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Discussion Starter #1
OK gents (and occasional lady) here's a fresh story:

Sometimes when I don't use my QP for a couple days or more, the transmission seems to forget how to engage the clutch properly. I get a shuddering from a standing start. My solution has been to turn off the MSP and give it a good Italian tune-up, that seems to get it reset and all is well. I have to admit I don't drive hardly at all with the MSP turned off, I'm kind of gun-shy here in the constant crowded traffic and I can't forget losing control of my old Porsche 928 which of course had no traction control. But in my limited experience, my QP will not burn rubber off the line just because I turned off MSP---the mechanical limited slip prevents it, and it still starts engaging at about 1800 rpm no matter what.

Well today, something interesting happened. I was getting a little weird shuddering with the clutch engagement, so I turned off the MSP. From a stop I stabbed the throttle to maybe 50%. Imagine how my eyes widened as I saw my tach go up to 4000 rpm and felt her drop the clutch! WHOMP The rear tires lit up like a drag race! This is happening in the middle of traffic on a crowded avenue, you have to picture it. I was so startled that I took my foot right off the gas ASAP and then got back on more moderately so I got going without so much fanfare and noise.

My obvious question: is this in any way expected behavior? Is this like the secret burn-out procedure for the DuoSelect QP? Or is this a glitch, as I figure it is? I can hardly wait to try it again tomorrow and see if I can get another burnout going.
 

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Discussion Starter #3
This clutch was installed at about 47,000 miles, in 2017. It was further checked at about 51,000 miles in January, at which point there was no measurable wear. It now has about 54,000 miles. Seems unlikely that the clutch itself is mechanically out of adjustment so quickly.
 

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No way this is normal.

1. Your clutch should start engaging long before 1,800 rpm. No exceptions. This is causing way too much slip to not cause overheats on takeoffs. This is why you mentioned in an earlier post about the "smooth" shifting of your car. Sorry, this is not good. Furthermore, there is no way a flywheel spinning at 1,800 rpm can touch a stationary clutch disc each time you drive and not cause excessive wear, regardless of what the "clutch read" suggests. Even during high RPM downshifts, your car will rev-match to within 100 rpms to prevent this.

2. The clutch slippage I described above is the reason why it slipped to 4K at takeoff. You probably ate through about 10% of your clutch life right there. I recommend you get an clutch overheat read - I bet your in for 10 seconds or more by now.

3. Don't trust the clutch reads you've been given. You'll be so happy to see each 1% chipped away at a time, then you'll go in and 50% will be gone. It's just the way it works. I'm not picking on you or being a pessimist - I just see it all the time. The most reliable method is calculating the wear degree based on the written parameters, assuming the parameters have been written properly. This is especially important because based on your clutch behavior, the parameters are definitely off so as a result, your wear degree is likely off as well.

I recommend you spend the $195 at a dealership to get a SD adjustment asap. Even if they can't (or refuse to) change your initial new clutch parameters, they can at least get your wear index back below 5K and get it shifting properly. I'm a little suspect that your car is behaving this way on top of showing so little wear. I'd say the NCCP was not properly written throwing everything off, or at minimum, your PIS is out of wack.
 

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Discussion Starter #5
I think my description was wrong. An earlier post by our friend [email protected]'s said that 1200 rpm is where a QP duoselect should start engaging. Mine does indeed start engaging at 1200 rpm. When I move forward or reverse slowly it is at 1200 rpm. However, it revs higher to complete the engagement, which I thought is normal.

I think I finally get Erik's advice about how to feather the throttle to get it to engage faster. The trick is, you give it gentle throttle to get it engaging at 1200 rpm for about 1 second, then push it harder and you are going, it's engaged and the launch is smooth. I had never done it this way before. I have been just putting my foot into the throttle to whatever point I want to use, and letting the computer do the work. This spends much more time engaging the clutch at a higher rpm.

Anyway here is a video I took today of a basic standing start. I still have not mastered the procedure I just described.

 

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Understood.

My PIS is set at 4.6, which is still wider than spec for the SOFAST3 and it engages at within 50 RPMs of throttle. In other words, if it idles at 900, then you feel the slight "thump" of engagment at 950 RPM tops, maybe sooner. The PIS is only accurate to the reference point set by the new clutch, so the actual number can vary a bit from car to car and still reflect the same performance.

There are 3 advantages to a tight PIS:

1. You'll ultimately extend your time between clutch replacements based on the clutches movement. The closer the flywheel is to the disc (on average) the longer the useful life (the more material of the clutch will be available for use).

2. You'll extend the actual clutch life based on wear. Very generally speaking, the closer the PIS, the less slip, which results in less wear. Engaged driving means nothing - it's slip that wears the clutch. It's just like brakes - you don't wear out your brakes sitting at the light; you wear them out when you're approaching it.

3. More control. I think my method of feathering works, but mainly because I have decent control of clutch engagement. Driving a Sofast car, like an earlier 360 or Cambiocorsa, it's much harder. MUCH harder. The one single upgrade they gave to the Sofast 3 was making engagement more dependent on RPMs, so you can have more control in the low range. I have the luxury of driving a Sofast (gen 1) and Sofast 3 back to back and the difference is apparent. The first gen Sofast system isn't bad either - it's the same setup in the Ferrari Enzo / MC12 platform! It's just the Sofast 3 setup allows you that much more control, assuming your PIS is set up tight.

Finally, I didn't mean to "PIS" on anyone's parade with my last post. I just don't want you to put a ton of credit in clutch reads. They're there as a reference point but it simply won't be directly proportional to mileage, regardless of how consistently you drive.
 

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Discussion Starter #7
OK Erik, I want to add that I appreciate the advice, and the concern for my vehicle. I think another factor here that is maybe overlooked was that as time wore on Maserati and their supplier continued to improve the performance of the DuoSelect system. Remembering your account of the 2007 DS you drove recently.

Pertaining to that, my car has a July 2004 build date, so it has the very first TCU with the early firmware. This firmware is now considered obsolete, to the extent that it cannot be downloaded by shops who subscribe to the SD system. Moreover, the earliest gearbox controllers like mine will only work with this firmware. So this is why I had to replace my dead TCU with a used item which was indeed very pricey due to its being NLA. I believe I had to pay about $200 shy of the price of a brand new TCU. I suppose if necessary I could get a new TCU *and* and new gearbox controller then all would be well for a huge sum.

Why did they keep doing all these updates? Common sense dictates that they were refining the performance, and the operating parameters of the DuoSelect. So I believe it could be assumed that the DuoSelect in my car is actually the worst of all, in some ways.
 

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OK Erik, I want to add that I appreciate the advice, and the concern for my vehicle. I think another factor here that is maybe overlooked was that as time wore on Maserati and their supplier continued to improve the performance of the DuoSelect system. Remembering your account of the 2007 DS you drove recently.

Pertaining to that, my car has a July 2004 build date, so it has the very first TCU with the early firmware. This firmware is now considered obsolete, to the extent that it cannot be downloaded by shops who subscribe to the SD system. Moreover, the earliest gearbox controllers like mine will only work with this firmware. So this is why I had to replace my dead TCU with a used item which was indeed very pricey due to its being NLA. I believe I had to pay about $200 shy of the price of a brand new TCU. I suppose if necessary I could get a new TCU *and* and new gearbox controller then all would be well for a huge sum.

Why did they keep doing all these updates? Common sense dictates that they were refining the performance, and the operating parameters of the DuoSelect. So I believe it could be assumed that the DuoSelect in my car is actually the worst of all, in some ways.
It's more a matter of preference than a better-or-worse scenario. But about the TCUs, be careful to not confuse the variations in part numbers with the software versions for the cars. There are quite a few TCU part numbers for all the years with some requiring a proxi setup via Modis and some just plug and play. I have literally unplugged my TCU and pulled one from another car and it ran fine. No errors and no programming. Both, however were running the CFC 301 software specifically for that model year. The problem comes up when you run the same software configured for a different clutch, which is what happened with the 3+ units of 2006 on. I believe this is what prevents any software updates of old cars - it's not the TCU, it's the fact that there's a different clutch in there and the parameters simply won't work.

As for the software versions, they are the same up through 21925. My assembly number is 19418 (VIN 018323). Check yours - I'm curious now how close together our cars are.

Regardless, as 2005s, mine and your car are running the first Sofast 3 units. Personally, I don't mind it at all. It was initially designed to slip a bit more to simulate the feel of an automatic but with a little manipulation, they can engage just fine, probably even better with a FD DBW. In fact, I think the DBW system is needed the most on the earlier, pre-2007 cars. Again, drive a 2002 Cambiocorsa with the Sofast 1 & 2 setup - it sucks. High rev shifts are great but low end is terrible.

The first update was to the Sofast 3+ beginning in 2006. That utilized a slightly modified bell housing to accommodate a different clutch. I have no idea what affect that made to performance or life expectancy, but the damn clutch is more money, so I'm perfectly fine with mine! $1,050 brand new, can't beat it with a stick.

The second major update was with new software for the Sofast 3+ in 2007, coupled with the different suspension firmware. The new software gave 30% faster shifts (it's noticeable!) and a firm ride with a click of a button. That's what I love about the 2007. On the track, you can't tell them apart, but under normal driving conditions, the 2007 feels more like a sports car.
 

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Discussion Starter #9
Just to satisfy your curiosity my assembly number is 16066, so our cars are about as far apart as two 2005 models could get in the production sequence.

I had also understood that all these QP clutches are twin-plate design, which is theoretically to allow a smoother transfer of the 400 hp through a dry clutch system. My understanding is that as power and torque go up, the more clutch plates you will need, which is why top fuel dragsters have several clutch plates.
 

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Just to satisfy your curiosity my assembly number is 16066, so our cars are about as far apart as two 2005 models could get in the production sequence.

I had also understood that all these QP clutches are twin-plate design, which is theoretically to allow a smoother transfer of the 400 hp through a dry clutch system. My understanding is that as power and torque go up, the more clutch plates you will need, which is why top fuel dragsters have several clutch plates.
Yes that is a fairly early model but all us models in 2005 had the same setup with the same software. The 231 software in the QP was only available in Europe.

All QPs are twin disc. The clutches / part numbers for the 2006MY are different than the 2005 however the overall setup is the same.
 

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OK gents (and occasional lady) here's a fresh story:

Sometimes when I don't use my QP for a couple days or more, the transmission seems to forget how to engage the clutch properly. I get a shuddering from a standing start. My solution has been to turn off the MSP and give it a good Italian tune-up, that seems to get it reset and all is well. I have to admit I don't drive hardly at all with the MSP turned off, I'm kind of gun-shy here in the constant crowded traffic and I can't forget losing control of my old Porsche 928 which of course had no traction control. But in my limited experience, my QP will not burn rubber off the line just because I turned off MSP---the mechanical limited slip prevents it, and it still starts engaging at about 1800 rpm no matter what.

Well today, something interesting happened. I was getting a little weird shuddering with the clutch engagement, so I turned off the MSP. From a stop I stabbed the throttle to maybe 50%. Imagine how my eyes widened as I saw my tach go up to 4000 rpm and felt her drop the clutch! WHOMP The rear tires lit up like a drag race! This is happening in the middle of traffic on a crowded avenue, you have to picture it. I was so startled that I took my foot right off the gas ASAP and then got back on more moderately so I got going without so much fanfare and noise.

My obvious question: is this in any way expected behavior? Is this like the secret burn-out procedure for the DuoSelect QP? Or is this a glitch, as I figure it is? I can hardly wait to try it again tomorrow and see if I can get another burnout going.
Well just Dayummm.
Oh hell Yeah Brother!
 
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