Thread: higher altitudes
07-28-2008, 09:44 PM #1
When running at higher than normal altitudes say from a norm of 800' to say 1500-2500 and higher.
What changes would I notice?
07-28-2008, 09:53 PM #2
VaRedneck, you will loose about 15 hp. Enough to notice a decrease in acceleration and probably a couple of mph.
07-28-2008, 09:53 PM #3
VaRedneck, i will give you a senerio in comparing my riding conditions to Dallas.
2,500 ft elevation with RAD of 5,000 ft.
with stock 15/22 i can turn prop to 7,800 rpm.
with 15/20 +1 mm with 83 mm ring runs 8,100 rpm and 11.4 to 11.5 psi boost.
aprox 500 ft and aprox RAD of 1,500 to 2,000 ft.
with stock 15/22 (exact same setup) turn prop to 8,060 rpm.
with 15/20 +1 mm with 81 mm ring all over the limiter at 8,150 to 8,200 rpm so cant really say what rpm increase but big time on limiter. boost was 11.8 to 11.9 psi
A good rule of thumb is 100 rpm loss for every 1,000 ft increase in actual elevation. Of course heat plays a big role. My figures are both at high temp close to 100 degrees.
I see a difference of 200 to 250 rpm and .5 in boost numbers. That is with aprox 2,000 ft difference.
I know way to much about elevation power reduction.
I will be riding in Dallas again this weekend and will be running 15/22,s in both skis, so hopefully will have the rxp running better.
Last edited by skoepp; 07-29-2008 at 12:25 AM.
07-29-2008, 04:51 AM #4
A while back I was all over the limiter....I stiffened things up a bit and lost a 3-400 rpms.
I'll set it back to what I ran last fall and see how she does.
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