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2nd Gen diff


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6 replies to this topic

#1 Fbird79

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Posted 2 weeks ago

Hey Im just wondering what kinda gear ratio I can put in my stock 10bolt to get more torque. Im sandblasting and powder coating it so I might aswell throw some good guts in there while its off the car. Thanks in advance

#2 ZumpTA

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Posted 2 weeks ago

If you have the 2.73, 3.23 would be a nice improvement.  3.42 is an option too if I recall correctly.  Personally, I wouldn't go higher even if I could.  3.23 is a good balance between performance and economy.


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#3 b_hill_86

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Posted 2 weeks ago

Depends on your current ratio. There are different carriers and you may need to change depending on what you have and what you want to go with.

Also depends on how you drive your car. I like the ability to drive on the highway so when I swapped mine I went from 2.41 to 3.08. I personally wouldnt ever go any numerically higher than 3.08 for any kind of highway driving unless it was only literally every once in a while.

#4 Fbird79

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Posted A week ago

I wont be doing highway driving, Im thinking more a light to light cruiser, I was thinking of 3.42 or maybe higher, Im looking for torque

#5 JoePeek

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Posted A week ago

I always thought a gear is a compromise situation. Depending on what cam you have, how much torque the engine itself makes, what is your expectation for acceleration, and of course what RPM do you want to cruise at...and at what highway speed. If you say I want to keep my engine RPM below 2300 at 70 mph, and calculate back to see what you get, and say it comes out to a 3.23, and that is a good improvement from what you have now, then OK. Or go at it from the other direction, and say I want to increase my rear wheel torque by 35%, and that maths out to a 3.73, and you don't really get on the highway that often, then that may work best. In the end, for the street, in a car you may find yourself on the highway going 70 MPH, a 3.42, or maybe a 3.55 if you want to stretch it is where I would draw the line. In a 3600 lb. Firebird with a 301 you may want to go 3.73 if you really want a big jump, but be aware that you will wish you had an extra gear if you get on the highway. With a 400 or 455 for sure, a great street gear is 3.08, but the bigger engines make more torque at the flywheel so they don't need the gear a 301 may need....it's a trade off for sure. Gears are like cams, don't go too crazy and you will like it better.



#6 Fbird79

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Posted A week ago

I always thought a gear is a compromise situation. Depending on what cam you have, how much torque the engine itself makes, what is your expectation for acceleration, and of course what RPM do you want to cruise at...and at what highway speed. If you say I want to keep my engine RPM below 2300 at 70 mph, and calculate back to see what you get, and say it comes out to a 3.23, and that is a good improvement from what you have now, then OK. Or go at it from the other direction, and say I want to increase my rear wheel torque by 35%, and that maths out to a 3.73, and you don't really get on the highway that often, then that may work best. In the end, for the street, in a car you may find yourself on the highway going 70 MPH, a 3.42, or maybe a 3.55 if you want to stretch it is where I would draw the line. In a 3600 lb. Firebird with a 301 you may want to go 3.73 if you really want a big jump, but be aware that you will wish you had an extra gear if you get on the highway. With a 400 or 455 for sure, a great street gear is 3.08, but the bigger engines make more torque at the flywheel so they don't need the gear a 301 may need....it's a trade off for sure. Gears are like cams, don't go too crazy and you will like it better.


Thank you, thats exactly what Im looking for

#7 Ponch73

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Posted 3 days ago

I always thought a gear is a compromise situation. Depending on what cam you have, how much torque the engine itself makes, what is your expectation for acceleration, and of course what RPM do you want to cruise at...and at what highway speed. If you say I want to keep my engine RPM below 2300 at 70 mph, and calculate back to see what you get, and say it comes out to a 3.23, and that is a good improvement from what you have now, then OK. Or go at it from the other direction, and say I want to increase my rear wheel torque by 35%, and that maths out to a 3.73, and you don't really get on the highway that often, then that may work best. In the end, for the street, in a car you may find yourself on the highway going 70 MPH, a 3.42, or maybe a 3.55 if you want to stretch it is where I would draw the line. In a 3600 lb. Firebird with a 301 you may want to go 3.73 if you really want a big jump, but be aware that you will wish you had an extra gear if you get on the highway. With a 400 or 455 for sure, a great street gear is 3.08, but the bigger engines make more torque at the flywheel so they don't need the gear a 301 may need....it's a trade off for sure. Gears are like cams, don't go too crazy and you will like it better.

 

 Very good write up Joe  :lol:






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