Cobra Make, Engine: R.U.C.C. with a 427FE, toploader
Posts: 1,435
Not Ranked     
Default

try this,
http://www.4speedtoploaders.com/shop/enter.html
__________________
Mike Z
Nothing sucks more than that moment during an argument when you realize you’re wrong.
Reply With Quote
  #3 (permalink)  
Old 08-06-2005, 07:10 PM
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Jul 2002
Cobra Make, Engine:
Posts: 15,712
Not Ranked     
Default

I don't think David has an area on his web site to calculate the needed "tooth count" of the driven gear (speedo gear), which varies a lot. The "drive gear" on the output shaft also varies a lot in tooth count and size. It's complicated...

This MIGHT help:
http://www.sccoa.com/faq/speedgr.html

Once you get "in the ball park":
The number of teeth on your speedo gear is?
Your true speed compared to your speedometer reading is?
True speed is 50, speedo indicates 70?
Then the speedo gear is spinning to fast, gotta slow it down by adding more teeth. If you have 16 teeth, the maybe a 20 tooth gear would work? NOW we need a "math wizard"!

Last edited by Excaliber; 08-06-2005 at 07:33 PM..
Reply With Quote
  #4 (permalink)  
Old 08-06-2005, 07:23 PM
jwoodard's Avatar
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Aug 1999
Location: Carlsbad, CA
Cobra Make, Engine: Previous owner of SPF#1938, with a Keith Craft 496ci Genesis 427 side oiler, 667 FWHP, 633 FWTQ, 560 RWHP, 550 RWTQ.
Posts: 1,302
Not Ranked     
Smile Here's a page from...............

The Ford Racing Parts catalog with a speedometer gear usage chart.

http://www.fordracingparts.com/download/charts/129.pdf

__________________
Jim Woodard

Don't interfere with somethin' that ain't botherin' you none.
Reply With Quote
  #5 (permalink)  
Old 08-10-2005, 09:11 AM
CC Member
Visit my Photo Gallery

 
Join Date: Jun 2003
Cobra Make, Engine: ERA 427 w/496 Side Oiler, roller, dual quads
Posts: 417
Not Ranked     
Default

And yet another speedo site:
http://www.428cobrajet.com/speedo-calc.html
__________________
Do you know why they call it "PMS"? Because "Mad Cow Disease" was taken. --Unknown, presumed deceased
Reply With Quote
  #6 (permalink)  
Old 08-10-2005, 05:25 PM
CC Member
Visit my Photo Gallery

 
Join Date: Dec 2004
Location: toronto, ont
Cobra Make, Engine: 408w 500 h.p. 550 ft.lbs
Posts: 562
Not Ranked     
Default

Thanks everyone,
I am now able to work it out thanks to you guys & your info

Craig
Reply With Quote
Reply


Thread Tools
Display Modes

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



All times are GMT -7. The time now is 01:54 AM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
The representations expressed are the representations and opinions of the clubcobra.com forum members and do not necessarily reflect the opinions and viewpoints of the site owners, moderators, Shelby American, any other replica manufacturer, Ford Motor Company. This website has been planned and developed by clubcobra.com and its forum members and should not be construed as being endorsed by Ford Motor Company, or Shelby American or any other manufacturer unless expressly noted by that entity. "Cobra" and the Cobra logo are registered trademarks for Ford Motor Co., Inc. clubcobra.com forum members agree not to post any copyrighted material unless the copyrighted material is owned by you. Although we do not and cannot review the messages posted and are not responsible for the content of any of these messages, we reserve the right to delete any message for any reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold us harmless with respect to any claim based upon transmission of your message(s). Thank you for visiting clubcobra.com. For full policy documentation refer to the following link: CC Policy