3.27 ratio

bdotson

Member
any one have any experence with the 327 ratio. I seems the 3:54 may not be worth the cost of the change. My truck runs 42 now with the 3:78. I can run it harder but that is the rpm I like to run it. Will the firestones help any with the larger roll out?
 
What is the truck? A standard truck with a good motor and 3.78 gears should run at least 50-55 with ease and stay with the cars. You may have a problem besides the gear ratio. Now, an AA would be different and there are no aftermarket gears available.
 
I have a worn out motor in the Coupe with 3.78 cogs in the rear axle and it will run 55-60 as long as I want it to.

I assume you're talking about an A Pickup? AA's didn't have a 3.78 ratio.
 
Yea its a standard pick up. Runs good and drives good I dont know how fast it will run but it seems to want to run around 42 1900 rpm I have had it faster but I feel you are over working it to run faster based on the sound of the engine. I know many talk of 55 plus miles per hour I just feel this is to much.
 
Is this measured with the speedometer in the car or something like GPS? One of my speedos measured accurately under 30(I cheated and used one of those mobile radar things the local constabulary puts by the side of the road) but over 30-35 it'd register slow.
 
I knew that there was a guy in Colorado making those 3:27 gears years ago, but I had thought he had stopped. I am curious to know if anyone has any experience with them.

I'm running the Volvo overdrive, so no need for the 3:27s, and for my coupe, I have a home built late 40s style quick change that is slated for install.
 
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any one have any experence with the 327 ratio. I seems the 3:54 may not be worth the cost of the change. My truck runs 42 now with the 3:78. I can run it harder but that is the rpm I like to run it. Will the firestones help any with the larger roll out?

Yes, I have fairly new 3:27s in my 1929 Sport Coupe....for touring! It does a great job with stock engine and transmission. Seems to be just right for touring without much strain on the system at all. No problem on street use either. Cheap way to improve upper end..compared to the alternatives;)!
Whereas, I have 3:54 in my roadster. However, it has zephyr gear set in the '39 trans that is even better, in my opinion, for street use, with lots of upper end with lower rpm!
 
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I am running 3:54's in my coupe. High compression head, touring cam and 19" Firestone,s.
It will run 50-55 and above no problem. I do feel that it is still winding up a bit more than I would like. Mitchell would be my next move if I were to make one.
This car is a daily driver

Steve
 
Yea its a standard pick up. Runs good and drives good I dont know how fast it will run but it seems to want to run around 42 1900 rpm I have had it faster but I feel you are over working it to run faster based on the sound of the engine. I know many talk of 55 plus miles per hour I just feel this is to much.

I agree with you and I also like 42 MPH much better than 50 and up. I have installed 3.27 in my friend's 31 widebed PU, but we haven't had it on the road yet. The pinion taper was just a hair off, so we had a machine shop change the taper a bit on the driveshaft. It's easy to check by feeling the fit of the pinion. If it rocks, the taper is off.
 
I agree with you and I also like 42 MPH much better than 50 and up. I have installed 3.27 in my friend's 31 widebed PU, but we haven't had it on the road yet. The pinion taper was just a hair off, so we had a machine shop change the taper a bit on the driveshaft. It's easy to check by feeling the fit of the pinion. If it rocks, the taper is off.
Let us know how it does. I too have a 31 wide bed. I calculate only about 48 mph as opposed to 42 with the 3.78 if my calculations are right
 
Yes, your calculations look right to me. At the same RPM the car with the 3.27 will be travelling 37.8 MPH and the car with 3.78 will be travelling 32.7. Just multiply both numbers by 1.5 to get a good cruising speed comparing the ratios.
 
I ran 3.27's in my speedster for awhile, with standard V8 gears in the trans. It was Ok but not great in my opinion. It was fine on the highway but required some clutch-slipping to get away from a stop, especially if on a hill. I took them out and installed a quick change rear end and use 3.05:1 for highway cruising but switch to lower gears for hill climbing. I find that most A's will cruise nicely at around 2100 RPM. With an A trans it would be easier getting away from a stop.
 
My son, Paul, has 3:27's in his '30 coupe. The engine is warmed up a bit with a "B" Brierley cam and 5.5 Snyder's head. He's been running those gears for about 3 or 4 years and is very happy with the arrangement. We do a lot of highway touring and that gearset is the best alternative to an overdrive - in my opinion. We cruise at about 53mph.
 
Our 1929 Tudor with a stock B motor runs smoother and has a higher top cruising speed using 3.78 gears than our 1930 Standard phaeton does using its built up H & H touring A motor and its 3.54 gears. Darrel Pitts has a stock A roadster with 3.27 gears and it is like an overdrive driving it with its tall gearing. The roadster pulls the hills easily with the 3.27 gears. I wouldn't hesitate putting the 3.27 gears into a roadster. For the extra cost of the 3.54 gears, if I had it to do over again, I would stay with the 3.78 gears, or I would warm the engine up a bit and go with the 3.27 gears.
 
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