 
Main Menu
|
|
Nevada Classics
|
|
Advertise at CC
|
| 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 |
|
|
|
|
|
|
CC Advertisers
|
|
06-03-2014, 09:34 PM
|
 |
CC Member
|
|
|
Join Date: May 2004
Cobra Make, Engine: CSX6363
Posts: 180
|
|
Not Ranked
Another Speedometer gear selection question
After using the gear selection calculators I found on several different sites, the results recommend using either a 17, 18, or 19 tooth gear. My tires are Billboards and have a 85" circumference, the transmission is a TKO 600 transmission (assuming 7 tooth drive gear), and the rear-end ration is 3.31.
Any suggestions???
|
06-04-2014, 08:14 AM
|
 |
CC Member
|
|
|
Join Date: Mar 2000
Location: Des Moines,
IA
Cobra Make, Engine: Sold my beloved Shelby CSX 4068, Gessford 427 Ford
Posts: 756
|
|
Not Ranked
Mike
Do you have a GPS? Garmin or similar? If so, take it for a short drive and document the difference between the indicated speed on the GPS vs your speedo.
It's simply a proportion to calculate which gear to use. If you're off by 10 percent, them substitute a gear with 10 percent more or less teeth to correct. More teeth slow it down, less teeth speed it up.
Let us know how it goes.
Doug
__________________
CSX4068, '69 Bronco, '70 BOSS 302, '87 Mustang GT, '08 Roush Trak Pak
|
06-04-2014, 08:57 AM
|
|
CC Member
|
|
|
Join Date: Apr 2013
Location: Redding,
CA
Cobra Make, Engine: 1966 Classic Roadster
Posts: 192
|
|
Not Ranked
If you don't have a GPS etc you can download a free app on your cell phone (smart phone). Thats what I did and it works great.
|
06-04-2014, 10:37 AM
|
|
CC Member
|
|
|
Join Date: Apr 2012
Location: Bay Area (Peninsula),
CA
Cobra Make, Engine: ERA 427, 427/487 side-oiler
Posts: 1,248
|
|
Not Ranked
I also used a few free iPhone GPS programs to calibrate my speedo and select gears. I think I ended up with a 20 tooth gear.
|
06-04-2014, 11:38 AM
|
|
CC Member
|
|
|
Join Date: May 2004
Cobra Make, Engine: CSX6363
Posts: 180
|
|
Not Ranked
I left out one important fact; the car is about 98% complete. This weekend I'm installing the speedo cable with the reverse gear box along along with a few things in the interior, then the car will be ready for the alignment shop.
I'm planning on ordering the speedo gear today but wanted to avoid buying two or three. If I had to select just one, I'd go with the 19 tooth (pink).
Doug, I know you have BBs and a TKO trans so do you recall which gear you have?
Edit: forgot to ask what rear-end ratio is in your car.
|
06-04-2014, 03:40 PM
|
|
CC Member
|
|
|
Join Date: Jan 2014
Location: Dallas,
TX
Cobra Make, Engine: Backdraft, Roush 342r
Posts: 17
|
|
Not Ranked
Order a SpeedHut GPS run speedo and there is no need to worry about the gearing or tire diameters. They have a reverse speedo for about $300.
|
06-04-2014, 06:20 PM
|
|
CC Member
|
|
|
Join Date: May 2004
Cobra Make, Engine: CSX6363
Posts: 180
|
|
Not Ranked
I have heard of GPS speedos and appreciate the info, but I already have the cable and the reverse gear box. It would be really cool to have the GPS technology in the car, but I'd like to keep the speedometer that came with the car. So, do I go with the pink gear or something else?
|
06-05-2014, 06:59 AM
|
 |
Senior Club Cobra Member
|
|
|
Join Date: May 2001
Location: Florence,
AL
Cobra Make, Engine: RCR GT 40 & 1966 Fairlane 390 5 speed
Posts: 4,511
|
|
Not Ranked
The calculator that I used called for a 17 tooth if the drive gear is a 7 tooth.
Dwight
__________________
''Life's tough.....it's even tougher if you're stupid.'' ~ John Wayne
"Happiness Is A Belt-Fed Weapon"
life's goal should be; "to be smarter than inanimate objects"
|
06-05-2014, 08:31 AM
|
|
CC Member
|
|
|
Join Date: Mar 2000
Location: Des Moines,
IA
Cobra Make, Engine: Sold my beloved Shelby CSX 4068, Gessford 427 Ford
Posts: 756
|
|
Not Ranked
Mike
I'm running a 21 tooth gear right now and it's still a bit off.
You may have to just pick one and go with it. The gears aren't expensive - buy the one you calculate to work and one or two extras with more and less teeth. It's only about a 10-minute job to switch the gears.
__________________
CSX4068, '69 Bronco, '70 BOSS 302, '87 Mustang GT, '08 Roush Trak Pak
|
Posting Rules
|
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts
HTML code is Off
|
|
|
All times are GMT -7. The time now is 07:31 AM.
Links monetized by VigLink
|
Linear Mode
