3.25:1 (approx) gear set

[jeepguy1948]

I am looking for a 3.25-ish gear set for a stock model a diff. Not being a rich man I would prefer to find a good used set but if I can’t I will buy a new set and if that’s the case I need to find out who has them. I can find them for 32-34, will those fit in an A diff.?

[Jim Brierley]

Early '32 are the same as Model A, later '32 and 32-34 will not. I tried a set of 3.27:1 but didn't like them, too hard to get away from a stop light, good on the highway.

[jeepguy1948]

I’m sure that I will get lots of flak but here is my plan; B motor, not original not stock (yes, it looks stock, but it’s not). Burt’s motor, again looks stock but it’s not it’s over $10k ready to install, and it’s made in China. Banger, can be built into a pretty good motor (read your book 3 times Jim) but unless you are a good machinest with the right tools the cost is very high and if you want an OHV set up it’s not only very very high but that’s not stock either. So my choice boils down to either a not stock 4 cylinder (from China!) or an American made more modern motor? I’m going with an aluminum Buick. 3 times the horsepower as the banger but 125-ish Lbs. Lighter. Even with a 5 speed overdrive transmission and 3.27 gears it’s still pretty high.

[Y-Blockhead]

Excuse me for asking but you have a thread going about an O/D. Then 3.25 gears. Then 5 speed. And Model B engine, Burtz engine, Buick engine?

I'm confused, are these all for the same car?

[jeepguy1948]

I apologize Y, I do ramble at times. Bottom line is that I would like to find a gear ratio higher than a 3.25. I know that it is very, very, unlikely but I thought I would ask. Thanks.

[johnneilson]

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You can always opt for a quickchange for seemingly unlimited ratio options.

Available in several different configurations.

John

[BIG KEV]

I'm running a 3.27 gear in my A coupe... 95 HP B motor, pulls the hills great and plenty of power... The stock A crashbox leaves alot to be desired, I was shifting to 3rd at 40 mph. This car will pull away from standard traffic also. When I had the stock 3.7 gear, I didn't use first gear, I just did 2nd to 3rd with stock wheels.

I would not do a gear ratio like that with a 5 speed. Too low of OD and you would need a ton of power to pull it. OHV power in the low 120 range and still you would lug I think.

Quickchange listed above is another idea but will make you very hotrod. Plus the $ out for one is pretty steep.

I am installing a 34 trans behind my banger right now, the clings adapter etc... Gear ratios should make driving even better along with synchro's 2nd and 3rd.

Last thing to touch on is tire height.... If stock wheels and tire size, then a modified A mill will work with 3.2 gears, bump up to later 16,17,18" wheels with 7.00 or 7.50 rubber on them, then its like a gear swap without a gear swap. As stated above I was using 2nd and 3rd gear on the stock A wheels and tires... I went to 7.50-16 and started using first again.

[jeepguy1948]

I would love a QC andI don’t mind the hot rod look but the $$$ is well beyond me. Right this instant I don’t recall the OD of the stock tires on a ‘28 but I’m running 16” wheels with radials and the OD of those is 28”. I remember trying to match the OD of the stock wheel/tire combination so that my gear ratio’s and speedo drive would be unchanged. I’m going to guess that if you are running 750 16 tires you probably are fenderless.

[johnneilson]

If truly you are thinking about the Buick V8 Alum motor.
You may want to think about using a Ford V8 stradle mt rearend. '41 and up
The Model A R&P will work for a while...

John

[nomadpsd]

I'm running a Camaro V8 T5 transmission with a .73 Over Drive and 4:11 rear gears. The equivalent final drive in 5th is 3.00. This is with a mildly built Model B.

[jeepguy1948]

Do you know what RPM you are turning at say, 45 mph Nomad? John, would the overall width be the same or would the newer unit be wider? Thanks to all for the advice!

[johnneilson]

overall width is different, typically wider.
also in the equation is the choice of wheels and tires, those 19" stockers will not take much HP
it can be difficult to find comparison information, try hotrodworks.com
there is a pretty good technical section.
J