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      12-06-2024, 12:21 PM   #1
Cobra1956
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DCT tune information for gear or LSD swap

As part of my build I am installing an LSD in the 135. I have seen, don't know any of this, that when you change the back of the bus you need to do something to the settings inside the DCT. I had a 3.08 rear diff that is going to be installed shortly. If I understand correctly the system collects information from the abs sensors and that also gets used by the DCT to make adjustments and or shift points. My brain is always slow to remember that this is a result of canbus so it makes sense that this is where the info comes from.

Is there anyone who has a DCT and has changed their diff to LSD or the ratio, and if so, any thoughts are appreciated.

Thanks
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      01-07-2025, 09:22 AM   #2
jasonjoyrides
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I am looking into doing this same swap. I have sourced a cheap 3.08 bolted diff and would like to toss in an MFactory LSD. It seems like the cheapest option (a little over $1k).

As for the difference in ratios, xHP has a "rear axle ratio" option to allow us to change our final drive ratio. I have not been able to find any write ups from someone that did it though, so I can't say for sure that it works. I would expect that it does work though. xHP is almost $500 for the DCT so that does make it a bit of an expensive option.
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      01-12-2025, 11:20 PM   #3
Cobra1956
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I had Randy at Epic tune my DCT. I will be programing it next Friday at the track. They have tuned my s54 stuff and do a lot of work with racers so I know I am in good hands. I will let you know how it goes. I looked into the xhp tune but was not thrilled with the support so I opted to go this route. Must confess to being dumber than a box of rock hen it comes to the computer portion of all this so I am anxious until I get this sorted. There was a nice video from the guy in Australia that did a swap and it looked like the xhp works but I have not had good luck with things not done on this side of the pond.
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