New RS5 Coupe
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Interesting that they have taken the 2.9L V6 from the Porsche Panamera rather than upgrade further the 3l V6 in the S5...I wonder what that says for the S5 unit. They have more or less the same capacity so I'd be fascinated to understand what separates them. Clearly a second turbo-charger, but what else
http://youwheel.com/home/2016/07/05/brief-analysis-the-2017-porsche-panameras-2-9l-turbo-v6-engine/
http://articles.sae.org/14923/
The Porsche designed engine looks to be fundamentally different to the Audi 3.0 item. And is the 4.4 V8 engine with 2 cylinders chopped off.
Plasma coated cylinder liners instead of iron will help to reduce weight along with a lot of other weight saving measures. Hopefully this won't make the engine fragile if pushed a bit.
It looks to have a water to air intercooler system rather than traditional air/air intercoolers that are used on the 4.4 v8 Panamera twin turbo. That may hinder extra power unless modified. Probably another way to lose some weight. Still looks to have very capable performance out of the box.
The engine below is the 4.4 V8 Porsche engine, you can see some of the similarities.
I like the interior, looks very uncluttered compared to a lot of cars these days. Not sure about the front end styling.
It goes sideways as well by the look of it, has a hooligan mode
.
http://www.roadandtrack.com/car-shows/geneva-auto-show/news/a32846/2018-audi-rs5-geneva/
http://articles.sae.org/14923/
The Porsche designed engine looks to be fundamentally different to the Audi 3.0 item. And is the 4.4 V8 engine with 2 cylinders chopped off.
Plasma coated cylinder liners instead of iron will help to reduce weight along with a lot of other weight saving measures. Hopefully this won't make the engine fragile if pushed a bit.
It looks to have a water to air intercooler system rather than traditional air/air intercoolers that are used on the 4.4 v8 Panamera twin turbo. That may hinder extra power unless modified. Probably another way to lose some weight. Still looks to have very capable performance out of the box.
The engine below is the 4.4 V8 Porsche engine, you can see some of the similarities.
I like the interior, looks very uncluttered compared to a lot of cars these days. Not sure about the front end styling.
It goes sideways as well by the look of it, has a hooligan mode
.http://www.roadandtrack.com/car-shows/geneva-auto-show/news/a32846/2018-audi-rs5-geneva/
Very interesting article thanks. The remark at the end is that it will be more laggy than the S5 due to dual turbos is interesting. We'll see if the journos pick up on that in reviews
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Scottyg
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The interior looks like a classier version of the new Audi Cockpit. More streamed and not as much fuss. I like.
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That is rather the key point. When you look into new model development it is clear that references are made to the old one. In the case of the B9 S5 it has a new turbo engine which would be referenced to the supercharged engine of the B8. Consider Audi's own words in SSP925803:
Pros and cons of a mechanical supercharging system with Roots blower compared to an exhaust turbocharging system
Pros:
– Charge pressure is immediately available whenever it is required
– Charge pressure is continuously supplied and rises with increasing rpm
– The charge air does not have to be cooled as much as turbocharged air
– Long life and maintenance-friendly operation
– Compact design (to save space, the supercharger can be installed in place of the intake manifold inside the V shaped area between the cylinder banks)
– High fuel efficiency
– Quick and dynamic torque response; peak torque is available at low rpm, providing good starting performance
– The compressed air paths to the cylinders are very short, resulting in a very low air volume and extremely quick response
– Enhanced exhaust emission characteristics (reason: the catalytic converter reaches its operating temperature faster). In an exhaust turbocharged engine, a portion of the heat energy is wasted in driving the turbocharger
Cons:
– It is very difficult to produce because very close manufacturing tolerances have to be maintained (rotor to housing and rotor to rotor)
– Higher susceptibility to ingress of foreign matter into the filtered air tract
– Relatively high weight
– Extensive soundproofing is needed
– Some engine power is lost in driving the blower
So I'm fairly sure that one of the design remits for the new 3.0 TFSI was that it must not detract too much from those benefits (in red) that the previous engine has. I will also guess that Audi was not pleased that it was relatively easy to tune the B8 S5 the same performance as the B8 RS5 and so for the new B9 S5's engine to be not so easily tuned would have been fine for Audi management.
From what I have read, Audi succeeded in their primary design remit. Other than using the obvious hot-V and twin-scroll turbo method of reducing lag, they also decided to have a high CR (for a turbo engine) and then use variable valve timing to introduce the Atkinson cycle to avoid the problems that high CR and high boost would cause at higher revs. I have yet to find confirmed data but I did read one article that the boost in the B9 engine is 1.3 bar, which is already quite high by OEM standards.
So to answer your first point, for the above reasons the capacity to tune the 3.0 TFSI engine for significantly more power is limited. For the sort of power that Audi want for an RS5 they had to go back to the more traditional route of lower CR and high turbo airflow. This is best done with dual monoscroll turbos, and thus we have the 2.9 biturbo. It can achieve more power than the 3.0 TFSI (and likely tuners will be able to uprate those turbos to achieve really high power), but of course this will be at the cost of turbo lag.
Really interesting thanks for that. I bet Revo et al, are working hard on tuning remaps as we speak so will be interesting to see if they get similar gains to the past or not in reality. I do wonder how big a deal Audi takes tuning, as I guess its a minority of customers that do it, and surely for most the risks (warranty, components failing) is enough to keep it to a few brave souls...?
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Some more info in link below
http://www.audi-sport.net/xf/threads/all-new-audi-rs-5-coupe-takes-charge-at-geneva.314690/
http://www.audi-sport.net/xf/threads/all-new-audi-rs-5-coupe-takes-charge-at-geneva.314690/
Hmmmm....yea I would be a bit disappointed as it now sounds very similar to my S5....which I guess should be obvious since it's now a 2.9 V6
When you compare it to the old B8.5 4.2 V8....yea I know which I prefer...
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It sounds lame and having your fun between 3 and 6.5k is no fun at all. Lots of changes and no crisp DCT to do them. I'm out. Going to cost me because when i change it will be have to be a 2 seater and a estate/SUV now not an RS4 which was both my needs/wants in 1 car. Or i just keep it because it will probably not lose money like it would have if the new one was good.
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