If you look into it, theres more than just parallel and sequential, different engine builders use lots of different 2 turbo set ups.
What theyre called is all just semantics, lets call em "2 turbo systems".
Since the 1.9JTD 16v twin turbo (or whatever you want to call it) was planned for Alfa Romeo but never happened, I would be similarly surprised if the set-up is ever applied to the 2.0 JTD.
In any case, the Fiat Group need to concentrate on applying MA to the JTDs. This would make them much more competitive at least in terms of power and CO2 outputs compared to say, BMW. At the moment, there is no comparison, the Germans hold all the trumps.
MA is currently being worked on for JTDs. The 2.0 JTD twin turbo is already used in the 9-5, the Insignia will get it soon and Fiat cant afford to be left behind when every one else is going the multi-turbo route. As the 2 turbo version exists already it would be madness NOT to MA it and only MA the single turbo. And anyway MA AND 2 turbos would be even better than MA or 2 turbos alone.
The Germans are going great, but Mitsubushi is overlooked-their 1.8 TD has 2000bar common rail, is all alloy and has variable valve timing, it makes 150PS/221LBS/FT, not bad for a 1.8. Dont think BM's diesels, however good they are (and they are) use VANOS at all . . . yet.
Like it or not 2 turbos are the way the industry is going-Fiat and BM got there first (on 4 cyl engines) with their "23D" and JTD twin turbos, VW was slow, but now has a twin turbo 2.0 (not using it on passenger cars yet but will do soon).
And 2 turbos have transformed the 6 cyl diesel market, BM started, then Merc and now VW have followed suit-all 3 are locked in a power battle and VW's recently launched 2 turbo diesel 6 pushed it to 309PS/480LBS/FT BMW upped the figs on theirs to match.
Mercedes showed an SLK with a TRIPLE turbo version of their 3 litre diesel (third turbo sat in the V I think) and an SL with a 5 litre V8 diesel back in 2005. Dunno why theyve taken so 'kin long, but theyll be launching a triple turbo 3 litre soon.
Pity they never had the balls to build the diesel SL (would have been easy as it was a production engine) and pity the diesel SLK thats just gone on sale is only a 2.2 4 cyl . . . but it DOES have 2 turbos and makes amazing torque for its size (369LBS/FT !!), you can also get this engine in the S CLass now !
The PSA/Ford/LandRover/Jag diesel engine joint venture uses 2 turbos on the V6s and the V8s. The 2.2 4 uses 2 turbos as well, in all its guises (though theyre all underpowered-the highest output is 177, which cant even match BM's 2.0 single turbo!).
the tuning boxes for the Lancia Delta TT JTD offer 230bhp & 335lbs, and that's with no other mods (DPF ect), so some good potential
Exactly, a proper remap, exhaust and I/C mod would see around 300PS/450LBS/FT. I know you can see 283 odd PS with the GTB2256v (or whatever its called) from the 2.4, but I bet its more laggy than 2 turbos.
Btw2. Turbo is one of the most strained component on the turbocharged engine. I still don't know why would anybody mess up with freefloat + wastegated turbos instead of one quality VNT one on 1.9JTD.
All the more reason to split the load it takes between 2 units, rather than have one take it all !
Maybe you should write to Fiat Powertrain, BMW, VW Goup, PSA/Ford/Jag/Landrover etc and tell em theyre wasting theyre time with 2 turbo set-ups Yan.ko ? !