Roll racing ST 335is and lsd gearing

gmanz89

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Sep 6, 2018
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09 335xi e92
Hey so I roll race my speedtech single turbo dct 335is with borgs364 and I’m looking I’m looking to get an lsd. What gearing should I go with? Start speed at the roll race is about 60-65mph and is a 1/3 mile run. I’m trying to trap a high mph.
 

NoGuru

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Jan 9, 2018
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What speed to you cross the line at? There are lots of gearing calcs to see what would work. I think one size down from the 2.56 would be 2.81 or 3.08
 

gmanz89

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Sep 6, 2018
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09 335xi e92
What speed to you cross the line at? There are lots of gearing calcs to see what would work. I think one size down from the 2.56 would be 2.81 or 3.08
Around 140-145mph. I can get a deal on the 3.08. Think that’s help?
 

gmanz89

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Sep 6, 2018
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Your gonna lower you mph going higher in gearing , you already have a good mph gear ratio at 2.56
Just started doing more research and my goal is to hit atleast 150mph. Looks like the cheapest way to accomplish that is going to a 27” tire. Now has anyone run a 275/45/18 on the rear of an e92?
 

RuskiRacer

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Jul 17, 2019
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Just started doing more research and my goal is to hit atleast 150mph. Looks like the cheapest way to accomplish that is going to a 27” tire. Now has anyone run a 275/45/18 on the rear of an e92?
I've done that before no issues
 

NoGuru

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Jan 9, 2018
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Just North of Detroit
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BMW 335is
Here is my car setup with 2.56 and what is would do with a 2.81

1622114450988.png

1622114464577.png
 
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iminhell1

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Jun 17, 2018
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Thought when you tried fooling with ratios of the DCT it freaked out because the shift points weren't correct? (MPH v RPM)
 

RuskiRacer

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Jul 17, 2019
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Wierd im almost positive there's an option in xhp to customize rear gear ratios , I had a customer pull it up once and he was like damn I wish I woulda went 3.08 or something so he could get out the hole better for drag racing
 

iminhell1

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Jun 17, 2018
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I think I found the confusion.
The Auto's 6/8 don't have an option to change rear gear (I'm auto and want something else). That must be where they got confused.

And I wonder why the auto's can't change rear gear?
 

RuskiRacer

Lieutenant
Jul 17, 2019
543
211
0
Ride
2009 e93 335i
I think I found the confusion.
The Auto's 6/8 don't have an option to change rear gear (I'm auto and want something else). That must be where they got confused.

And I wonder why the auto's can't change rear gear?
Probably because it doesn't make a big deal to the auto trans if you don't report the gear ratio for the dct it must be more finicky