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    • DCT Build Part XII - Build complete, pictures of final assembly, transmission cooler, and Viton seals

      Well, this has been a rather lengthy road to completion but the transmission is basically complete. The car was dropped off by SSP last month to Gintani who should have the motor in by the end of this week. The problem is SSP mounted their trans cooler in the location the heat exchanger for the supercharger needs to go so SSP will need to come to Gintani's facility to re-run their lines as the cooler will need to go in a different location. What took so long for this update? Well, we have been waiting, and waiting, and waiting for SSP to send us details on the Viton seals that required 3 redesigns but never received the information on why these seals are superior to the stock units.

      So, I decided to do my own research and here is what I came up with. These are the stock BMW seals used in the DCT. What is wrong with them exactly? We do not know other than they apparently are not up to the task:










      Here are the Viton seals which delayed the project by 3 months. Viton is a synthetic rubber used for seals, O-rings, things of that sort. Viton was likely used as it is less susceptible to decay and already used in BMW applications such as in VANOS. Viton has much higher temperature and chemical resistance characteristics than the stock seals. Here is what they look like:










      This is the DCT cooler that was mounted by SSP up front. This needs to be moved somewhere else as the supercharger heat exchanger will need to go there. This means SSP will need to come out and run their lines again checking all their fluids and so forth before tuning can take place:














      This is the final assembly. So, the transmission is built but it took about a year longer than estimated. I believe I was as patient as possible and hopefully this will all be wrapped up in December with a built motor, built transmission, a YSI, and a ton of horsepower.





































      This article was originally published in forum thread: M3 DCT Build Journal - World's First BMW DCT Build started by Sticky View original post
      Comments 2372 Comments
      1. BigM62's Avatar
        BigM62 -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Seriously, STFU Iran and tell your pres to blow me.
        LOL. Can I put this on my sig?Click here to enlarge
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by BigM62 Click here to enlarge
        LOL. Can I put this on my sig?Click here to enlarge
        Go right ahead.
      1. c32AMG-DTM's Avatar
        c32AMG-DTM -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        When did I claim to never make a typo? I edited my own post and since you quoted it I edited my quote.
        Sticky - posting "is" when you meant "isn't" is not a typographical error - it's a misstatement.

        Yes, the site notified me that you went into my post and changed the excerpt that I quoted after I'd made my post. Since the way it was initially worded was the whole point of me quoting it and my subsequent tongue-in-cheek "sig worthy!" comment, now my comment doesn't make sense after you altered it.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by c32AMG-DTM Click here to enlarge
        Sticky - posting "is" when you meant "isn't" is not a typographical error - it's a misstatement.

        Yes, the site notified me that you went into my post and changed the excerpt that I quoted after I'd made my post. Since the way it was initially worded was the whole point of me quoting it and my subsequent tongue-in-cheek "sig worthy!" comment, now my comment doesn't make sense after you altered it.
        Now you are telling me when I make a typo and when I don't? No, it was a typo caused by my new iPad. I've been making several as I get used to it. Seriously now?

        Too bad it doesn't make sense, please stop taking the thread OT now or I can just remove you from it.
      1. jjv104's Avatar
        jjv104 -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Regarding increasing the clamping force all they can do at ESS is up line pressure, that's it. I don't know how else you would do it as BMW did the same thing in software updates. We need to make sure we have enough pressure for the stronger clutches.

        You are correct regarding the DCT fluid dissipating heat which is why I am running a different fluid as well as more of it.

        When did BMW start selling the clutch module separately?

        What problem is it you are experiencing with VF?
        I don't know when BMW started selling the clutch module. I just know they sell it now. Realoem.com shows it with a part number and my SA gave me the price.

        My clutch starts slipping on the track at 5k to 6k in the upper gears at less than WOT. Not what I would consider a maximum torque situation. VF has never had this issue before with a SC'd DCT so they are trying to determine if the clutch is slipping or prematurly releasing.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by jjv104 Click here to enlarge
        I don't know when BMW started selling the clutch module. I just know they sell it now. Realoem.com shows it with a part number and my SA gave me the price.

        My clutch starts slipping on the track at 5k to 6k in the upper gears at less than WOT. Not what I would consider a maximum torque situation. VF has never had this issue before with a SC'd DCT so they are trying to determine if the clutch is slipping or prematurly releasing.
        Would you mind posting the real OEM link? I would like to take a look.

        Weird it slips at 5-6k. Let us know what VF figures out.
      1. bobS's Avatar
        bobS -
        Click here to enlarge Originally Posted by jjv104 Click here to enlarge
        Gentlemen,

        Can we please try to keep this post on topic. Sticky started this post with some excellent photos and a plan to do some great upgrades. This obviouly took up a lot of his time. I thank him for sharing it. Obviously the build is not working out as timely as he would like and I understand his frustration. The negative comments are not productive.

        I'm sure many of us DCT owners would like to get more information about the issues with the DCT when supercharging the car. I know I would. I installed a VF-620 SC and have had issues with the clutch slipping at the track. I have spoken with SSP about their clutch packs ($2599). Kris told me that they have sold about 30 sets. Most were shipped to Shanghai for a SC installer there who puts them into all his cars. Kris said that he sold 6-10 in North America but I did not ask Kris for a reference list. So far I've not found one post on the
        forums of anyone successfully using the SSP clutch packs. Drew installed the
        SSP clutch packs but their was another issue with the transmission and he
        ended up having the entire DCT replaced.

        I'm a mechanical engineer and am familiar with wet clutches in industrial equipment. The idea of Kevlar friction material sounds good, but if you research the recomendations from the manufacturer of the material you'll find that
        Kevlar is harder than the paper based material Getrag uses and requires higher
        clamping force, just like a race clutch in a MT requires stronger springs. Kevlar
        also takes up to 5 times longer to break-in vs paper based material. ESS says
        their software upgrade for the DCT ($995) increases the clamping force. If this
        is possible to do with just a tune I think it's prudent to ask what will be the
        next weak link in the DCT. The clutch design, and the DCT too for that matter,
        has many compromises. The paper based material has its advantages. The
        same with the transmission fluid. SSP pushes their own fluid ($50/ liter, the
        DCT takes about 9 liters) as being superior to the BMW fill of Pentosin FFL-4.
        The DCT has a single sump so the fluid must lubricate the gears as well as
        possible, but also disipate heat from the wet clutches and not be too slippery
        so the clutches don't slip. The reqirements for each application is contradictory
        at best. Pentosin is a well respected company and a leader in double clutch
        transmission lubrication for many auto companies. Even BMW dealers sell the
        FFL-4 for much less than SSP.

        Another possibility is a race clutch module that is currently being developed in europe. James Clay from BimmerWorld is researching the clutch to see if it
        might have potential. Preliminary pricing is about $8000 plus install.
        Lastly, if your DCT was abused before the SC was installed, it's entirely possible that the friction material is glazed and requires replacement. BMW does sell the clutch module separately ($1900 - $2400 plus install). In my mind a factory replacement might be the most practical solution. Imagine that.
        I'm also working with VF-Engineering to make sure there is nothing in their software that might be contributing to the problem. The DCT talks to the ECU via the PT-CAN to control engine torque. VF is very aware of the DCT interface and are trying to duplicate the problem I have on one of their test mules.
        Stay tuned.
        Great post. I'm not very familiar with how the getrag shifts or manages the shifts but I can only imagine the software and pressure associated with making those lightning quick shifts would have to be changed/modified if someone wanted stronger clutches and a trans that will hold up under more hp/tq. I imagine the trans has a controlled slip into the next gear which makes it hold power during shifts and that's what makes a dct style modern trans so attractive for performance cars.
        I work for a Allison Transmission distributor and we rebuild/reprogram heavy
        duty bus and truck transmissions all day long. I'm on the sales side but I
        know the electronically controlled trans are very complex, replacing clutches isn't even half of what should be done if it will be done right.
      1. LostMarine's Avatar
        LostMarine -
        Click here to enlarge Originally Posted by jjv104 Click here to enlarge
        Realoem.com shows it with a part number and my SA gave me the price.
        PLEASE SHARE info
      1. jjv104's Avatar
        jjv104 -
        The clutch module is item 5 in the exploded view. The BMW part number is correct. My SA said it lists for $2300. The wholesale price is $1900. Here is the link: http://realoem.com/bmw/showparts.do?...07&hg=28&fg=15
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by jjv104 Click here to enlarge
        The clutch module is item 5 in the exploded view. The BMW part number is correct. My SA said it lists for $2300. The wholesale price is $1900. Here is the link: http://realoem.com/bmw/showparts.do?...07&hg=28&fg=15
        Thank you.
      1. klipseracer's Avatar
        klipseracer -
        I get wholesale rate at my dealer because I've bought so much $#@!. If anyone needs something and is local I'm willing to walk in there with them.
      1. PEI330Ci's Avatar
        PEI330Ci -
        I'm excited for you Sticky....it must be very close to being done!
      1. c32AMG-DTM's Avatar
        c32AMG-DTM -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Why brag about it? Just relax, I expect completion this month or else I have no idea what the hold up is.
        Sticky, are you still waiting? Any indication from your shop on how close they are to returning your car to you?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by c32AMG-DTM Click here to enlarge
        Sticky, are you still waiting? Any indication from your shop on how close they are to returning your car to you?
        Nope, I'm waiting on a call from Gintani. I texted and called and ran into Alex on the road and he said he would call. I'm still waiting on that call.
      1. c32AMG-DTM's Avatar
        c32AMG-DTM -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Nope, I'm waiting on a call from Gintani. I texted and called and ran into Alex on the road and he said he would call. I'm still waiting on that call.
        Sounds good - hope there's news soon. Dynos, subjective feedback, driving impressions, VBOX, whatever you feel appropriate to share. Good luck.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by c32AMG-DTM Click here to enlarge
        Sounds good - hope there's news soon. Dynos, subjective feedback, driving impressions, VBOX, whatever you feel appropriate to share. Good luck.
        I went over today, progress definitely but something I can't mention was not measured right by the shop that provided the part. Basically a critical part was produced slightly out of spec but they are resolving it and it was not just me.
      1. fastgti69's Avatar
        fastgti69 -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        I went over today, progress definitely but something I can't mention was not measured right by the shop that provided the part. Basically a critical part was produced slightly out of spec but they are resolving it and it was not just me.

        I'm going to finish up my math major, do they need someone to help with calculations? lol
      1. e38 prototype's Avatar
        e38 prototype -
        Maybe it's just me.. but how hard is it to make a few -an lines... like seriously?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by e38 prototype Click here to enlarge
        Maybe it's just me.. but how hard is it to make a few -an lines... like seriously?
        It isn't lines. Just wait..
      1. c32AMG-DTM's Avatar
        c32AMG-DTM -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        I went over today, progress definitely but something I can't mention was not measured right by the shop that provided the part. Basically a critical part was produced slightly out of spec....
        To get the replacement part, correctly measured, functioning properly and in-spec... it's already been 10+ days since your visit and it sounded like it was discovered earlier - is this critical part a complex one as well?

        For this to be fixed and up and running... are you looking at weeks? Months?

        I'd bet it's frustrating - hopefully some updates soon.