flyrotary@lancaironline.net Mailing List Archive

Great overlay John.

For some reason you plots seem to put this more in the surge region than with the data that I was using. I don't know what the difference is. Anyway, based on your initial conditions I decided that maybe going a little smaller (moving the overlay to the right) would be OK. And what do you know, I have been following a turbo on e-bay with a compressor between the v-trim and p-trim (slightly smaller) and I may just get it for $335. And it has a nice way to attach the exhaust - unlike that lame TO4 I bought from someone on this list that has no way to attach the exhaust(slip fit turbo's are everywhere and they suck - anyone want to buy one?) :)

Dave Leonard

That's better Dave

I don't know Excel all that well, but I tried to make a few additions.

I added a graph overlayed on the compressor map, then generated some plots by iterative data entry.

There must be a way to generate the source data and plot it based on a table of MAP and altitude.

This would help get closer to knowing what settings keeps us on the "island".

Does this make any sense, or am I off on a wild goose chase?

Hmmm. A wild goose at 15000 ft while at 46 MAP and 6500 rpm. I wonder where that would go on the chart :)

Regards,

John