3 to 1 gears... how much faster?

Lahti35

Lahti35

Member
So how much speed to do really gain with the 3:1 gear set for the rear axle vs a stock rear axle at say 30mph??

I'm planning on adding brakes, aux ******, high comp head, and better breathing manifolds to my go job and wonder if the 3:1 gears would do all that much... or if I should just spend the $300 on something else...
 
Lets try this again.... all things being constant, ie: driveshaft RPM, how much more speed do the 3:1 gears give?
 
If you do the math, 3:1 is a 21% higher ratio than the standard 3.63:1. So all other things being equal, the same rpm at the driveshaft that produced 30mph with the 3.63:1 will give you 36.3mph with the 3:1
 
If you have a roadster or speedster this is fine, but those gears are not the best for most other body styles, because the weight of the body, plus the passengers can give you a very slow start up.
 
I think it also depends on where you live. I have 3:1 gears with a Ruckstell in my 1910 Touring and I love it. I wouldn't have it any other way. We live in Kansas so we tour on flat land more than anything. It's usually my wife and I with our two kids so not as heavy as 4 adults all the time. Having said that, we also climbed Pikes Peak this summer in the car and it was great. I never used Ruckstell low, low pedal. The lowest was Ruckstell high, low pedal.
Chris Paulsen
McPherson, KS
 
We have a 1915 Touring car with 3:1's in the rear. It has a Ruxstell and I use it like a 4spd. and love it.
It also has a slight touring cam and the high compression pistons from Egge Machine.
This car really runs.
 
As others have already said, unless you have a light car with a very strong engine and keep away from long steep hills you'll probably regret changing the rearend to 3:1.

Perhaps consider a Warford, which in overdrive with a standard 3.63:1 rearend gives you 3:1

 
M2M said:
As others have already said, unless you have a light car with a very strong engine and keep away from long steep hills you'll probably regret changing the rearend to 3:1.

Perhaps consider a Warford, which in overdrive with a standard 3.63:1 rearend gives you 3:1
Click to expand...

I'd love a warford but 2K is a bit much, the $300 gears look more appealing at this point in time. I'm on the lookout for any accessory T ****** that has an overdrive.... so I can go that rout also if I find one. Its a 26 roadster without fenders or top so the car and people load will always be on the light side.

Its pretty flat around here, small bridges that go over the highway are the only hills we have!
 
I have a 3 to 1 Ruckstell in my 27 roadster. When I 1st got the car it was it it and with the stock cyl head it was a constant battle to keep any speed up. I switch to a 3.63 and it was much better. Since then I put a Z high compression head on it and when the 3.63 broke I put the 3 to 1 back in. Wow what a wonderful difference! Much smoother running car. We have lots of hills and it usually pulls them fine. However.....I have purchased a 12 tooth pinion which will make it 3.25 or 3.33 depending on which ring gear (39 or 40 tooth) I decide to run. I think it will be a little better overall, especially when running around with a bunch of other 3.63 geared cars. My next step though is a Rocky Mountain 3 speed aux. ****** I have that mounts just in front of the rear end and replaces the driveshaft too. I also am running AC acc. rear brakes. They work great too. The 3 to 1 will probably end up in my 15 speedster.
 
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