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      11-16-2017, 03:55 PM   #1
Inflame
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DCT 3.15 differential into 6 speed

I'm curious if anyone has downgraded their 6 Speed 3.85 to a DCT 3.15 differential.

The cost would be nearly zero, just labor, as you can sell the 6mt unit for exactly what you paid for the DCT unit.

Lowering overall RPM per gear per mph is the goal. I understand the car would be a bit 'slower' but a supercharger would help with that

Thank you!
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      11-16-2017, 04:17 PM   #2
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Quote:
Originally Posted by Inflame View Post
I'm curious if anyone has downgraded their 6 Speed 3.85 to a DCT 3.15 differential.

The cost would be nearly zero, just labor, as you can sell the 6mt unit for exactly what you paid for the DCT unit.

Lowering overall RPM per gear per mph is the goal. I understand the car would be a bit 'slower' but a supercharger would help with that

Thank you!
i have a dct and would be willing to swap
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      11-16-2017, 05:47 PM   #3
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If you got an M3 and are trying to save fuel, you got the wrong car lol.

This swap doesn't make a lot of sense I don't see a benefit?
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      11-16-2017, 05:58 PM   #4
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Might make sense on a Harrop car? Otherwise yeah, that's a lot of gear for a teeny engine to pull around, might make a little bit of sense paired with a 285/30-18 rear tire
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      11-17-2017, 09:22 AM   #5
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Might make sense on a Harrop car? Otherwise yeah, that's a lot of gear for a teeny engine to pull around, might make a little bit of sense paired with a 285/30-18 rear tire
If he's going for top speed and fuel economy sure.

Otherwise he's just slowing the car down for no reason.
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      11-17-2017, 12:51 PM   #6
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My reasoning is personal, I own this car for other reasons than it's performance, it is the slowest car in my fleet. My E36 M3 makes more whp out of an NA v8.

Please only comment if you've thought about doing the swap or have done it, i'd like to hear from personal experience from people who have done a ratio swap to a manual car to a lower ratio.
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