RS5 V8 vs R8 V8 - differences?

[200Plus Club]

Watching a tv prog it showed a 2014 RS 5 and stated the power at 440bhp I believe. Given the earlier R8 were 414 to 430bhp what's the difference in outputs down to? Remap or other tweaks?

[Rich_W]

Well the first two are the R8 is dry sumped. And obviously has a different exhaust.

That makes a difference straight away.

[Stuart1961]

The V8 in the R8 is the same engine as the RS4, whereas the RS5 is a different engine.

[200Plus Club]

Ah ok

[djc206]

Stuart1961 said:

The V8 in the R8 is the same engine as the RS4, whereas the RS5 is a different engine.

I wouldn't want to be quoted on this but I believe the R8 V8 is the same engine as the B7 RS4 but modified (This would figure since they're from the same era).

The RS5 and B8 RS4 Avant have the same engine which is based on the 5.2 V10 with a couple of cylinders shaved off the end so different to the R8's. I'm 99.999% certain the RS5 and newer RS4 are the same engine as I've owned both.

[Rich_W]

Stuart1961 said:

The V8 in the R8 is the same engine as the RS4, whereas the RS5 is a different engine.

I'm all ears. Since I'm sceptical.

R8 4.2
R8 has 2 ECUs
R8 has 2 throttle body's and a different intake system Bizarrely both TBs go into 1 chamber.
R8 is obviously Dry Sumped
Exhaust and Cats are different.






RS4 4.2
Only 1 throttle body
Different intake
Wet Sump
1 Ecu



RS5 later V8

Twin TB
Sort of a halfway house
Wet Sump
1 ECU

[200Plus Club]

Interesting thanks

[Dr G]

...also; anyone ever seen one of these V8s make their quoted power without modification?

[200Plus Club]

Yes I heard that. Carbon coking up also a factor apparently. R8 feels quick was just wondering if a simple tweak might be had etc.