High Altitude Dyno / Z1 400 hp kit notes
 

I have dyno results From sea level (ZcarGarage in San Jose California) and at 6000 feet (MAC Autosports in Parker Colorado.)

Stock dyno (base/reference dyno) in California: 293.6 whp/248.27 q
after JWT pop chargers, Berk HFC/CBE and tune: 318.20whp/265.33 q
Total improvement: +24.6whp/+17.06 q

At 6000 feet with tune (and same mods): 299.03 whp/???.?? q
At 6000 feet with Z1 400hp kit(Berk CBE)/tune: 317.84 whp/251.13 q
Total change: +18.81whp/???.?? q

Conclusion. Going from sea level to Colorado (5-6000 feet) you lose about 20 whp (roughly 25 crankcase hp)

also:
JWT pop chargers and Berk HFC/CBE gained me about 25 whp and Z1 400 hp kit did about 19 whp better still.

I'd guess Z1 kit total gain is +43.4 whp with humble gains in q due to removing cats (back pressure)

I just thought it was interesting.

Z1 kit (at sea level) would be (best guess) about 340 whp assuming 18% drive-line loss about 401.2 crank hp.

This is good info, Since I have your mods minus headers,

Sweet write up Cliff! Nice to see some real #'s.

I wonder if we can conclude that we lose 6% across the board even if going FI? I never believe the SAE correction on FI up here. It seems over inflated.

Maybe taking uncorrected #'s and adding 6% is more accurate.

That sounds about right.

Thanks for sharing :tiphat:

I had Stillen SC with 9lb pulley, only seen 7.2 cause of elevatio. I made 400 others with simular set up made 440-430.

sounds right. I'm 342 with Z1

Did you have the impeller upgrade also or just the regular?

Turbos are boosted to a certain pressure, so they are much more tricky to determine altitude losses. Theoretically they wouldn't lose power at altitude since they boost to a certain absolute pressure value, however thinner air requires them to spin faster causing more parasitic loss, as well as potentially overspinning and losing efficiency and power. Spool up time is also affected.
Superchargers are boosted based on engine RPM, so they suffer the same losses as NA cars at altitude.