Factory SuperTurbo - W201 CDI - 190 D BlueEFFICIENCY
Factory SuperTurbo - W201 CDI - 190 D BlueEFFICIENCY
My apologies if this was already posted:
http://www.caranddriver.com/features/09q....6-feature
http://media.daimler.com/dcmedia/0-921-6...8875948531
http://www.theautochannel.com/news/2009/...76730.html
(03-18-2010, 04:16 PM)GREASY_BEAST Oh wow. I'd buy one....without the EGR and a VNT instead of the 1980's sequential turbos.
(03-18-2010, 04:16 PM)GREASY_BEAST Oh wow. I'd buy one....without the EGR and a VNT instead of the 1980's sequential turbos.
(03-18-2010, 05:21 PM)ForcedInduction ...without the EGR and a VNT instead of the 1980's sequential turbos.You lost me here. You're saying you don't approve of their use of sequential turbos? Seems to work pretty well from the factory. Probably worked like crap with mechanical controls in 1980. But they are not using 1980's technology, now are they. I could care less if it has EGR or not...
(03-18-2010, 05:21 PM)ForcedInduction ...without the EGR and a VNT instead of the 1980's sequential turbos.You lost me here. You're saying you don't approve of their use of sequential turbos? Seems to work pretty well from the factory. Probably worked like crap with mechanical controls in 1980. But they are not using 1980's technology, now are they. I could care less if it has EGR or not...
(03-18-2010, 05:26 PM)gsxr You're saying you don't approve of their use of sequential turbos?No. Its antiquated technology to solve a problem that a VNT turbo does better.
Quote:Probably worked like crap with mechanical controls in 1980.All the sequentials of the 80's were computerized (Mazda, Toyota, Subaru).
Quote:I could care less if it has EGR or not.Except that its recirculating nearly 50% of the exhaust back to the intake.
(03-18-2010, 05:26 PM)gsxr You're saying you don't approve of their use of sequential turbos?No. Its antiquated technology to solve a problem that a VNT turbo does better.
Quote:Probably worked like crap with mechanical controls in 1980.All the sequentials of the 80's were computerized (Mazda, Toyota, Subaru).
Quote:I could care less if it has EGR or not.Except that its recirculating nearly 50% of the exhaust back to the intake.
(03-18-2010, 05:46 PM)ForcedInduction(03-18-2010, 05:26 PM)gsxr You're saying you don't approve of their use of sequential turbos?No. Its antiquated technology to solve a problem that a VNT turbo does better.
The only reason the engine makes more rated HP and torque than a comparable VNT engine is that the turbos work as a compound for a brief period. In single mode (off idle and upper RPMs) it makes no more power than a VNT engine.
They used two turbos because of cost, they have to keep the diesel option reasonably close to the g@sser option or people won't want to buy them. Its cheaper to manufacture two normal turbos and associated parts than to cast, machine, weld and assemble a turbo with 15+ small inconel moving parts and a computerized actuator to control it.
(03-18-2010, 05:46 PM)ForcedInduction(03-18-2010, 05:26 PM)gsxr You're saying you don't approve of their use of sequential turbos?No. Its antiquated technology to solve a problem that a VNT turbo does better.
The only reason the engine makes more rated HP and torque than a comparable VNT engine is that the turbos work as a compound for a brief period. In single mode (off idle and upper RPMs) it makes no more power than a VNT engine.
They used two turbos because of cost, they have to keep the diesel option reasonably close to the g@sser option or people won't want to buy them. Its cheaper to manufacture two normal turbos and associated parts than to cast, machine, weld and assemble a turbo with 15+ small inconel moving parts and a computerized actuator to control it.
(03-20-2010, 06:02 AM)Kiwibacon You cannot replace two staged turbos with a VNT and get anything near the torque curve.Yes you can, its exactly what Ford did with the 6.4L. Well matched VNT for instant low-end and throttle response with a large non-wastegated turbo for power.
Quote:As you optimise a compressor for higher pressure ratios, the map gets narrower. As you optimise them for a wider map, the available pressure ratios drop.Holset does both very well. Garrett, IHI and Borg's issue is they don't use something like Holset's map width enhancement on their small turbos, just 76mm and up.
Quote:If you think there is a single compressor that can suit this engine, please find the map and show us. With the operating range plotted.Holset doesn't publicly distribute their maps.
(03-20-2010, 06:02 AM)Kiwibacon You cannot replace two staged turbos with a VNT and get anything near the torque curve.Yes you can, its exactly what Ford did with the 6.4L. Well matched VNT for instant low-end and throttle response with a large non-wastegated turbo for power.
Quote:As you optimise a compressor for higher pressure ratios, the map gets narrower. As you optimise them for a wider map, the available pressure ratios drop.Holset does both very well. Garrett, IHI and Borg's issue is they don't use something like Holset's map width enhancement on their small turbos, just 76mm and up.
Quote:If you think there is a single compressor that can suit this engine, please find the map and show us. With the operating range plotted.Holset doesn't publicly distribute their maps.
(03-20-2010, 06:12 AM)ForcedInduction(03-20-2010, 06:02 AM)Kiwibacon You cannot replace two staged turbos with a VNT and get anything near the torque curve.Yes you can, its exactly what Ford did with the 6.4L. Well matched VNT for instant low-end and throttle response with a large non-wastegated turbo for power.
With their sequential system they get a big rush of torque from compound mode then it falls on its ass (relatively) as it goes to big single mode.
Quote:As you optimise a compressor for higher pressure ratios, the map gets narrower. As you optimise them for a wider map, the available pressure ratios drop.Holset does both very well. Garrett, IHI and Borg's issue is they don't use something like Holset's map width enhancement on their small turbos, just 76mm and up.
Quote:If you think there is a single compressor that can suit this engine, please find the map and show us. With the operating range plotted.Holset doesn't publicly distribute their maps.
(03-20-2010, 06:12 AM)ForcedInduction(03-20-2010, 06:02 AM)Kiwibacon You cannot replace two staged turbos with a VNT and get anything near the torque curve.Yes you can, its exactly what Ford did with the 6.4L. Well matched VNT for instant low-end and throttle response with a large non-wastegated turbo for power.
With their sequential system they get a big rush of torque from compound mode then it falls on its ass (relatively) as it goes to big single mode.
Quote:As you optimise a compressor for higher pressure ratios, the map gets narrower. As you optimise them for a wider map, the available pressure ratios drop.Holset does both very well. Garrett, IHI and Borg's issue is they don't use something like Holset's map width enhancement on their small turbos, just 76mm and up.
Quote:If you think there is a single compressor that can suit this engine, please find the map and show us. With the operating range plotted.Holset doesn't publicly distribute their maps.
(03-20-2010, 06:30 AM)Kiwibacon Ford have not yet produced any engine running in anything near the boost levels of the german car diesels.I'm sorry, exactly what cars are running more than 42psi of sustained (NOT peak!) boost pressure like Ford? How many of them can be modified to run 55psi of sustained boost using stock parts?
Quote:Plot 42psi boost out on any compressor map and you'll see really quickly why single compressors can't fly.I'm sorry, but you're missing the entire point of this debate.
Quote:The BMW 6 runs more than 42psi boost.For only 1500rpm of the 4800rpm revv range, then it falls flat to only 22psi.
Quote:How do you know holset does it well if you can't provide the maps?The fact they work as advertised.
(03-20-2010, 06:30 AM)Kiwibacon Ford have not yet produced any engine running in anything near the boost levels of the german car diesels.I'm sorry, exactly what cars are running more than 42psi of sustained (NOT peak!) boost pressure like Ford? How many of them can be modified to run 55psi of sustained boost using stock parts?
Quote:Plot 42psi boost out on any compressor map and you'll see really quickly why single compressors can't fly.I'm sorry, but you're missing the entire point of this debate.
Quote:The BMW 6 runs more than 42psi boost.For only 1500rpm of the 4800rpm revv range, then it falls flat to only 22psi.
Quote:How do you know holset does it well if you can't provide the maps?The fact they work as advertised.