|
#1
|
|||
|
|||
speedo pinion gear
can someone help me here? i have a 69 charger with 4:10's. it has p255/60/r15's on it. my book said that 15 inch tires came with the 426 only. the speedo didn't work when bought, so i replaced the gear with a new one, same 32 tooth, this is wrong because it apple cored, nothing works. i've read the forums, found the pinion chart. now the 4:10 uses a 40 ta 43 tooth, how do i get the right gear?
thanks 69 baby < happy moparing |
#2
|
||||
|
||||
Straight from my post that is in the Tech Archives http://www.moparchat.com/forums/show...&postid=372505
Quote:
|
#3
|
||||
|
||||
Here's the simple spreadsheet. Just input the tire diameter and the axle ratio and it will give you the number of teeth for the pinion gear.
I had to make it into a .zip file as the site won't let me upload an xls file. |
#4
|
|||
|
|||
By "apple cored" do you mean it sheared the teeth off of the plastic gear? If so, the gear wasn't indexed correctly.
The correct gear for this setup is a 40 tooth (current P/N is 52068062) and the adapter in the tailhousing must be installed with the hash mark next to the tooth count aligned with the raised dot on the tailhousing. See pic below. |
#5
|
|||
|
|||
Ehostler, I'm trying your formula but don't understand exactly what it is. What is the little star for? Sorry for being such a dunce-could you maybe put it in english rather than the math formula version? Thanks.....djs
|
#6
|
|||
|
|||
speedo pinion
they say theres no dumb questions, but i sure feel like an idiot.
i down loaded the zip but my puter didn't like it. i went back to all the forums i could get and couldn't make heads or tails of them. by apple cored it looks like you ate an apple, outside edges full, the middle narrow. thats the way the one i was replacing looked like too. i installed it the way the manual said. with the "proper tooth range number 6 o'clock carefully press into housing" put retainer in slots tap and tighten bolt. if 40 is what i need how did you get it? thanks for all your help!!!! pvanlannen@excel.net lost but not forgotten again thanks 69 baby happy moparing |
#7
|
|||
|
|||
The gears can be purchased from the dealers, some of the counter jocks can give you the correct setup for your application. They are even more helpful if you point them in the right direction.
|
#8
|
||||
|
||||
Quote:
For a regular calculator or for those doing this in pencil - ((63360/tire circumference) X gear ratio)/76.3 = number of speedometer gear teeth tire circumference = tire diameter X PI(3.14159) |
#9
|
|||
|
|||
Thanks Ehostler for the clarification. It all works out now. ....djs
|
#10
|
|||
|
|||
thanks again but it's not working for me.
69 baby happy moparing |
#11
|
|||
|
|||
69baby; try this. divide 63360 by the circumference of your tire. You can figure out the circumference one of two ways. Measure the height of the tire, lets say 28 ", then multiply by 3.1416. The answer is 87.96. To verify, wrap a piece of string around the tire, mark it where the ends meet, then lay it out and use a tape to measure. Take that figure (720.32) and multiply by your diff gear ratio,(lets say 3.55). The answer to that is 2,557.16. Divide by 76.3, the answer is 33.51. Now round up to the next whole number which is 34, and thats the number of teeth needed for your speedo drive gear. Hope this helps you..................djs
|
#12
|
|||
|
|||
Hi again all,
Thanks again. I did the math, and guess what it works. I don't know what I was doing wrong, I went back and did the math from both of you and got the same answer. Maybe I was just trying to hard. I ordered parts today and I feel better now. I will keep this formula for future reference. I off to my next project, electronic ignition upgrade. 69 baby Happy Moparing! |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
Speedo Pinion seal | bwlizard | Performance Talk | 3 | 07-06-2006 07:34 PM |
Speedo Pinion Gear Replacement | DavidA | Performance Talk | 3 | 05-17-2006 05:43 AM |
33 Tooth Speedo Pinion gear | eckertt@epri.co | Restoring your MoPar (Tricks & techniques) | 1 | 02-12-2005 01:02 AM |
Changing 3rd member-need speedo pinion | 440BB | Rear Wheel Drive - Parts Wanted | 1 | 05-12-2002 07:53 PM |
Speedo correction (pinion) info needed. | Dan 97 4x4 | Performance Talk | 2 | 05-09-2000 04:46 AM |