gear ratios and torque

Transmission and Drivetrain Tech

  1. Cope

    Cope Fusing with fire

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    I also would not make the swap. If your gonna make a gear change, then make a GEAR CHANGE. I wouldn't even go from 3.23 to 3.73 but im not like most here.
    i dont care about MPG or RPM on the hwy, i enjoy the seat of the pants, neck snapping, pull the front end up from a stoplight kinda ride....

    :steering:

    i will admit that driving around in a car with no AC and cabin temps well over 100 degrees, while doing 45 on the hwy and going def isnt super fun but at a stoplight, where my car is built to run. Its the most fun you can have in a "street legal" ride.

    :thumbsup:
     
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    • cudaFS

      cudaFS Well-Known Member

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      or with the heater on in a 100 degree car, did that with a 64 cuda lol I was trying to imagine the car as something I could do highway, but I love punch you in the mouth, rip your head off, all my previous cars were brutes. truth be said I'm probably going with that again. I'm looking at the silver sport 6 speed, I'll have to call them and check my options, 3:91's with the od, that might work
       
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      • crackedback

        crackedback FABO Gold Member FABO Gold Member

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        Unless this is a 4 speed car, none of the math is going to make a difference.

        There is a component in an auto trans system that is designed to slip... It ALSO multiplies torque WITHIN it's confines... further trashing the math fans. it is not a true 1:1 input/output component.

        More math is sure to follow.

        Ask guys with hottish turbo/auto cars why their cars ET and MPH faster with a 3.23 or 3.55 vs a 4.10 gearset. Think about that for a minute
         
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        • Cope

          Cope Fusing with fire

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          See now were are getting somewhere.

          The hard part is deciding what you want the car to do. You realy gotta be truthful on this or you will never happy.

          Just today i had kinda a bad day at the shop, got home and decided to take the car out to pick up stuff for dinner. Man i love my car! In alll honesty its terrible to drive. Cant see out of the car due to all the cage and the high back race seats but dam it is fun to push it up against the converter at a light and be GONE!

          i get to sit at the light and watch the carbs shake like an epileptic at a light show. Stall it up, the engine goes tight against the hard mount, light turns green, WAAAAAAAA, shift light comes on bump into second and off the gas...

          Ahhhhh. Life is good!
           
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          • cudaFS

            cudaFS Well-Known Member

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            i get to sit at the light and watch the carbs shake like an epileptic at a light show. LMAO that's too funny!!
             
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            • Cudafever

              Cudafever Well-Known Member

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              here is my thoughts. a 2.76 gear would sure kill that big cubic eng torqe aka help to keep it from spinning. But if it spins it will spin for every!
              If you have 4:56 gears, there is a chance of lifting a little and getting it to hook.

              Now that don't really answer your question and neither does asking a question.
              Were is the torque curve going to be on this eng. idle to 5000? (2.76 gear) 5500 to 7500? (4.56 gear) and a big wheel well tubed rear end. (tire height will very this some)
               
            • cudaFS

              cudaFS Well-Known Member

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              the torque would be 1500 to about 5000 give or take, the cars got rusty quarters, It would be awesome to mini tub it, but its a 67 383 fs cuda so im torn between restoring it or doing the resto mod. I know its going to be hard to get it to hook up so I'm exploring every little thing I can to tweak traction so the gear question is mainly hypothetical for now. I'm thinking of doing a 450 thats way more than enough engine, instead of a 496 stroker, but that voice in my head is saying come on man, for the same price you can get a brute. MM's short blocks are the same price either way. I think I might be chasing rabbits, a warmed up 383 with 4:10's that hooks up will still be hard to beat.
               
            • Cudafever

              Cudafever Well-Known Member

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              I understand the restoration side of it.
              But the first thing i would do is add is Sub Frame Connectors.
              that stroker is going to damage the unibody if it ever get good traction.(or constant stress over time) they can be cut off and unbolted, if you ever get the bug for a full restoration.

              You have the 3.23s already, will be a good test for what gearing you may want latter.
              You will have plenty of torque with either stroker to burn the hides off of it.:steering:
               
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              • mopowers

                mopowers Well-Known Member

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                Going from 3.23 to 3.55 isn't worth the cash IMO. It'd hardly be noticeable.

                BTW- I always find it interesting when folks say they are done with a particular thread only to repeatedly reply afterwards.
                 
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                • cudaFS

                  cudaFS Well-Known Member

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                  the connectors are a good idea, all my other bb cars through the years all had the mopar cowl crack passenger side, so I imagine a stroker would really twist up something.
                   
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                  • cudaFS

                    cudaFS Well-Known Member

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                  • cudaFS

                    cudaFS Well-Known Member

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                    I had a turbo laser, it had the typical slight turbo lag, (LOVED that car.) felt like a higher stall tc I wonder if the 3:23- 3:55's with turbo manual acts like a stall...interesting theory
                     
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                    • Bad Sport

                      Bad Sport HALF A BUBBLE OFF Staff Member FABO Gold Member

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                      I can't imagine you would notice much of a difference at the power level you're at.
                       
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                      • famous bob

                        famous bob mopar misfit FABO Gold Member

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                        Changing gears does not affect torque, it will be the same , just applied at a diff. speed or range --------
                        No one ask if he was getting ready to set up a rear , and had both sets of gears. I would definitely go w/ the 355`s if I already had both.
                        I have 3:73`s in my fish, and have wondered what 3:91`s or 4:10 would do to it . Just don't want a one purpose vehicle , like to waste corvettes and mustangs on the hi way if there is a safe distance w/ no traffic.. Pushing 73 , I`m a little more careful now tho. lol
                        That stoplight killer would suck hind tit if u stay in it till my tires quit spinning !
                        -------------------------------(debate thread starter!)-------------lol
                         
                      • CudaFactHackJob

                        CudaFactHackJob FABO Gold Member FABO Gold Member

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                        You're looking at a third of the distance that you have between first and second.
                         
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                        • Cuprum-74

                          Cuprum-74 Moparus Fanaticus FABO Gold Member

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                          I currently have a 3.21 rear, with an A999 (wide ratio, non-lockup mod) and 26.5 inch rear tires, it's just about a dang near perfect all-around driver. I can easily squeal the 245/60 tires and she takes off pretty good. Then again I have a pretty built 360.

                          I did experiment with 3.55's once.
                          The change was not worth it, highway driving suffered a bit for little to no gain.

                          I agree with Rusty, changing rears is not going to magically get you more torque it just moves the torque range quicker or slower (depending which direction you go)

                          With my current setup I can cruise the highway at 70 mph and stay around the 3000 rpm range.
                          I drove to Colorado and back (500+ miles one way) and averaged 16-17 mpg.

                          Now I do plan on rebuilding an A500 that I have and eventually putting a 3.73 or 3.91 rear.
                           
                          Last edited: Jul 19, 2019
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