rear end suggestions

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dirtywaterdiver

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So, I did the AOD swap in my 59 Edsel with 15" wheels and a 292 and stock rear end with 3.10:1 now.

The trans was for an 88 thunderbird with a 302.

What rear gear ratio would be a better set up for this vehicle now?

Interested in your thoughts.
 
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I put an 8 inch rear end with 3.50 gears from a Maverick in my '54 Ranch Wagon with a 302/AOD combo. Not running yet but the guy who did the gear swap felt the 3.50's would be a good combo.
 
I’ve done a number of O/D automatics in place of 3sp autos. I’d drive it first and see how it works for you. On the hills around Seattle, 3.5’s work out depending on the engine vehicle combination. But when I’ve had to do a change I’ve gone to 3.7’s or 4.11’s. Depends on what I could find available. Most of the stick shift o/d’s used those range of gears.

It’s hard to compare an auto to a stick, the torque converter makes the auto more forgiving of the gear ratio in my opinion. Just my opinion. If it’s a lock up converter that’s another variable. So I’d drive it for a bit, keep an eye on the tach and speeds and where it feels “nice” or “right” and go from there. If it’s a 9” in the Edsel, there’s a very wide choice available. But you don’t want to spend the time or money to do it twice.
 
I have a 5.0 with factory FI and an AOD that came directly out of a '93 Mustang in my '54 Customline. The stock Mustang rear gear was 3.27. My stock '54 rear gear is 3.31. Almost exactly the same. In addition, there's about a 50lb weight difference between the Mustang and my '54.
The weight of your Edsel is probably 700-800 lbs more than my '54. I would surmise a 3.50 gear would do well in your situation.
 
We had a 302/C-4 with 2:75 rear in our '41 ford. I no problems cruising on highways. Our 302 had close to same H.P.( somewhere around 200) as your 292 I would imagine. also couldn't beat the mileage!
 
Still haven't figured out what the love affair is with higher rear end ratio's. Let me just say this....in '58, Ford offered a 2.91:1 rear end ratio with 292. I saw one in a junkyard, pulled it and put it in my '57 with 292. What a blessing it was on the highway, increased my fuel economy vastly over what was originally in the car. If I remember right, it originally had a 3.67:1 ratio or somewhere in that neighborhood. After making the swap, I saved $$$ on gas, not to mention, the 292 didn't even blink.
 
Almost every 80's on up Crown Victoria's Grand Marquis Town car came with the AOD and 2.73 gears. 3.08 was a towing option gear. Of the 2 Town cars we had one that had the 3.08, both drove the same. Nice relaxed cruising.
 
One more thing to consider, put in a vacuum gauge up where you can watch it while driving. Depending on if you live in hilly country, and the fact the a 292 is a torque monster, your gears may be just right.
 
2.73 was the standard axle ratio for AOD-equipped 5.0 Fox Mustangs; 3.27 was optional. My 1988 Mustang 5.0 LX convertible was equipped with an AOD and 2.73 axle ratio. I could barely break loose the 225/60R15 tires from a dead stop, but I managed 25.2 mpg south of the Grapevine on I5 (flat/w light traffic). How do you want your car to perform? Unless you plan to do some off-road racing, you should be happy with 3.10 gears. However, with 2.73 gears, I would leave it in "D", not OD, until I reached 40-45 mpg to prevent frequent shifting in and out of OD and lugging engine. That probably wouldn't be necessary with 3.10 gears.
 
dirtywaterdiver said:
So, I did the AOD swap in my 59 Edsel with 15" wheels and a 292 and stock rear end with 3.10:1 now.

The trans was for an 88 thunderbird with a 302.

What rear gear ratio would be a better set up for this vehicle now?

Interested in your thoughts.
Click to expand...

Don't know if you are looking for fuel economy or low rpm cruise, but your
3.10:1 ratio with the AOD in over drive will be 2.33:1, and in high will be
back to 3.10:1.
Hope this helps.
 
Daves55Sedan said:
Still haven't figured out what the love affair is with higher rear end ratio's. Let me just say this....in '58, Ford offered a 2.91:1 rear end ratio with 292. I saw one in a junkyard, pulled it and put it in my '57 with 292. What a blessing it was on the highway, increased my fuel economy vastly over what was originally in the car. If I remember right, it originally had a 3.67:1 ratio or somewhere in that neighborhood. After making the swap, I saved $$$ on gas, not to mention, the 292 didn't even blink.
Click to expand...

My 57 Skliner has the taller factory optional gear. Think it's like a 3.50:1. When it had the 2 barrel on it at 70 MPH it got 12MPG. It's a heavy car, and is chugging about 3,000 RPM at 70. It wasn't too bad at 55MPH, but seemed like it really ate fuel over 55.

Since mileage was crappy to start with the tri=power I added was an easy choice.
 

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Some info I should have included. It has an Edelbrock 4 barrel and a Mummert intake on it.

The car is a cruiser. Lowered 3", continental kit, etc. Just looking for the most efficient set up which is why I was curious.

I know they had 3 sizes for V8, one I6 and a 2-speed or a 3-speed transmission available in 59s. 6 variations of gearing I was just wondering if there was a "better" match for what I have now.

The 292 sure seems to like to run at easier rpms by the sound of it.
 
dirty, if you have either the stock cam or an aftermarket with less than 220 degrees duration @ .050 lift, you should be good to go as is. I don't think your mpg will improve with a ratio swap. If you are more interested in improving acceleration, look for something in the 3.50-3.70 range. Keep in mind that overdrive doesn't help town driving.

By the way, has the Mummert intake hurt Low-end?
 
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Most 3 speed o/d’s came with something like a 3.9x rear ratio. Maybe 4:11’s in a heavier car, maybe a 4:27 like the 55/56 6 cyl wagons. Might get a 3.7x living in Kansas. Those ratios still work pretty well with a 2.5 or so 1st, 1.5 or so 2nd, 3rd direct, and a .7 o/d.

Same as I said above. But give it a shot. You’ll know after a few miles, and a lot depends on how you drive and the geography. It’ll let you save your money or spend it wisely.
 
Gene F said:
My 57 Skliner has the taller factory optional gear. Think it's like a 3.50:1. When it had the 2 barrel on it at 70 MPH it got 12MPG. It's a heavy car, and is chugging about 3,000 RPM at 70. It wasn't too bad at 55MPH, but seemed like it really ate fuel over 55.

Since mileage was crappy to start with the tri=power I added was an easy choice.
Click to expand...
With our '41 ford Fordor (3200# +or-), 302 2 brl/C-4/2:75 gears/235/75 tires in back with trunk & back seat loaded to the gills, we got almost 24MPG on a Florida trip. Of course it's down hill from NY to FLA!!!
 
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