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3.73 Gears and next Mods

DjDoan52

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I Have a 2016 Mustang GT Premium 6R80 and my father has a 2021 PP1 Mustang GT Premium MT. He supercharged his and the 3.73 gears were spinning to much so he decided to go with a different Gear ratio. My car stock had the 3.55 in an aluminum Pumpkin. We took the 3.73s with cast iron Pumpkin out of his car and put into mine. It immediately had a better throttle response. I don't plan to supercharge mine just maybe a flex fuel tune and some bolt on upgrades.

Curious if anyone believes i made a mistake with the 3.73 gears on a stock GT with the 6R80. It was a direct swap which was surprising going from a Manual to an Automatic?

Also now that its done what's next? What Mods can I do to get the most out of the car?

A Flex Fuel tune is in the future any info on this would be much appreciated.
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robvas

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How did you get an A10 running in your 2016?
 
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DjDoan52

DjDoan52

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How did you get an A10 running in your 2016?
Sorry I was thinking wrong I changed it in the original post yes I have the 6speed automatic 6R80 sorry
 

engineermike

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I’m a big proponent of flex, but the gen2 doesn’t have the logic to adjust timing as a function of learned ethanol. That means you have to rely on knock advance to get the extra timing.
 

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My first stang was same as yours, but with 3.15. I wish it had the 3.55. The 3.73 would also be better than the 3.15.

Generally, the spacing in ratios between the differentials is 5%.

I think you chose well.
 

beefcake

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qwert7699

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I had a 2015 with a 6r80 before my current pp2 and I did a lot of stuff including 3.73 gears. I did 2018 intake manifold injectors and a tune I was planning on pro charging it at some point then I sold it for my pp2 the 3.73 are a really good gear ratio for the 6r80 enjoy!
 

junits15

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Gears have nothing to do with throttle response. I think it’s all in your head especially since you made a minimal change.
its a 5% change, that's going to be noticeable. Wheel torque will be higher which will give it a snappier feel.

3.73 is nice because i think on all coyotes its within the "learnable range" for gear ratios, meaning you don't need to update the tune or BCM to make it work. It just figures itself out.
 
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TonyT930

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its a 5% chance, that's going to be noticeable. Wheel torque will be higher which will give it a snappier feel.

3.73 is nice because i think on all coyotes its within the "learnable range" for gear ratios, meaning you don't need to update the tune or BCM to make it work. It just figures itself out.
I would definately make the change using forscan as well...
 

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junits15

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I would definately make the change using forscan as well...
There's no need, I'm fairly sure all S550's can learn up to 3.73 without intervention. If its not throwing a christmas tree of lights its working.
 

TonyT930

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There's no need, I'm fairly sure all S550's can learn up to 3.73 without intervention. If its not throwing a christmas tree of lights its working.
Won't changing it in forscan correct your speedometer reading?
 

junits15

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Won't changing it in forscan correct your speedometer reading?
I think it can learn up to a point, so it could just work. I haven't personally done it, i've only researched it.

I had plans to go 4.56 that haven't yet materialized.
 

TonyT930

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I think it can learn up to a point, so it could just work. I haven't personally done it, i've only researched it.

I had plans to go 4.56 that haven't yet materialized.
Well I can tell you this for sure, when i changed my wheels and tires from 18 inch to 19 inch and the circumstance of the tires was a little different, the car did not learn the difference. The speedo remained off until I changed it using forscan
 

Grintch

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Gears have nothing to do with throttle response. I think it’s all in your head especially since you made a minimal change.
Pretty sure he is talking about the response to him stepping on the throttle. Which if you think gears don't effect, just start a manual from 2nd instead of first.
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