? for turbo gurus

[lookup]

how does a four stroke fair in higher elevation does it lose power like a two stroke and does the cylinder pressure decrease with elevation with turbo

 

[winter brew]

Anything without a turbo, about 3%/1000ft....with a turbo alot less, but still a slight loss, there is a formula but I don't know it. I'm far from a turbo guru, I'm sure someone can give a much more detailed answer.

 

[0007]

Everything loses power at higher elevation, Jet's included, that's just physic's
Turbo's just allow you to turn up the boost to compensate
The new McX kit's have a TCV (Turbo Control Valve) that works with an atmo sensor that turn's up the boost automatically
So yes they lose power, 2 stroke and 4 at the same rate

 

[SLEDtv.org]

Try hitting up VOHK he knows turbos inside and out..

re: elevation

SeaLevel=14.7psi

Air Density decreases at a rate of 2.9% - 3.0% for each 1000 ft. of elevation above Sea Level

Atmospheric Pressure @ 9000 feet = 10.5 psi
Pressure Loss = (14.5 - 10.5) = 4.0 (4.0/14.5) = 27.58 % @ 9,000 feet

I believe any motor unless forced induction will lose the same rate % of power based on atmospheric pressure drops regardless of the type.

Also here's another interesting tidbit of info, persoanlly at 14k feet you have the ability to put/generate only 72% of normal power

Altitude
Feet Meters % FTP
0 0 100%
1000 300 99%
2000 610 98%
3000 910 96%
4000 1220 95%
5000 1520 93%
6000 1830 92%
7000 2130 90%
8000 2440 88%
9000 2740 86%
10,000 3050 83%
11,000 3350 81%
12,000 3660 78%
13,000 3960 75%
14,000 4270 72%