Back in the dark ages I drove an old 1973 GMC Brigadier dump truck with screaming 671 Detroit with a 5 and 4 two stick transmission. (Yes, It’s a wonder I still have hearing) I was always shifting to keep the engine in the power band.
I was thinking about that and wondered if it would be about the same as using a 3:1 ratio in my Ruckstell rear and installing a Warford transmission in my 1919 T.
Question is, Is the high and low speed gear ratio in the Warford transmission the same as it is in the Ruckstell rear if I install 3:1 gearing?
Or would it give more different speed ratios between the 3:1 Ruckstell and the Warford transmission thus giving me more gear and speed options on the road?
The Warford has ratios and the Ruckstell has ratios. To get the over all ratio you multiply the individual ratios to get an over all ratio in some Warford gear and some Ruckstell gear.
Then you can do some comparing
I think a better ratio for a stock T touring like yours would be a 12 tooth pinion used with a 39 tooth crown (3.25-1) or better yet with a original Ruckstell 40 tooth crown (3.33-1). I have found that the 3-1 ratio is too tall for a stock bodied car, probably OK for a speedster. My experience is that the car is always "laboring" running 3-1 gears and I think it is hard on everything. I prefer to have the car running "freely" on the average road I drive (not needing full throttle to maintain a civilized driving speed.I assume that the elevation is low where you live and not too many big hills.
I hope this helps you.
Yes you would have to buy a 3-1 gear set and set the 13 tooth pinion aside so the up front cost is more. Worth it in my opinion.
Will
I drive a 9513 Fuller (13 speed Road Ranger) with a small cam 855 Cummins so I know all about constantly shifting in hills to try to stay in power band (1700-2100 rpm)
Probably comparing a very narrow range diesel to a model T engine is not a good comparison. The original 2 speed worked for millions and there was even the guy that drove across the US with only high gear. I think more then four gears from a Warford or Ruckstell separately would be a waste of effort in both the installation and shifting.
Jim
What ratio you should be using is quite dependant upon whether you live in flat or hilly country. If flat, you will find the 3:1 ratio very satisfactory at higher speeds. If you are in the mountains or hills, you will spend more time shifting down with that ratio. It is also dependant upon how heavy your car is and how many passengers you usually take. Some heavier cars will not go up hills except in Low/Low which is very slow. Anyway, the choice is yours.
Norm
Remember that the (new) KC Warford is a three speed (low, straight through and high), high is already an overdrive that takes your 3.63:1 ring and pinion very close to a 3:1 gearing. If you change the R&P to 3:1, then your Warford high gear will be 2.5:1, pretty tall for even the lightest Ts, but nice for a 40+hp speedster. That works out to 50mph at 1400rpm.
By leaving the R&P ratio at 3.63:1 with a KC Warford, you'll have a 3:1 final ratio at the flick of the shift lever, and the traditional 3.63:1 in Warford 2nd.
Basically, Warford low is 1.833:1, Warford second is 1:1 , and Warford high is 0.831:1.
Here's a page that shows RPM at given speeds for the just the KC Warford and both 3.63:1 and 3:1 ring and pinions.
http://www.texastparts.com/mm5/manuals/WarfordRPMChart.pdf
Also, Ruckstell low is 1.54:1, Ruckstell high is 1:1.
I spent about a week working out all the available gear ratios and rpm/speed charts for a KC Warford attached to a Ruckstell with R&Ps of 4:1 (40:10), 3.63:1 (40:11), 3.33:1 (40:12), 3.25:1 (39:12) and 3:1 (39:13).
In the end, I just stuck with a Ruckstell and 3.63:1. My second choice would be a KC Warford with a 4:1 R&P with no Ruckstell. Using just the Warford and Ford high, you get about 9% faster on the flats, or 10% more power on hills or a low gear that is 35% higher than Ford low. With both a Warford and a Ruckstell, you get all sorts of low gears that are even lower than stock, how often do you think that Ford low is too high?
If you start spending a lot of time above 45mph on the street, you better think hard about a T's brakes, suspension and your wood spoke wheels.
Just my $.02
Eric