• Steve Dinan takes shots at BMW piggyback tunes calling them poorly calibrated - Piggyback versus flash tuning

      Steve Dinan is a well respected name in BMW tuning. His products are well engineered, well tested, and backed up with his warranty. They also are overpriced and regularly from a pure performance perspective beaten by offerings from other tuners. There is a 'Dinan' tax so to speak on the parts and he seems to aim for the more casual BMW enthusiast rather than the hardcore market. There is nothing wrong with that and Dinan also has shown they are capable of building motors that power Grand-Am teams to victory in Motorsport so higher level skill is certainly there than what is displayed by the street car offerings. However, he also is given full control of those ECU's through BMW Motorsport.


      Dinan sells flash tunes. It is in his best interest to put piggybacks down and make them appear cheap or inferior. However, he is right that flash tuning allows a greater degree of accuracy and it is more difficult. Full control of a BMW DME through flashing is harder to achieve than using a piggyback to alter the signals the ECU sees.

      There are merits to both approaches including negatives to both approaches. BimmerBoost features vendors that sell products based on both tuning approaches. Steve Dinan does not mention any tuners using both approaches simultaneously omitting a vital area that should be included in his argument. He also does not mention any of the plusses to a piggyback that his flash tunes can not match such as changing boost maps on the fly or meth injection flow safeties. Some tuners are readily combining both approaches to get the best of both worlds so to speak.

      Steve says the ECU is 'lied to' by piggybacks. Saying it is lying rather than modifying the signal is excessively negative terminology that is not really appropriate from a professional. He also states when the boost is raised from 9 psi to 14 psi in his example the car is using fuel for 9 psi instead of 14 psi and timing for 9 psi instead of 14 psi. The ECU then is forced to compensate.

      The factory DME's are capable of adjusting fuel and timing on the fly with the piggybacks. This seems like an odd scare tactic from Dinan considering the amount of miles BimmerBoost members have successfully logged with piggyback tunes. Additionally, even without a piggyback tune the stock DME in modern BMW's is constantly adjusting timing and boost. What does he thinks happens when the cars go into high elevation?

      His points about the transmission slipping and the stability control not working are comments that are really reaching. BimmerBoost has yet to see a piggyback user lose their stability control or have the trans slip for any reason other than too much torque thanks to the tune.

      Steve is right that he has a large computer science department at Dinan. He hires some very talented students from top engineering schools to work for him paying them large salaries. He has some very powerful computers working 24/7 at cracking BMW DME's. However, even he does not have control of all the functions of the factory DME in modern BMW's so slighting piggybacks for not having full control either seems unfair. Why not let the DME do the functions it does best and alter only those that need to be altered? A piggyback does that and his flash tunes also do that. They just go about it in different ways.

      Dinan says they can do things others can not. BimmerBoost has yet to see Dinan do anything on par with other tuners in the street BMW scene. His offerings are consistently outperformed for less money. Yes, he cracked the N63 V8 quickly but since then so have others either thanks to help from someone inside BMW or by getting their hands on the codes in whatever manner they did. What is it Dinan can do that anyone else can't exactly? Where are their projects that blow everyone else away? What performance records do any of their street cars actually hold?

      Watch the video and come to your own conclusion.

      This article was originally published in forum thread: Steve Dinan takes shots at BMW piggyback tunes calling them poorly calibrated - Piggyback versus flash tuning started by Sticky View original post
      Comments 95 Comments
      1. Sticky's Avatar
        Sticky -
        I made a Dinan E60 M5 owner cry in my bone stock DCT M3 from a stop...
      1. blkclk550's Avatar
        blkclk550 -
        Click here to enlarge Originally Posted by alex@ABRhouston Click here to enlarge
        not impressed with their stuff. I was a dinan installer at the dealership and the S3 M3's damn near felt slower lol

        ive installed a few of the S54 superchargers- way less than impressed.


        there was a F10 fully "dinan'ed" out 550 that moved pretty good- but it also was like 30,000 in crap
        was it white?
      1. blkclk550's Avatar
        blkclk550 -
        it was a Dinan VS BMS shoot out F10 550xi i ran 12.1-12.2 Dinan Stage 5 ran 12.4 my price for tune $375 he paid over 20k
      1. Sticky's Avatar
        Sticky -
        Dinan badges are expensive.
      1. alex@ABRhouston's Avatar
        alex@ABRhouston -
        yup.
      1. bobS's Avatar
        bobS -
        A little late dinan.... lol

        They need to really step up their game.
      1. e92mech's Avatar
        e92mech -
        While I agree with the above article in that 1) Dinan is overpriced for comparatively lower performance gain, 2) There are real merits to piggyback tunes and the community experience supports their long-term reliability (and that's coming from someone who uses a flash), and 3) Dinan's comments on transmission slip seem far-fetched...

        From an editorial standpoint, your line that, "Saying it is lying rather than modifying the signal is excessively negative terminology that is not really appropriate from a professional."

        Doesn't that seem a little melodramatic calling into question Dinan's professionalism? Let's be honest. Every single post I've read on this site hates on someone or attacks someone, and it's based on opinion. Dinan has his opinion. I don't agree with him. But still...
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by e92mech Click here to enlarge
        Doesn't that seem a little melodramatic calling into question Dinan's professionalism?
        Not at all I think it's spot on.

        Click here to enlarge Originally Posted by e92mech Click here to enlarge
        Every single post I've read on this site hates on someone or attacks someone, and it's based on opinion. Dinan has his opinion.
        I can't have mine?

        Really, every single post hates on someone or attacks someone? This was just written literally hours ago:

        In addition to the horsepower and torque gains GIAC is able to raise the rev limiter 200 rpm. They are also able to raise the launch control by 200 rpm which is impressive showing good control over the dual clutch transmission software. Additionally, GIAC says they are able to increase the clamping force of the clutches making this a truly complete tune.

        Definitely impressive tuning, check out the dynographs, specs, and video below.


        Criticism is applied where it is justified and praise where it is justified. Sounds like you need to do more reading.
      1. Nugs's Avatar
        Nugs -
        Click here to enlarge Originally Posted by BuraQ Click here to enlarge
        I am shocked to see the article says that no one at bimmerboost has not seen a piggyback resulted in a "transmission slipping", prior to Terry finding a way to "fool" the TCU the DCT had slippage issues with his method of tuning. Currently, Shiv has not been able to find away around it. Maybe Dinan was illaborating on old news and does not know about the progress Terry has made even though I reject his method of tuning. Props go where they should...
        I thought this was the case but I can't remember where I read it. Do you have a link by any chance?
        is this still an issue for DCT cars running a piggyback only?
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Nugs Click here to enlarge
        I thought this was the case but I can't remember where I read it. Do you have a link by any chance?
        is this still an issue for DCT cars running a piggyback only?
        Oh I missed the DCT part I don't know why.

        DCT tuning is something Dinan doesn't have down either or have upgrades for. DCT trans slip can happen with flash tunes as well...
      1. BuraQ's Avatar
        BuraQ -
        Click here to enlarge Originally Posted by Nugs Click here to enlarge
        I thought this was the case but I can't remember where I read it. Do you have a link by any chance?is this still an issue for DCT cars running a piggyback only?
        Just Google it " 335is DCT Slippage " there are boat loads of info on it. Again though, Terry found a way around this but no without limits I assume , however Shiv did not find a work around needless to say he doesn't care as he has moved on to another platform so I heard.

        @Sticky pretty much laid down the benchmark for the limit of a stock DCT. His did not start to slip till 550 wtq and I am not buying Gintani's BS that you need their special softwareEverything needed is in the DME tables via flash only to come near, target, exceed that. The N54 DCT is much more picky about communication with the DME than the N54 AT IMO from what I have seenMark my words a flash only tune will hit 550+ wtq before a piggyback does
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by BuraQ Click here to enlarge
        His did not start to slip till 550 wtq and I am not buying Gintani's BS that you need their special software
        It's a combination of software and hardware if you are going to upgrade the DCT. It isn't BS. ESS claims special DCT software Gintani has been up front about pushing the DCT pumps with their software.
      1. APC Australia's Avatar
        APC Australia -
        Click here to enlarge Originally Posted by BuraQ Click here to enlarge
        Just Google it " 335is DCT Slippage " there are boat loads of info on it. Again though, Terry found a way around this but no without limits I assume , however Shiv did not find a work around needless to say he doesn't care as he has moved on to another platform so I heard.

        @Sticky pretty much laid down the benchmark for the limit of a stock DCT. His did not start to slip till 550 wtq and I am not buying Gintani's BS that you need their special softwareEverything needed is in the DME tables via flash only to come near, target, exceed that. The N54 DCT is much more picky about communication with the DME than the N54 AT IMO from what I have seenMark my words a flash only tune will hit 550+ wtq before a piggyback does
        I'm Fairly sure the COBB software we use for the R35 GTR allows us to adjust DCT pressures and shifts as does the motec stand alone for the same car. Havent had the chance to use the COBB software on a BMW yet though
      1. BuraQ's Avatar
        BuraQ -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        ...DCT trans slip can happen with flash tunes as well...
        @Sticky, it is more common with piggybacks. The only way for a DCT to have slippage is that the driver mod doesnt know WTF he is doing. Does that remind you of anyone ? Click here to enlarge

        Remind you, I have 400+ launches no slippage, but on 3rd driveshaft. I know when and how the clutches do slip.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by BuraQ Click here to enlarge
        @Sticky, it is more common with piggybacks. The only way for a DCT to have slippage is that the driver mod doesnt know WTF he is doing. Does that remind you of anyone ? Click here to enlarge

        Remind you, I have 400+ launches no slippage, but on 3rd driveshaft. I know when and how the clutches do slip.
        Why exactly is it more common on piggybacks?

        I don't know what you mean by the DCT slipping due to driver mod.
      1. Nugs's Avatar
        Nugs -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Why exactly is it more common on piggybacks?

        I don't know what you mean by the DCT slipping due to driver mod.
        I think he means not flooring it in too higher a gear or letting the transmission kick down itself when going WOT. You can get a big slip of the clutches when that happens. Always try to shift manually.
      1. BuraQ's Avatar
        BuraQ -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        It's a combination of software and hardware if you are going to upgrade the DCT. It isn't BS. ESS claims special DCT software Gintani has been up front about pushing the DCT pumps with their software.
        I did not address upgrading the DCT on our cars. I was addressing the actual limit before slippage on our stock DCT.

        Now granted, the M3 and 335is mechatronics are programmed differently. It is obvious since the 335is pushes out more torque than the M3 from the factory it will have more tolerance in handling increased torque without some special DCT software, unless ESS software is "specific" to the M3 DCT controller

        Click here to enlarge Originally Posted by APC Australia Click here to enlarge
        I'm Fairly sure the COBB software we use for the R35 GTR allows us to adjust DCT pressures and shifts as does the motec stand alone for the same car. Havent had the chance to use the COBB software on a BMW yet though
        Not yet.....I had questioned something near to this with them in an email. The question was about being able to adjust the RPM launch parameters as can be done with the GTR, they said it was on their road maps to do but not a priority. So in other words what I gathered from this is if the RPM LC parameters can be changed sure enough the bar pressure on the clutches can be increased.
      1. Sticky's Avatar
        Sticky -
        Click here to enlarge Originally Posted by Nugs Click here to enlarge
        I think he means not flooring it in too higher a gear or letting the transmission kick down itself when going WOT. You can get a big slip of the clutches when that happens. Always try to shift manually.
        I can see that possibility. Never experienced it myself.
      1. Nugs's Avatar
        Nugs -
        That's because M3s have no torque Click here to enlarge
      1. BuraQ's Avatar
        BuraQ -
        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        Why exactly is it more common on piggybacks?
        It would be futile for me to engage into this with you as you will try to defend / justify your client's product.

        Click here to enlarge Originally Posted by Sticky Click here to enlarge
        I don't know what you mean by the DCT slipping due to driver mod.
        Comon man....are you seriously asking me this question ?

        Click here to enlarge Originally Posted by Nugs Click here to enlarge
        I think he means not flooring it in too higher a gear or letting the transmission kick down itself when going WOT. You can get a big slip of the clutches when that happens. Always try to shift manually.
        This... plus not having the car prepped in sport+ mode, or overheating the DCT with improper launches. One big example is brake launching...a big no no for a N54 DCT.