[bm5bullit]

1) The "road" were power gains are measured, either by dyno or acceleration figures?

This road will be all of those M5 owners that do not buy a "base" tune such as the one by Performing Imports. Evolve, Ess, RPI, etc. all make great products that I have used also. But, take note that none of these tuners have responded on this base tune discussion. They will come up with tunes that are of less horsepower, more than likely, and be more conservative/innovative than the base tune. Make no mistake though, performance metrics will eventually put this "base" tune against the others by means of acceleration figures and the dragstrip. No one yet has said that it can't be measured. It's just not a good idea at all to do this on a dyno due to the advanced "adaptability" of the new DME.

2) A unknown/completely new tune to the M5?

I believe that #1 is the "old road" and has been used in the industry for ages (just as old as the other "road" of crazy HP gains and NO proof of it, just advertizing big numbers)

And M'bitious is not going down a "new road" as regards the tune he is getting. Manhart has allready provided the before and after dyno runs AND Vbox data (and Manhart has some slight variations that the other tuners don't have on their M5's (at least not yet)).

It has been stated here over and over that the Manhart, PP and other tunes are using the same "base" tune. Easy to substantiate - just ask them either on the phone or on this forum. Where the other tuners are taking a "new road" is the additional power adders that are not in the base tune. I can't speak for other owners but I personally don't want to punish the factory clutch and driveline for a few more horses unless I am prepared to beef those components up at a later date.

It's obviously gonna be interesting to see what numbers M'bitious gets when he does the same with his car. Then the other (Euro) M5 owners will have even more data to consider before choosing their tune. Hopefully this will get available for other than Euro customers in the future as well

I spoke to Franz at Manhart about their tune a couple of times and my only reservation was the removal of the ECU and shipping this off to them. Anything can happen in transport. If it was done here in the US, no problem.

With all due respect, that must be so much more reassuring than just having to rely on "it feels much more powerful". And easier to come back if the car does not deliver to the claims. Manhart has really put their claims out in the open with dyno and Vbox data. That can obviously be used as a comparison, as they actually provide quantifiable data out there that can be verified on your car after the tune. That some tuners WILL NOT provide the tune to anyone wanting to get their gains verified seems strange (but understandable if dyno operators are not doing things right). Wouldn't it be a possibility to at least get some Vbox (or similar) data on a given speed delta for comparisons sake? (I get what has been said about traction, but others do Vbox runs...).

Answered in #1. I am comfortable with the PI tune and that is the only one I am comfortable with at this time. Although, again covering the performance aspect of the tune, there will be plenty of opportunities by other owners to substantiate the gains. I, for one, will do my 50 to 150 comparo runs against local "hot shots".