Originally Posted by footie
You are right, there is no true info on the engine only speculation which includes not only the current RS4 engine 420ps (not likely), RS4 with twin turbos 480ps (possible) right through to the S6 engine in a higher state of tune 480ps (possible).
I personally like the idea of the big V10 as it would allow the RS5 to bridge the gap between either the M3 or M6, but what would such a heavy engine not do to the handling and that includes the RS4 engine with turbos, it to would weigh quite a bit.
I have tried to read up as much on all the M3's rivals and future rivals and I read about something called Valvelift, have you heard of it and if so is it similar to BMW's Vanos system? If it something different is it possible that the RS5 could have the current RS4 engine only with this technology and what potential power gains could be had.
Sorry to put you on the shot like that.
If I understand it correctly Valvelift is a combination of BMW's VANOS (valve control) and Valvetronic (valve lift). What seems to be different is that Audi's Valvelift only controls the intake valve, whereas VANOS in its current stage also has a outlet control. The valve lift of both Audi's and BMW's systems however work on the intake valves only.
How much power gain that new Valvelift system would be good for? Don't know. Both Audi and BMW mention the lower fuel consumption: BMW claimed up to 10% for Valvetronic, Audi 14% for Valvelift.
Agree that it wouldn't be a good idea to feature the V10 in the RS5, the weight increase might be too big.
Best regards, south