Thoughts on Audi RS4 (B7) - Supercharged to 600bhp!

[jackpe]

Driving one tomorrow.. always liked them but never tried one before. This one has a supercharger kit bringing power up to 600bhp.. so it should be somewhat of a monster!

[trickywoo]

It'll be quick but if thats crank HP it'll be well down at the wheels compared to an N/A or turbo car putting out that figure.

[OverSteery]

trickywoo said:

It'll be quick but if thats crank HP it'll be well down at the wheels compared to an N/A or turbo car putting out that figure.

Care to explain why transmission losses are affected by a supercharger (compared to a turbo or N/a)

[Vitorio]

OverSteery said:

Care to explain why transmission losses are affected by a supercharger (compared to a turbo or N/a)

It wont be

the AWD driveline will cost a bit more in transmission losses, and comparing a 600hp (at the crank) car to a 600hp (at the wheels) car will obviously make a significant different

[trickywoo]

Vitorio said:

OverSteery said:

Care to explain why transmission losses are affected by a supercharger (compared to a turbo or N/a)

It wont be

the AWD driveline will cost a bit more in transmission losses, and comparing a 600hp (at the crank) car to a 600hp (at the wheels) car will obviously make a significant different

Aren't you powering one air pump with another air pump i.e. supercharger takes likely 100 bhp to run. I appreciate I may have the wrong end of the stick as regards actual crank power and corrected crank power as of course the supercharger is run off the crank and you can't have one without the other.

[Vitorio]

trickywoo said:

Aren't you powering one air pump with another air pump i.e. supercharger takes likely 100 bhp to run. I appreciate I may have the wrong end of the stick as regards actual crank power and corrected crank power as of course the supercharger is run off the crank and you can't have one without the other.

I cant imagine anyone would list crank power on a SC engine without taking the SC into account, there is no real way to even measure it without powering the SC by a different powersource.

crank/flywheel power is the amount of power the engine transmits into a gearbox/driveshaft

[jackpe]

Here's the dynosheet guys...

[J4CKO]

Just make sure it has been done well, could be a world of pain and those engines have issues with carbon build up, get it checked by someone who knows engines if you dont, might have blow by or other nasties.

It may well be fine, but it was a high performance engine, that has had another 150 plus bhp released, real life isnt like Forza and more power can bring more issues, may well be fine but needs expert inspection.

Its its ok, will be very, very quick.

[IanH755]

J4CKO - Normally you'd be 100% right regarding the awful carbon build up on this engines when they are still NA (it's pretty poor really) but FI'ing the FSI V8 really minimises the carbon build up significantly. The same is also true for the V10 (NA FSI S6 vs FI TFSI RS6) which we found when I had my FI RS6 Carbon Cleaned at 94k miles.

[Uggers]

I'd stick to standard, that way you can just pay ludicrous amounts out for repairs regularly instead of all the time

[J4CKO]

IanH755 said:

J4CKO - Normally you'd be 100% right regarding the awful carbon build up on this engines when they are still NA (it's pretty poor really) but FI'ing the FSI V8 really minimises the carbon build up significantly. The same is also true for the V10 (NA FSI S6 vs FI TFSI RS6) which we found when I had my FI RS6 Carbon Cleaned at 94k miles.

Ah ok, cheers ! I did ponder whether it makes any difference to that, there you have it, to avoid engine bother, fit a supercharger ! chaps, you can justify the charger install to the missus as a preventative measure.

Still, would be a bit cautious.

[Escort3500]

Uggers said:

I'd stick to standard, that way you can just pay ludicrous amounts out for repairs regularly instead of all the time

but true.

They're quite expensive to run (though probably much the same as comparable cars). For those buying an older (B7) RS4 and asking on the RS246 forum, I always suggest having a slush fund for inevitable big bills (DRC, brakes, oil cooler pipes etc). Some manage to scrape together just enough to buy, tax and insure one, then fall out of love with it when it goes wrong and they haven't got the spare dosh to fix it.

[jackpe]

Ha!! I'm not buying it, it's just to try it.. i'll make a youtube video so you can see what I think once i've driven it!

[anonymous-user]

the rs4 was notoriously reported hp, some 100 down on figure, so 600bhp is very optimistic. i would get the s4 supercharged add a few mods and looking at a proper 500 bhp.

[jackpe]

The Spruce goose said:

the rs4 was notoriously reported hp, some 100 down on figure, so 600bhp is very optimistic. i would get the s4 supercharged add a few mods and looking at a proper 500 bhp.

You've seen the dyno print out from a previous post right?? It does make 600bhp.

[J4CKO]

jackpe said:

The Spruce goose said:

the rs4 was notoriously reported hp, some 100 down on figure, so 600bhp is very optimistic. i would get the s4 supercharged add a few mods and looking at a proper 500 bhp.

You've seen the dyno print out from a previous post right?? It does make 600bhp.

Yeah, standard ones never seem to make the 420 bhp though, 360 to 380 seems typical, with quite high drivetrain losses, not slow obviously but the old N/A stuff seems to be nowhere near all the newer turbo stuff which tends to be underratted from the factory. Still a fast car but perhaps not quite as mad as it would seem a supercharged one should do the trick though.

[Escort3500]

J4CKO said:

jackpe said:

The Spruce goose said:

the rs4 was notoriously reported hp, some 100 down on figure, so 600bhp is very optimistic. i would get the s4 supercharged add a few mods and looking at a proper 500 bhp.

You've seen the dyno print out from a previous post right?? It does make 600bhp.

Yeah, standard ones never seem to make the 420 bhp though, 360 to 380 seems typical, with quite high drivetrain losses, not slow obviously but the old N/A stuff seems to be nowhere near all the newer turbo stuff which tends to be underratted from the factory. Still a fast car but perhaps not quite as mad as it would seem a supercharged one should do the trick though.

Audi quoted 414 bhp but in reality they were around 400 from the factory. Carbon build up saps the power over time however. Mine was producing 367 bhp when it went to MRC and 427 after a carbon clean and stage 2 map.

[anonymous-user]

take it to an independent rr it won't make 600bhp. these tuning companies love to overstate bhp, that is why they sell. 500 bhp i would say max, like i said a s4 would be my call.

have a read around the real bhp for rs4 was around 360bhp.

Edited by The Spruce goose on Tuesday 28th March 22:07

[AppleJuice]

Escort3500 said:

Audi quoted 414 bhp but in reality they were around 400 from the factory. Carbon build up saps the power over time however. Mine was producing 367 bhp when it went to MRC and 427 after a carbon clean and stage 2 map.

and:

The Spruce goose said:

take it to an independent rr it won't make 600bhp. these tuning companies love to overstate bhp, that is why they sell. 500 bhp i would say max, like i said a s4 would be my call.

have a read around the real bhp for rs4 was around 360bhp.

Edited by The Spruce goose on Tuesday 28th March 22:07

/thread

PS: Why not get a C6 RS6 and be done with it? 580PS out of the box, even if the steering is reportedly a bit wooden (haven't driven one, sorry).

[jackpe]

Right, so i've driven it and it is properly mental!
To all the naysayers, MRC are respected tuners and the dyno sheet shows before and after curves and figures, standard output on the same dyno was around 370hp.. with the kit fitted on same dyno 607hp.

In any case it was the fastest thing I've ever driven and ridiculously violent punching out of corners.

Moderator edit: no promoting your YouTube channel please.

Edited by jeremyc on Friday 31st March 12:17