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Good bye highway gears. Hello 3.55

Airwolf222b

Airwolf222b

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Just swapped the highway gears I had (2.73 i think it said) in my 73 RR to 3.55. I highly recommend. After reading several posts in this forum of guys who had made the swap I gotta say it made a pretty big difference. My little 318 went from a decent little cruiser to a cruiser with a little bit of an attitude. Sure I'm not burning up the roads, but it sure does feel more aggresive. Thanks for all the great info on this site.

51524.jpg
 
2.7 gears suck! They kill the torque. People always think of high gear freeway rpm, but it is much more than that.

Really wakes up a low power engine to change the rear end gears,
 
I like the 3.55/3.54 gear sets. A 3.73 used to be my favorite but now that I have 2 Plymouths with 3.55/3.54, it’s my new favorite
 
No substitute for gearing. My RR (3600) loves my 3;91 but I run 3000 stahl and single plane and gears match my driveline build. High school it was a drag car with 4;56 and pulled after 5 years. Only thing I didn’t pass was gas stations lol
 
If the axle is a 8 1/4", the gear was a 2.71. The 2.73 was never offered in any Mopar. The 8 3/4" axle could be had with 2.76 gears.
Gears do make a difference. I suspect that they may have a bigger impact on cars with shorter stroke engines.
My 383 in Jigsaw felt sluggish with 3.23s but felt alive with 3.91s. The 383 has a 3.38 stroke, if I recall correctly.
 
3.55 is a good street gear. I switched the Dana 60 in my Coronet over to 3.23 gears since I have a Doug Nash five speed with a low first gear. With a normal trans I'd run a 3.55 on the street.

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With the big flat torque curve of my '67 R/T's 440, I am happy with my 3.23's. I did have 3.91's in it for a while, but it was just stupid. I had 3.55's in my 440/4-speed '67 Coronet wagon, and liked them.
 
i have 355s in my road runner good all around gear
 
My Dad had a 73 Road Runner as a executive lease car in 73. I snuck it out to Milan dragway. Brand new car. 318, factory duals, 3.55 gear. It ran 15.90's
Doug
 
I like the 3.23s with a 26" rear tire.
 
The 3.55s in my GTX turns 3000 rpm at 65 mph. Not too bad. It has enough wheel spinning power as is with the 11" PTC torque converter.
 
Not around here in my old cars. Interstate 30/40 interception here in Little Rock area has nothing but grill to bumper truck traffic. One of the highest concentrations of truck traffic in the nation. They are death grounds. I won’t even drive on them in my daily driver.
 
I like the 3.55:1 ratio with the overdrive transmission combination on my street car with the usual 26" to 27" tall tires on these cars.
I think 50 mph in overdrive is about 1,500 RPM?
 
You will like the 3.55 gears,they are the perfect cruiser gears. I just ordered a new Strange Engineering Dana 60 with 3.54 gears for my 71 Charger R/T. Someone robbed the driveline out of the car decades ago. The Dana 60 is s being delivered on Tuesday.

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I agree with Pete. I did the same swap a few years ago. Had an 8 3/4 2:76 and went to a dana 3:54.
What a game changer for cruising and fun.
 
I decided that it would be better for me to buy a brand new Strange Dana 60,instead of paying 3 to 5 grand for an original third generation B body Dana 60,and have to rebuild it before installing it in the car. The Strange Engineering Dana was 3k delivered.
 
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