Nissan Titan XD Forum banner

1 - 11 of 11 Posts

·
Registered User
Joined
·
608 Posts
Discussion Starter #1


The turbo-diesel V8 engine in the next generation Titan will have a new two-stage turbine unit developed jointly by Cummins and Nissan. The new design will help to reduce lag, generate more low end torque, and deliver smoother transitions between low and high rpm.The new turbine unit uses a Holcet turbo with new Rotary Turbine Control (RTC). This shunts the exhaust gases in various modes to optimize emissions or power depending on what you need.

The RTC system has 4 operating modes. First is High-Pressure mode. This mode uses both stages and minimizes lag for a better response when shifting gears. Low Pressure mode cuts out the first stage to provide greater power output. There is also a Wastegate mode which provides maximum power output, and a Regen mode that helps the engine comply with emissions standards.

 

·
Registered User
Joined
·
340 Posts
In laymans, non marketeering speak: at lower engine speeds the valve directs exhaust into the smaller turbine which spools faster, as RPM's increase the valve begins to open and allow exhaust into the larger turbine, at high engine speeds the valve flips channelling all exhaust into the larger...
 

·
Registered User
Joined
·
608 Posts
Discussion Starter #5
Is this technology radically different from how other diesel engines work? Is this a major innovation or is it just some type of minor tweak and tune?
 

·
Registered User
Joined
·
340 Posts
ideologically its not radically different from multivane turbo setups. Perhaps there is more efficency involved but I think the trade off may be more moving components...???
 

·
Registered User
Joined
·
608 Posts
Discussion Starter #7
So its really making an existing technology more efficient? And it also looks really nice for those of us who care what things look like under the hood.
 

·
Registered User
Joined
·
81 Posts
It might help if they have a video or something where they talk about this engine and what it's like compared to others.
 

·
Registered User
Joined
·
340 Posts
It might help if they have a video or something where they talk about this engine and what it's like compared to others.
Its fairly simple actually. There is an electronically controlled butterfly valve that sits between the inlets for both turbos. ECU determines which inlet takes precedent. At low RPM flow is channelled into the smaller turbo which will spool much quicker from the reduced flow. As load/RPM increases the valve begins to shift over until the larger turbo takes precedent...
 

·
Registered User
Joined
·
857 Posts
Its fairly simple actually. There is an electronically controlled butterfly valve that sits between the inlets for both turbos. ECU determines which inlet takes precedent. At low RPM flow is channelled into the smaller turbo which will spool much quicker from the reduced flow. As load/RPM increases the valve begins to shift over until the larger turbo takes precedent...
Great, thanks for explaining it.
 
1 - 11 of 11 Posts
Top