I'm in the middle of restoring my '27 coupe rear end...getting ready to order parts and I've had some great advice on this forum already. Since I'm just starting, I'm keen to all the "good" advice I can get!
I've come across the 10 tooth pinion gear.....somebody comment on the advantages or disadvantages to using it over the standard 11, and do you need a different ring gear to go with it? I'm not going to go with the 3 to 1 set up..since several places it is recommended only for the more powerful engines or very light vehicles.
My ultimate goal is a nice "driver" with some practical improvements, such as the free - floating rear hubs, improved head, and perhaps an "A-rod", and solid state electronics. (These are all still speculation. Thanks in advance!
If you live in hilly country, a 10 tooth is a good option in lieu of a Ruckstell. A '27 coupe is heavy and with a stock engine the power to weight ratio is pretty marginal. Use the 10 tooth with the standard ring gear. Disadvantages are a somewhat slower top speed (not a disadvantage in some views) and a very slightly increased risk of breakage due to the 10 tooth design.
I have a 26 coupe,it is extremely hilly here,i put in a ten tooth pinion and really couldn't tell any difference,installing a "Z" head will make all the difference in power for hills.It does use the standard 40 tooth ring gear for a 4 to1 ratio as opposed to 3.63 to 1.
I run a Ford 10-40 gearset with modren overdrive in the ol' brass picup. The Fronty doesn't lug real good, so the 10/40 is good for takeoffs.
Before Ford came out with its 10 tooth pinion, there were others that required a different ring gear, so be sure yours has FORD on it.
You can copy these pages from the "Best of Murray Fahnestock" to your computer and blow them up for legibility:
Thanks all....that's a great article, Rick!
l had a 10 tooth in my 13 runabout, quick , really quick off the mark, but screamed at 46 mph, trying to keep up with the others, unforunately that was the most like cause of my engine failure some time later (flogged out centre main top half ), But in the hills wow.......
I put a 10 tooth pinion on my 1914 Town Car, the thing is full of oak and weighs a ton...
All my others 24 coupe, 17 Touring 15 speedster and 14 touring use the 11 pin. The single biggest improvement is the Al head with a 6:1 compression ratio. I have that on the 15 and 14 touring and they make a huge difference. I milled 100 thou off the head on the 24 coupe and it made very little difference. I tried to compute the compression ration and 100 thou only seems to raise it by half a ratio. Maybe I made an error.
To get the best overall performance I would recommend the 6:1 Al head and an 11 tooth pinion.
Tony, A Stipe 250 cam would also help move that Town car up the hills.
A couple years back, I restored a 13 PU to climb Mount Evans (over 14,000 feet). I installed a 10 tooth pinion. Turned out to be overkill as I pulled the mountain in high. I also had a Ruckstell but never used it. I am now running standard gears, but will change to 3-1 this winter.
Unless your T is really light, such as a Speedster, or the 13 Runabout, a standard gear is really hard to beat.