I have a 2012 5.0 automatic what gears r better for me
Basically just need it to have a good launch n to keep up w it
U could say a light to light for example n that will b good on the freeway to launch

 

I have an auto. The 3.15 gears are fine because first and second are so steep in the 6r80. Just tune it! a stall converter& 3.15 gears with drag radials will net you 11.30's-11.40's. If anything get a stall converter. I run low 12's with a cai/tune only. It's all up to you really.

 

You have the perfect gears believe it or not. Invest your money in a converter.

 

Funny thing actually. I have a 2013 a6 and my dd is a f-350 4x4 with 3.73s. The f-350 turns less rpm at 70 then my car with stock gearing.
Just thought the results of that would be different.

 

That's because your F-350 tires are much taller than your Mustang tires and your transmission ratios are different. Not really an apples to apples comparison.

 

Yea no kidding.. Traditionally speaking though a truck will turn more rpm at highway speed. I just found it interesting that the truck turned less rpm.

 

you should really consider 3.15 gears... I hear they are pretty nice.

 

They come with 3.15's.

 

Exactly.

 

Lol.....

 

4.10s.buddy had them and picked up. 3 tenths with them. Ran 11.47 with the stock converter

 

In an auto?

 

"with the stock convertor"

 

Listen to these guys, a good Circle D converter from my buddy Chris Sehorn will do more for your car than any rear gear change. It'll cost quite a bit more but it's the way to go fast. Plus you'll keep that super low highway cruise rpm, still be able to knock back good gas mileage.

http://www.circledspecialties.com/c-96-6r80.aspx