RE: Speedometer gear options - caution - long reply

[Steven Charette <stevec@xxxxxxxxxxxxxxxxxxxx>]

Tim and Rich,
	We were making them but have exhausted the supply of internal
components for the original 3-hole cases.  The last few we built we had to
hand make some of the little internal parts and they just got prohibitive in
terms of cost.  We've also tried some 4-hole cases that are available, but
ratio availability is limited.  Sadly with the advent of electronic
speedometers, cables and their associated accoutrements are rapidly fading
into obscurity

	Once we've finished moving we may look into buildling the entire
adapters but again, they won't be cheap.  We will also have room to run the
machines to make the pinion gears.  The prototype gears look good but we
still have to test run a gear in the '64 for durability.

	As an aside, a few of you who have been here know we've run this
place out of one half of a 1300 sq foot pole building since 1992.  Picture
6-8 retirees square dancing and you have an idea of what working here is
like.  Spin your partner to the drill press and dosie-do to the welder - bow
to the cable bench and back again.  It's going to take a little while to get
everything up and running, but we'll have room to do a lot more much more
efficiently than in the past.

	Back to speedos, the best (most cost effective) way may well be a
ratio adapter mounted under the hood or the dash.  It will take a pair of
cables, (or some kind of adapter coupling) but with a full set of pinions
(16-21 tooth) and a limited set of adapter ratios we should be able to
handle most combinations.

	As a reminder, here is how to calculate the pinion required.  

1.  Multiply the axle ratio by the number of teeth on the transmission
output shaft (in our case 8 teeth)

		In Tim's case 4.56 x 8 = 36.48

2.  Multiply the tire diameter by pi (3.14159).  This gives the tire
circumference.

		Not sure what Tim's using, but for the sake of this example
we'll use a 28" tall tire.
		28 x 3.14159 = 87.96452

3.  Divide 63360 by the tire circumference calculated in step 2.

		63360 divided by 87.96452 = 720.283

4.  Divide the result of step 3 by 1000 (slide the decimal 3 places to the
left).

		720.283 divided by 1000 = .720283

5.  Multiply the product of step 4 by the product of step 1 and you have the
correction factor.

		.720283 x 36.48 = 26.2759

6.  The result of this calculation means Tim needs a 26 tooth pinion.  Since
it is not possible to put more than 21 teeth on a pinion for the '62-'65
transmission, Tim will need a ratio adapter.  Take the number of teeth
calculated and divide it by the number of teeth on the pinion you have, and
you have a correction factor.  Let's assume Tim has a run-of-the-mill 16
tooth pinion:

		26.2759 divided by 16 = 1.64224

7.  Divide 1 by the correction factor and you have the percentage that the
output must be corrected, or the adapter ratio:

		1 divided by 1.64224 = .6089

	Tim (based on a 28" tall rear tire) needs a .609 ratio adapter.
Most ratio adapters have 4 gears inside which mathematically limits the
number of ratios available.  Tim would want to round up to the nearest
available ratio, so any error will result in the speedometer reading faster
than actual vehicle speed.  The closest ratio we would theoretically be able
to build would be .6191 - if the correct sequence of the 4 internal gears is
available.

	This gear availability, as well as case and internal shaft, spacer,
and washer availability are the reason we've temporarily discontinued the
ratio adapters.

	For those who A) use a spreadsheet, and, b) abhor long math as much
as I do, paste the following formula into a worksheet cell, put the axle
ratio in cell B6, and the tire diameter in cell B4.  


=SUM(8*B6*(63360/(3.14159*B4))/1000)

	Until we can get back in full production, please feel free to
contact us at tech@xxxxxxxxxxxxxxxxxxxx with 1) tire diameter, 2) rear axle
ratio, and 3) speedo pinion you have and we will research part availability.

Thanks,
SC



-----Original Message-----
From: Rich Kinsley [mailto:rlkinsley@xxxxxxxxx] 
Sent: Sunday, December 13, 2009 8:31 PM
To: 1962to1965mopars@xxxxxxxxxx
Subject: RE: Speedometer gear options


Doesn't Imperial Services sell one? I'm thinking it was around the $150ish
range? I know I have some info on it somewhere, but where?

Rich Kinsley '64 Dodge Polara 4dr 318poly w/goodies
====================================================================
Ollie wrote:
> 
> These people fixed me up for my Satellite 
> http://www.speedometersolutions.com/
> Ollie
> ----- Original Message -----
> From: "tim helma" <daytona92@xxxxxxxxxxx>
> To: <1962to1965mopars@xxxxxxxxxx>
> Sent: Sunday, December 13, 2009 5:01 PM
> Subject: Speedometer gear options
> 
> 
> 
> 
> 
> In my 65 Belvedere, I am running 4.56 gears in the rear end and with 
> the
> 
> later 727 trans I was running, getting the proper speedo pinion was 
> not a problem. Now that I am switching to a 65 cable shifted 727, what 
> are my options for getting the speedometer to read correctly? I'm 
> guessing one of the old Stewart -Warner ratio adapters that the Race 
> Hemis came with would be pretty difficult to find, but that would be 
> the cats meow if I could get one. Anyone have a solution for me?
> 
> Thanks
> 
> Tim Helma
> 
> [Non-text portions of this message have been removed]
> 
> 
> ----
> Please address private mail -- mail of interest to only one person -- 
> directly to that person.  I.e., send parts/car transactions and 
> negotiations as well as other personal messages only to the intended 
> recipient, not to the Clubhouse public address. This practice will 
> protect your privacy, reduce the total volume of mail and fine tune 
> the content signal to Mopar topic.  Thanks!
> 
> '62 to '65 Mopar Clubhouse Discussion Guidelines:
> http://www.1962to1965mopar.ornocar.org/mletiq.html.
> 
> 



Rich Kinsley '64 Dodge Polara 4dr 318poly w/goodies


----
Please address private mail -- mail of interest to only one person --
directly to that person.  I.e., send parts/car transactions and negotiations
as well as other personal messages only to the intended recipient, not to
the Clubhouse public address. This practice will protect your privacy,
reduce the total volume of mail and fine tune the content signal to Mopar
topic.  Thanks!

'62 to '65 Mopar Clubhouse Discussion Guidelines:
http://www.1962to1965mopar.ornocar.org/mletiq.html. 


----
Please address private mail -- mail of interest to only one person -- directly to that person.  I.e., send parts/car transactions and negotiations as well as other personal messages only to the intended recipient, not to the Clubhouse public address. This practice will protect your privacy, reduce the total volume of mail and fine tune the content signal to Mopar topic.  Thanks!

'62 to '65 Mopar Clubhouse Discussion Guidelines:
http://www.1962to1965mopar.ornocar.org/mletiq.html.