Rear end gear selection

[Thedeputy]

Now that I know the power and torque numbers from my 440, see topic 440 power reality check, I would like to improve the driveability some more. Overhere the speedlimit on the freeway is 75 mph (120 km/h). I have no plans to race the car, just enjoy cruising it around town on a nice day.
The 3.91 gears that are currently out back are too short for me so I would like to go a little longer.
I have 3,55 gears for the same casing and also 3,23 for a 489 casing (for which I have no housing).

I would really like to use the 3,23 gears but I'm afraid with the tall 28" tires and long gear the car will feel too slow. Max torque is at 2500 -3500 rpm.
Btw, I also have a wide gear ratio A833 with 3,09 first lying around that would help in getting rolling from a standstill.
Please share your advise based on the power and torque numbers in my 440 power reality check topic.

Thanks and best regards,

Antoon

 

[69Runner]

You will have no problem with the 3.23's. My 67 Coronet has a 2.94 open rear, 2.66 first gear and modest 1976 steel crank 440. I'm even thinking of using a 2.76 / 489, just for fun cruising. Oh, and the back wheels are 26.5".

 

[lewtot184]

i use 3.23's with 28" tall tires and sometimes i wish i had 2.94's. big torque engines don't like nor do they need lower (higher numerically) rear gears.

 

[66Satellite47]

I think with a 28" tire you would be happy with the 3.55.

 

[SublimeSixpack]

You mentioned around town cruising, with that said you'd probably enjoy the 3.55 gears. But if much of your driving will be cruising on the highway I'd go with the 3.23's. The 3.23's would even be fine around town with the torque of a 440. That's what I run in my '69 Super Bee with 440 SixPack engine.

 

[Thedeputy]

That's what I was thinking as well. Will the wide ratio A833 gears, 23 spline input 26 spline output, fit on the 30 spline output shaft of the 69 b-body trans that is installed right now?

 

[Ranger16]

I am not knowledgeable enough to get into this based on numbers, but I can tell you that I am running a 3.23 behind a factory A833 and a 383 and I have no problems or complaints (plenty of torque). At 70 MPH she sits at about 2800 RPM (245/60/15 rear tires) and gets 16.6 MPG.

Based on your type of driving, I think you'd be very happy with the 3.23.

 

[66Satellite47]

My '70 Barracuda 383 had 3.23 gears & 12" converter. A smaller converter & 3.55 gears would really have been much better. Although I would routinely take the speedo well past the 120 MPH mark. DP4B, 3310 Holley, cheap 1 3/4" headers. Beat countless 351 Mach 1 Mustangs, several 454 Chevelles. Can't imagine what my '65 Coronet could have done on the street.