[SUHleen]

Hey guys,

I have a 2011 335is and large pumpkin. I'm going to get the MFactory LSD. It is paid for and ready to be waiting to be built I just do know if I should up the gearing to 2.81. I know I will have quicker acceleration and a lower top speed but my question is has anyone else done the change? I feel like it will not make TOO huge of a difference but while I have it out of the car I might as well make the decision now...

Any input is appreciated!

[musc]

Probably need to do the math on post shift RPM with the new gearing to see where you'd end up. I probably wouldn't do it unless somewhere in the near future you were upgrading to a single or twins that allowed you to shift at 6.5-7k. With stock gearing and stock turbos shifting at 6k, I rarely see below 5-5.2k rpms post shift.

[MFactory]

Feel free to play around with our gear calculator: www.teammfactory.com/gear-calculator

[musc]

Thanks MFactory. The difference wasn't as bad as I thought. I still never see less than 5k post shift starting with 3rd gear logs as it all happens so quick. There is only 6 gears on the Configurator but figuring for 7th the theoretical top speed drops from 185 to 169 if you were to go to 6k in in 7th gear. This is figured for the tires on my 335is.

[MFactory]

We're still stuck with 5spd/6spd in the Honda world

[SUHleen]

I saw the calculator but I was not sure how well it would work since it does not have the 7th gear on there. And I noticed you used 6000 for the redline RPM musc, why is that? Because you shift at 6k? I did not see a huge difference in post shift rpm, but a pretty sizeable difference in the mph for the gears. I already feel like the first few gears go pretty quick. I'm thinking I may just leave it as it is. It is not a dedicated 1/4 mile car so I'm not sure if I want to do that or not, but then again I spend more time on the left side of the speedometer unfortunately lol

Doesn't the M3 use 2.81 or something similar? Is it because of the high revving v8 and a torque curve that is shifted more to the right?

[MFactory]

Changing final drive does not change the shift rpm, as the spacing between your gears still remain the same.

The only thing the final drive changes is the overall speed vs rpm, which is a constant value between all gears.

If you tend to do more traffic light/town driving rather than highway cruising, you will more than likely enjoy a shorter ratio more.

The M3 is a 3.85

[musc]

I chose 6k as that is my shift point on stock turbos. I believe the E92 M3 was like 8k or somewhere in that range so it can get away a shorter gear.

With as much torque as I have now (500+ at wheels), 1st gear is pretty much unusable and 2nd isn't much better. The DCT has a pretty short first gear already. I'd probably leave it as a 2.56. If you are planning on going to a single turbo with a useable redline to 7k or so, then the 2.81 may make more sense imo.

[MFactory]

Yeah, the main thing is whether you will have traction in 1st/2nd

[SUHleen]

I currently do not and plan on running more power. So I think I may stick with 2.56...

Stephen, let me know when a 2.56 is available. I'm going to stick with the stock gearing.

[MFactory]

No worries

[proTUNING Freaks]

Unless you're doing it to a stock or very mildly modified N54 with torque kept low I wouldn't suggest shorter gearing at all. Its a handful to drive and get traction already with a 2.56. Getting an LSD, swapping rear subframe bushings to M3 ones or poly, rear toe arms and a good set of coilovers to keep the car planted is what we'd suggest instead.