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**Mrjeremyt** · 10-14-2013, 09:06 PM

Originally Posted by StangFreak

4:10s

Are you sure?? That's the lower gears available from the factory... Most torque in those gears. Why the change? That's a better question, are you looking for low end or all around?

StangFreak · 10-14-2013, 11:26 PM

Originally Posted by Mrjeremyt

Are you sure?? That's the lower gears available from the factory... Most torque in those gears. Why the change? That's a better question, are you looking for low end or all around?

Basically all around I want a good aggressive gear at the track but that's also good for hwy racing.

**Mrjeremyt** · 10-14-2013, 11:32 PM

Originally Posted by StangFreak

Basically all around I want a good aggressive gear at the track but that's also good for hwy racing.

I would go with 3.55s, just as a good medium. You won't see extremely excessive gains or losses.

StangFreak · 10-15-2013, 12:20 AM

Originally Posted by Mrjeremyt

Are you sure?? That's the lower gears available from the factory... Most torque in those gears. Why the change? That's a better question, are you looking for low end or all around?

I'm not thinking about changing gears just wondering if its the beast option for the A6 with full bultons because if seen some auto with 3:31 running some impressive times mid to lowe 11s. So does that mean if the exact same car with 4:10s would run better?

**kdanner** · 10-15-2013, 01:41 AM

Originally Posted by StangFreak

I'm not thinking about changing gears just wondering if its the beast option for the A6 with full bultons because if seen some auto with 3:31 running some impressive times mid to lowe 11s. So does that mean if the exact same car with 4:10s would run better?

The problem with a gear like 4.10 and this trans is traction. I did run a 4.30 for a long time and on the rare occasion it would hook it was badass the way it picked up the front end. The 3.31 just made it a better car, it was just as fast, and it goes down the track every time now. Think of it this way, let's go old school C-4 trans, those had a 2.46 1st gear. The 6R80 has a 4.17. So, 4.17*4.10=17.097 ratio in 1st gear. Now try to get a C-4 the same. 17.097/2.46=6.95. You'd agree a C-4 and a 6.95 is a hell of a lot of rear gear right? That's the same you're getting with a 4.10 and a 6R80. Even the stock 3.15 gear is like a 5.34 axle with a C-4. If you wondered why these automatics run so good, right there is a big reason why. Leave the stockers in it, or maybe change to 3.31 to get the very slightest bit more out of it.

StangFreak · 10-15-2013, 09:14 PM

Originally Posted by kdanner

The problem with a gear like 4.10 and this trans is traction. I did run a 4.30 for a long time and on the rare occasion it would hook it was badass the way it picked up the front end. The 3.31 just made it a better car, it was just as fast, and it goes down the track every time now. Think of it this way, let's go old school C-4 trans, those had a 2.46 1st gear. The 6R80 has a 4.17. So, 4.17*4.10=17.097 ratio in 1st gear. Now try to get a C-4 the same. 17.097/2.46=6.95. You'd agree a C-4 and a 6.95 is a hell of a lot of rear gear right? That's the same you're getting with a 4.10 and a 6R80. Even the stock 3.15 gear is like a 5.34 axle with a C-4. If you wondered why these automatics run so good, right there is a big reason why. Leave the stockers in it, or maybe change to 3.31 to get the very slightest bit more out of it.

What do you think about the 3:55 and you think they trap me in 3rd if raised the rpms to 7700 with the BIM?

**kdanner** · 10-15-2013, 10:33 PM

Originally Posted by StangFreak

What do you think about the 3:55 and you think they trap me in 3rd if raised the rpms to 7700 with the BIM?

I'd say you won't make it in 3rd unless the car runs a really low trap speed, or unless you put a really tall tire on. 3.31 with a 28" is the best bet for most cars to be able to trap in 3rd. Once you get to like 126-127 MPH, time to start thinking about 3.15 with a 28" or 3.31 with a 30" tire.

**Yagermeister** · 10-15-2013, 11:19 PM

Originally Posted by StangFreak

I'm not thinking about changing gears just wondering if its the beast option for the A6 with full bultons because if seen some auto with 3:31 running some impressive times mid to lowe 11s. So does that mean if the exact same car with 4:10s would run better?

StangFreak, you're probably thinking of my red auto. Had a Boss intake and 4.10s and always crossed the finish line in the middle of 4th...not ideal. Went to 3.31s and cross the finish line at the top of third saving time to make that last shift, easier to launch, have great gas mileage again (just in time for e85!)

StangFreak · 10-16-2013, 12:44 AM

Originally Posted by Yagermeister

StangFreak, you're probably thinking of my red auto. Had a Boss intake and 4.10s and always crossed the finish line in the middle of 4th...not ideal. Went to 3.31s and cross the finish line at the top of third saving time to make that last shift, easier to launch, have great gas mileage again (just in time for e85!)

Oh yeah i haven't gotten the car to hook off the line and the extra mpg wont hurt, this is with the RPMs set @ 7700? If I happen to run into used 3:31s would I have any issues with them oppose to ordering new one from AM ? And can they be set to have a" kick" as I like to say, I like how the 4:10s feel.

Thanks

**Yagermeister** · 10-16-2013, 03:11 PM

Originally Posted by StangFreak

Oh yeah i haven't gotten the car to hook off the line and the extra mpg wont hurt, this is with the RPMs set @ 7700? If I happen to run into used 3:31s would I have any issues with them oppose to ordering new one from AM ? And can they be set to have a" kick" as I like to say, I like how the 4:10s feel.

Thanks

Used gears can sometimes be risky due to the wear on them. I'd go new Ford Racing ones purchased from anywhere reputable. As mentioned before the "kick" is in the tune. The 4.10s do have a kick due to the torque multiplication but it'll depend on the goals you have but 3.31s work better for me with what I am trying to do