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-   -   3:1 gear question (https://www.fordbarn.com/forum/showthread.php?t=53638)

fordman67 11-18-2011 11:47 PM

3:1 gear question
 

Any body have any opinions on making a tudor have enough power to turn a 3:1 gear effectivly .I read that it is not reccomemded but I was thinking a bit of a power increase and it could work...anybody?

Jeff P. / MN 11-19-2011 06:44 AM

Re: 3:1 gear question
 

3-1 works great in my 900 lb. speedster, though I notice the difference with a passenger. Best guess is you should stay close to stock or go to a Ruckstell.

2manycars 11-19-2011 06:58 AM

Re: 3:1 gear question
 

When I lived in Oregon I drove a roadster pickup to northern california for a centenial parade, and it had a 3:1 rear and drove fine, but it was a light car, and the roads were flat. Flat roads are the key here.

fordman67 11-19-2011 11:35 AM

Re: 3:1 gear question
 

I am doing the engine right now and am planning high comp pistons,dual exh. Manifold,high volume intake,stromberg acc carb.My hope is the added beans will make it come together with the 3:1 gears.And it is not terribly hilly here in my opinion.not as flat as some though.

tmodelman 11-19-2011 02:38 PM

Re: 3:1 gear question
 

Has been discussed on MTFCA forum, here is a link

http://www.mtfca.com/discus/messages/179374/230259.html

Seems that with heavier body, like a closed car, the 3:1 gears don't seem to be justified.

Layden B 11-19-2011 04:51 PM

Re: 3:1 gear question
 

You might like the 12 tooth pinion 3.25 ratio. 3 to 1 on many cars does not yield much more speed, just harder pulling at reduced revs. Higher ratios will not hold back as much on downhill, be advised to have accessory outside rear brakes.

Great Lakes Greg 11-19-2011 06:40 PM

Re: 3:1 gear question
 

The stock gearing in my touring seems way too tall until I get three people in the car with me. Weight is the enemy here, and I think a 3 to 1 ratio with 500+ extra pounds in the car would really be a struggle for 20 horsepower.

fordman67 11-19-2011 09:18 PM

Re: 3:1 gear question
 

Thanks for that.I read the thread.I am thinking that if a t makes 20hp.With 6:1 pistons and better breathing otherwise.I would say a conservatively rated 25hp? that is 25% gain.i would think the extra gear would gain a bit of top speed and, or slightly lower engine speed.Either way am I crazy?

rond 11-20-2011 09:08 AM

Re: 3:1 gear question
 

Yes

tmodelman 11-20-2011 11:07 AM

Re: 3:1 gear question
 

1 Attachment(s)
My '27 touring has had both KC Warford with the overdrive that was akin to 3:1 rear gearing, and now a Ruckstell 2 speed rear.

This T has Stipe 280 cam, .060" over alum pistons, oversize intake, NH carb, 'Z" high compression head. Was tested on dyno at MN tour this summer with 18.8 hp at the rear wheels. Stock T's at the testing pulled from 12hp to 15hp at the wheels. The rated T hp of 20 is only that, a rating, and that is at the highest rpm band. You won't be driving your T at the highest rpm band anyway. Don't think you can hit 25hp unless you do a bunch to the engine, like add overhead valve head or Model A intake carb and exhaust with adapter plate to the block.

The KC overdrive was ok for speed, but would not pull easy grade with 4 people on board, so had to shift back to std gearing (3.63 stock gears) to make low grades. Was slow in acceleration when in KC overdrive.

So I replaced that with Ruckstell (stock 3.63 gearing) as I like the underdrive it gives for steep grades. The stock gearing to me is the best.

If you do go 3:1, remember too you have lowered the gearing and stopping power with the T trans brake on the driveline is now reduced too. I have outside Rocky Mtn. brakes on my T for better stopping power anyway.

Jack Innes 11-20-2011 02:39 PM

Re: 3:1 gear question
 

1 Attachment(s)
I tend to agree wit Tmodelman on the axle gear question. My 14 has considerably more power than the average T & it does handle hills & acceleration better but it has the stock gears. The rest of the car runs out of SAFE operating capabilities about when the engine is ready to really perform.

When you think of it, would Ford not have gone to 3:1 gearing if it was at all practical when they were creating the "Improved" car to try to keep up with the growing competition?

fordman67 11-20-2011 05:27 PM

Re: 3:1 gear question
 

Ya know,I. May agree. If u have a rajo and am not sure if u can use the gear.I know not much chance my mild combo will need it.either way once she is together I will revaluate using the stock gears with some fat boys and see how it goes! Hahahaha

John Otis 11-20-2011 06:14 PM

Re: 3:1 gear question
 

Leave it be. There is a reason that "stock" is stock. T's are a great mixture of middle of the road compromises. I think that with a heavier closed car those gears would give you nothing but frustration even if you had a fire breathing monster hopped up T engine under the hood. If you are that determined to have such increased performance get a Model A.

fordman67 11-20-2011 10:28 PM

Re: 3:1 gear question
 

A model A? NEVER! I liked a's just fine until I drove a T...there was no looking back!

This is going to be a fun project....

Dodge 11-22-2011 01:14 AM

Re: 3:1 gear question
 

3:1's are ok in a speedster with some power. They are marginal in a Roadster or Tourning car and horrible in a Sedan. The motor mods you are thinking of work well.
I have a 1915 Centerdoor Sedan with stock rearend gearing high compression pistons
and a shaved head. The cam is bone stock with 1.6 intake valves and 1.5 exh. and mild porting .
I have the aluminum manifold with a nh carb on it and I can run 52mph with no problem and have run it up to 60mph just to see what it would do.
It will even keep up with a stock Model A on the hills.

Sometimes your better off with a few more revs. and some compression.



My 2 cents................

fordman67 11-22-2011 09:58 AM

Re: 3:1 gear question
 

Thank you.I am glad to hear that I am maybe heading in the right direction.I think the gears are just going to be an intelectual debate.I am going to just get the ol gal driveable for now.


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