The aforementioned science project was documented on this forum at
this link.
I'm not sure where people get the idea that FGS in any way is hard on the transmission... it isn't. About the only change is there will be more wear on the 1-2 upshift bands/clutches, which previously sat around doing nothing 99% of the time. I'm sure Klink can expound in more detail as I'm not very familiar with 722.x innards.
The valve body part looks a lot less like a science project, and much more like a trial and error project. That's not a criticism, and it was obviously an educated trial and error project, because they wound up with the result they wanted, but it won't be the result most people here want. Simply manipulating the springing around to produce a full-time FGS in a second gear start valve body results in some really odd behavior at low and parking lot speeds. It's a complete buzz kill for me, I've done a couple and then put them right back to stock. A true FGS valve body has differently dimensioned and configured valves and bores on the amplified governor pressure valve (#44 in the diagrams, IIRC, and I may not be RC), and at least one other valve, and these different dimensions, passages, and spring configurations, and even spring placements (they can be on the opposite side of the valves on FGS versus non-FGS versions) enable smooth and predictable transitions and 1-2 / 2-1 shift points at low speeds.
The USA .034 valve body is the cleanest, quickest, easiest way to accomplish full-time FGS in a .036. Note that euro version.034s use a 2.65 diff, and an SGS configuration almost identical to that in the .036.
I personally don't know if I would want a full-time FGS in my.036 unless I also did a 2.24 diff, but that's just me. I will probably do a switchable electronically based FGS one of these days, but even that's not something the blows my skirt way up. Anytime I want an FGS for either traffic or tomfoolery, it's as close as my right foot or my right hand, and in almost all of those situations I am manually shifting anyway, precisely the way the MB Gods intended. That's why that magnificent and strangely unduplicated in the rest of the industry shift gate is there.
I probably won't do this either, but my mind is racing with ways to incorporate the MB shifter and shift gate into my 722.3 equipped 928. Unless Benz has some kind of weird "rights" to that shifter design, why the hell didn't Porsche just use that too? It would've made something already great ever so much the better.
More general chatter:
FGS is not "hard" on anything. Period. Let me repeat that, just in case I was not clear. FGS is not "hard" on anything. Period.
SGS is not "hard" on anything. Period. Let me repeat that, just in case I was not clear. SGS is not "hard" on anything. Period.
The torque "experienced" by the transmission is the same for any given rate of acceleration. Yes, there can be some minor internal stress differences, but those differences are only going to exist in a significant amount at very high loads, and at those loads these transmissions are already FGS, even in stock form, so in other words, they already are designed for it. At normal daily driving acceleration rates, these force differences on various transmission internal bits will never amount to enough to matter.
Some people have discussed why certain models have "B position" switches, and others don't. Note that it is only the 8 and 12 cylinder models that have the "B" switch. This is due to their generally numerically lower axle ratios. It is easy to forget the overwhelmingly important and all defining fact that the fact that these vehicles, and most especially the vehicles that we tend to discuss here, were actually designed by Europeans, for Europeans. The B position switches are to enable heavy engine braking at very low speeds. No, not the kind of engine braking and snappy acceleration from a dead stop that you "Speed Racer" types are thinking of. I probably should have also pointed out that the Europeans I mentioned above were actually "adult Europeans", so no there, Mr. HAM-ilton, they were thinking of starting off and then continuing down one of the incredibly steep hills that they have over there with a full complement of passengers, luggage, and the trailer up to its maximum permitted weight. I suppose they also considered it useful for starting and ascending up that same grade with the same load without requiring something close to full throttle. Note that there is no smooth down shift into first when using the B switch on decel. It wasn't really intended to be shifted into on-the-fly, except at creeping speeds, but no, you aren't going to hurt anything if you do that as well, other than your inner driver's ego, as you jerk and destabilize the vehicle.
The B switches were added to the V8 cars when they decided to use numerically lower axle ratios worldwide as part of a whole package of fuel efficiency enhancements referred to as the "energy concept". These changes were performed around what we would consider the start of model year '82 production. They remained until the advent of the electronically controlled 722.6 transmission, which gave you the ability to pick FGS or SGS on your own, along with two different reverse speeds (!) for that matter. No, the 2 speed reverse wasn't for stunts. It was for backing out of a hill on slippery surfaces. See how that "adult" thing worked at MB?
Do not confuse this with the "S" (Standard), and "W" (Wet) transmission mode switches that many of the European version of these cars were equipped with. "W" was for even lazier transmission response, most suited to slippery weather, and / or putting around in their seriously bad traffic jams. Why didn't we get it? I don't know, but it's just as well. All it would've done with our customers is violently confuse them, and make them complain about "hesitation" even more as they floored their cars at stop lights, wonder what that little thump was, assume it is something bad, and then bring it to us complaining.
On that subject, the more things change, the more that's
exactly how they are now...
)I could find in my area perform the switch. In addition to minimizing the chances of an installation mistake, Jono also knew to upgrade the valve body to address known concerns (for eg. upgraded 2-3 shift kit). In my personal view, it was money well spent. Others (Maui comes to mind) have performed this job themselves, which is a tribute to their skill level and speaks to resources this board makes available to its members. 
Par Excellence! I have to give credit where it is due...
cars !!! 
All this fuss about FGS or SGS makes me wonder about how the hell some of you people drive! I hit triple digits usually several times a day, and I have just never found any of this to be an issue or a factor. Other than Jono and Ron 500E, probably very few of you would hang with me on most roads, yet you're always all wadded up about this first fifty feet of motion from a stop(!?) I just do not understand the fetish over this thing, the drag racers among us obviously excepted...
