RE: One-off Challenger Hellcat X announced

RE: One-off Challenger Hellcat X announced

Author
Discussion

xRIEx

8,180 posts

147 months

Tuesday 28th July 2015
quotequote all
RoverP6B said:
Well, an exhaust turbine just makes it a turbocharger, which is what we're trying to avoid...
But it doesn't matter as long as the turbine and the compressor can operate independently. An electrically driven compressor can still provide full boost from idle if required, whether the electricity to run it has come from braking energy recovery, an exhaust turbine or as a present from the king of the electricity fairies.

Edited by xRIEx on Wednesday 29th July 11:50

R8VXF

6,788 posts

114 months

Wednesday 29th July 2015
quotequote all
wormus said:
R8VXF said:
Would prefer to go with a Maggie heartbeat 2300, much better cooling than the Eaton.
They're all Eaton TVS rotor packs. Just a different case and intercoolers on the Heartbeat. Truth is the 2300 will only make about 850hp no matter what version you use, not on pump fuel anyway. God knows I've tried!
Sorry wormus, just wanted to pick you up on this. Just seen this this morning: http://www.hsvforum.com.au/showthread.php?14764-Ma...

and for an explanation of what makes the HB better than the TVS: https://www.youtube.com/watch?v=Z6gTQq6vn4w

wormus

14,497 posts

202 months

Wednesday 29th July 2015
quotequote all
R8VXF said:
Sorry wormus, just wanted to pick you up on this. Just seen this this morning: http://www.hsvforum.com.au/showthread.php?14764-Ma...

and for an explanation of what makes the HB better than the TVS: https://www.youtube.com/watch?v=Z6gTQq6vn4w
Sorry I don't understand what you are getting at. The heartbeat does make slightly more power but mainly because it has more efficient intercoolers. Otherwise they are exactly the same rotors in a different case. Better design, definitely but not a massive step up for most of us to warrant changing from the TVS2300 to the Heartbeat.


TVS2300 / heartbeat
2500rpm 210hp / 240hp
3000rpm 295hp / 315hp
3500rpm 345hp / 375hp
4000rpm 390hp / 435hp
4500rpm 435hp / 500hp
5000rpm 505hp / 565hp
5500rpm 600hp / 600hp
6000rpm 625hp / 650hp

Worthwhile but hardly amazing. Interesting comparison but I would have expected more of a difference.





Edited by wormus on Wednesday 29th July 17:53

RoverP6B

4,338 posts

127 months

Thursday 30th July 2015
quotequote all
xRIEx said:
But it doesn't matter as long as the turbine and the compressor can operate independently. An electrically driven compressor can still provide full boost from idle if required, whether the electricity to run it has come from braking energy recovery, an exhaust turbine or as a present from the king of the electricity fairies
It does matter. A turbine in the exhaust ruins the sound of the engine and adds a load of back pressure. An exhaust-driven compressor will always lag behind the engine itself. Even with electrical assistance to the turbocharger, you'll never get the transition from electric to engine power completely smooth...

xRIEx

8,180 posts

147 months

Thursday 30th July 2015
quotequote all
RoverP6B said:
xRIEx said:
But it doesn't matter as long as the turbine and the compressor can operate independently. An electrically driven compressor can still provide full boost from idle if required, whether the electricity to run it has come from braking energy recovery, an exhaust turbine or as a present from the king of the electricity fairies
It does matter. A turbine in the exhaust ... adds a load of back pressure.
So?


RoverP6B said:
An exhaust-driven compressor will always lag behind the engine itself.
The compressor isn't being driven by the exhaust gases, the turbine is. The turbine feeds a supercapacitor, the supercapacitor feeds the compressor.


RoverP6B said:
Even with electrical assistance to the turbocharger, you'll never get the transition from electric to engine power completely smooth...
What are you talking about? What "transition"?

RoverP6B

4,338 posts

127 months

Friday 31st July 2015
quotequote all
Back-pressure strangles the engine and ruins the sound. If you have an exhaust-driven turbocharger, that means a turbine in the exhaust manifold adding a load of back-pressure. The transition - if you spin the turbo up electrically, you're going to have to take that electric power off when the exhaust gas flow is sufficient to sustain the turbine RPM.

xRIEx

8,180 posts

147 months

Friday 31st July 2015
quotequote all
RoverP6B said:
Back-pressure strangles the engine and ruins the sound. If you have an exhaust-driven turbocharger, that means a turbine in the exhaust manifold adding a load of back-pressure. The transition - if you spin the turbo up electrically, you're going to have to take that electric power off when the exhaust gas flow is sufficient to sustain the turbine RPM.
Or have some sort of energy storage device, such as a supercapacitor or battery (or both).