[s-cars] RE:Wastegate spring tightening

[Steve Powers]

Mihnea:

> Pizzo, thanks for the input. My point is that these limits (boost and
> timing limits) depend on the backpressure generated by the exhaust. If the
> EM/turbo hot side/DP/exhaust are too small and acting as bottlenecks in
> terms of flow, thus if they produce high backpressure, it's gonna be good
> for getting high boost at low RPMs, but it's also gonna be a great way of
> getting pinging at the top end, which will automatically limit the power.
> All this is aside from all cold side efficiency considerations, if the
> turbo runs at 250k RPM and 0% efficiency with 28psi at the redline (the RS2
> isn't far from that with that much boost but it's just an example), then
> it's totally pointless to even consider running that much boost, nevermind
> your turbo won't even last for a couple of hours.

yup, it really boils down to the size of the "pipe" through the motor. it's real
easy to get develop high pressure in a straw. not so easy in a firehose.

Steve Powers
'95 Avant, w/ K26/27 pumping up a firehose