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Discussion Starter · #1 ·
Having joined the Fortitude site ... a huge forum and news article based site ... I have taken the liberty of posting a thread in their R8 section ... here ... asking any members there is they can post updates here ... if they have time.

So, hopefully some of them will join here and help keep the information flowing here.
 

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Paul,

Thats a perfect post. Thanks for taking the time to make it and hopefully our little community here can benefit from a site dedicated entirely to the Audi R8.
 

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Discussion Starter · #5 ·
Same engine ... same horse power... same rev limit - I can testify to this from finding the limiter in my RS4 and having the specs to hand.

As TTej has pointed out, it's using a dry sump ... one of hte most important benefits of a dry sump if the ability to mount it lower down in the engine bay and help keep the centre of gravity as low as possible.

I'm not sure if the torque curve will be improved ... it's pretty impressive already. But, not knowing huge amounts about dry sump engines I don't know if it changes how the power is delivered, I wouldn't think so ... but I'm not certain.
 

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in the photos of the leaked internal documents shows the r8 has 420 bhp but the rs4 only has 414
Well there is your answer but are you sure they are both stating BHP, as PS is something different as they sometimes use that aswell.
 

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Very cool video, I am addicted to the micro-site. What great advertising, especially being able to pick out your colors.
you know there is actually 8 at launch and not just the 4 on the microsite. have you sent off for the screensaver. i keep looking at my phone aswell!
 

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I'm not sure if the torque curve will be improved ... it's pretty impressive already. But, not knowing huge amounts about dry sump engines I don't know if it changes how the power is delivered, I wouldn't think so ... but I'm not certain.
I believe a dry sump also keeps the reciprocating weight of oil down on the crankshaft. Similar to what you would normally use a crank scraper for, but is unecessary on a dry sump system.
 

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Re: Fortitude thread - Horsepower

Some confusion here !

Both RS4 and R8 are quoted as 414 BHP. This corresponds to 420 PS.

(PS is the metric unit for horsepower. German: Pferde = Horse)
 

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Discussion Starter · #13 ·
Re: Fortitude thread - Horsepower

Some confusion here !

Both RS4 and R8 are quoted as 414 BHP. This corresponds to 420 PS.

(PS is the metric unit for horsepower. German: Pferde = Horse)
Even more confusion after putting my RS4 on a rolling road at the weekend and having the calculated flywheel power (bhp) measured at 340bhp!

I know you're going to lose some horses as the car ages, but when many cars tested that day had lost very few horses from teh engine bay over three times as many years as months that I've owned the RS4 ... I think I'll be speaking to Audi when I have a bit of spare time!
 

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Discussion Starter · #15 ·
Although the Audi UK site contains the following text:

"Mid-mounted 4.2-litre V8 FSI petrol engine delivers 420PS at 7,800rpm and 430Nm from 4,500 to 6,000rpm"

Quoted information to be found on audi.co.uk

Which puts it at the same power rating as the RS4 as the Audi UK site also contains the following text:

"4.2 litre engine growls like a V8 should. You engage gear. 420PS and 430Nm of torque are waiting."

Quoted information to be found on audi.co.uk

Seems even Audi can't even agree with themselves!
 

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Re: Fortitude thread - Horsepower

Even more confusion after putting my RS4 on a rolling road at the weekend and having the calculated flywheel power (bhp) measured at 340bhp!

I know you're going to lose some horses as the car ages, but when many cars tested that day had lost very few horses from teh engine bay over three times as many years as months that I've owned the RS4 ... I think I'll be speaking to Audi when I have a bit of spare time!
But Paul Rolling Roads are a bit of a black art, are you sure it was the power at the flywheel and not at the wheel itself so then taking into account transmission loss.??
 

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Discussion Starter · #17 ·
Re: Fortitude thread - Horsepower

But Paul Rolling Roads are a bit of a black art, are you sure it was the power at the flywheel and not at the wheel itself so then taking into account transmission loss.??
I know they were calculating figures at the flywheel correctly (to within a reasonably small tolerance) as I was there with a group of fellow NSX owners and the results of all tests clearly show the equipment (professionally run and clibrated) was not giving duff readings.

The operator did say that a lot of modern cars, with all the electronic wizardry often won't let the car have full power when runn on the rollers ... he's not sure exactly why, but he says he has seen it frequently on other modern cars. Pressing the sport button only loosens the traction control, improves throttle response and opens some baffles in the exhaust on the RS4. So, some of the controlling electronic systems would still be turned on, to some varying degree.

I'll be speaking to Audi when I get the chance, needless to say I'd like the engine to be running over 400bhp at the flywheel.
 

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An interesting thing i was speaking to AmD about was transmission loss.

The boxster looses about 20 BHP where as the Quattro cars can loos nearly 80bhp!

with the engine right above the rear wheels i was hoping the R8's loss would be allot less.
 

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It seems people are still confused (including Audi leaflets !) regarding PS and BHP, RS4 output and R8 output.

OK. If you want to compare the two, then forget PS & BHP. Just look at the published Kilowatt output. You will find that both RS4 and R8 are listed as 309 Kw.

Just seems that there is accidental use of BHP when then mean PS and vice-vera.

Paul, regarding your power measurement. Some rolling roads back-calculate flywheel power assuming certain transmission loses, and this is where is can go wrong with a 4WD car.

Also, quoted power outout is with 98 RON super-unleaded. Do you use standard or super ?

The reading you were given are plain wrong, otherwise your car is in a seriously BAD condition !

I have an original RS4 and went to Germany to have it "chipped" by MTM from 380 BHP (standard spec) to 420 BHP. Their rolling road before-and-after readings agreed with the literature.

(got to 179 mph on the way back to UK !!!)

If you want to re-test go to an Audi specialist tuner in UK such as Kim Collins.

Cheers.
 

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Discussion Starter · #20 ·
R8 England said:
Also, quoted power outout is with 98 RON super-unleaded. Do you use standard or super ?
Only ever used Shell Optimax, or BP Ultimate, since Shell V-Max has been out, I've been using that. No point in having a powerful car and putting a weak fuel in it.
R8 England said:
I have an original RS4 and went to Germany to have it "chipped" by MTM from 380 BHP (standard spec) to 420 BHP. Their rolling road before-and-after readings agreed with the literature.

(got to 179 mph on the way back to UK !!!)
WOW! For an estate, that's seriously quick!
R8 England said:
The reading you were given are plain wrong, otherwise your car is in a seriously BAD condition !

If you want to re-test go to an Audi specialist tuner in UK such as Kim Collins.
Yeah, it's obvious the readings are wrong.
I think I'll see if I can find an Audi specialist tuner somwhere nearby and get it re-tested. At least they didn't charge for the run ... which as the results were not worth the paper they were printed on was only right ... but good of them to waive the charge after the run was made.
 
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