proper fueling and tuning are not available yet in a finished product form...

The fact that we can run with or beat the off the shelf K04 tuner cars with tweaked K03 stuff tells you something about the turbos. It's only a matter of time before someone goes balls out on a set of K16's.

i'm sure Mike2kS4 or Verruckt can elaborate

NOT.

I seem to recall pictures a while ago showing the different blade shapes on the turbines...

and yes there is a difference in design, but the K04/16's compressor wheel is larger as well. The K04 wheel is an 8 fin while the k16 is a 12 fin design. The design of the K16 wheel is more efficient than the K04, flowing more air at a lower shaft speed as well.

I launch at the track at 3500rpm and shred all 4 tires. I can't get the bastage to hook! In cruising you can get into boost at any RPM off idle.

It hits so hard I snapped my car sideways a couple times in 4th/3000rpm in the rain rolling on the throttle 50% or so.

I need to finish my cat-back this week... Then I can get it on the dyno... I'm an A6er trying to catch up w/ you S4's and your crazy mods.

btw what KO4/16 type are you running. KO4 or KO3 housing?

when going with the K16 hybrids? slower boost ramp up, but less restriction in the higher rpm ranges.....so what's best for a street driven car? Not a track car, not a dyno queen.

TIA

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I hope this isn't too dumb a question, but I'm having a little trouble with the terminology here. Spool-up seems like a good description of the rpm vs boost relationship you have on your chart. It seems to me there is another parameter that I think of as lag. If you are cruising at a fairly low rpm and suddenly floor the gas, there is a time delay before you are pushed back in the seat. This doesn't seem to be quantified by a rpm vs boost chart. Am I correct in thinking of this as a different characteristic? I've seen the terms used interchangably here on AW, which has me confused. If so, I would guess that a heavier wheel with more backpressure might react more slowly than a lighter one in the situation I describe.

thanks,
Dave

lag is basically the time it takes for the turbo to "spool up" and create the requested boost. Once you start to make boost is when you begin to be "pushed back in your seat" ;)

although it's not totally correct. The "lag" as you describe it is slightly more than K04's, but you are not going to notice it at all unless you are doing side by side pulls with a K04 car.

your a/f ratio is correct for the given boost and spark is pushed to the threshold, there's nothing more that other software could do for you, right? That's why people running k03 x/xr are as fast or faster than the tuned k04 programs. When the air, fuel, and spark are right -- it's tuned. It can't be 'more' tuned. (of course this discussion disregards, part throttle, driveability, cold starts, etc.)