Return-Path: Received: from smtpauth03.mail.atl.earthlink.net ([209.86.89.63] verified) by logan.com (CommuniGate Pro SMTP 4.2.5) with ESMTP id 573980 for flyrotary@lancaironline.net; Mon, 20 Dec 2004 09:41:08 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.86.89.63; envelope-from=Dastaten@earthlink.net Received: from [24.238.206.157] (helo=earthlink.net) by smtpauth03.mail.atl.earthlink.net with asmtp (Exim 4.34) id 1CgOiC-0003tu-LF for flyrotary@lancaironline.net; Mon, 20 Dec 2004 09:40:36 -0500 DomainKey-Signature: a=rsa-sha1; q=dns; c=simple; s=test1; d=earthlink.net; h=Message-ID:Date:From:Reply-To:User-Agent:X-Accept-Language:MIME-Version:To:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding; b=EFA6hJ1IAd7ALTheC7b19soPXktfFVcwS9t2Pef2d11iiTZDhHUn4S9RpnH3kB1x; Message-ID: <41C6E3E6.6030801@earthlink.net> Date: Mon, 20 Dec 2004 08:38:30 -0600 From: David Staten Reply-To: Dastaten@earthlink.net User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.4) Gecko/20030624 Netscape/7.1 (ax) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Rotary motors in aircraft Subject: Re: [FlyRotary] Re: Turbo Calculator References: In-Reply-To: Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit X-ELNK-Trace: 9a30bff84e6cb88f95c85d38d22416599ef193a6bfc3dd4831f7b890d7327216a402771ec8dbab7abd9aa8b00e01cd47350badd9bab72f9c350badd9bab72f9c X-Originating-IP: 24.238.206.157 I am following the turbo saga as well, and have been getting things in order to select the right turbo for our project as well. I am going to send mail off to Max (or call him tonight <his morning>) to determine some more parameters regarding the rebuilt turbo he sent John Slade. But, I will ask here as well in case someone has the info I am looking for.

I understand that Slade's rebuilt turbo has a compressor that is similar to a T04 V trim, but what I haven't been able to find is what the turbine side is equivalent to. Also, with regards to the turbine side, the information in general is quite scarce. I understand that you have T03 and T04 turbines out there, as well as T03 turbines mated to T04 compressors (Hybrids). My understanding is that the smaller (T03) turbines are lighter and spool faster, and when mated with a smaller compressor (also a T03 variety) that the pressures peak higher at lower RPM (good for off the line/acceleration).... whereas a hybrid (T03 turbine mated to a larger T04 compressor) develops the peak pressures at a higher RPM and generates more flow for a given pressure.

If that understanding is incorrect or in error, please point out what needs revising.

What I have yet to find is a good explanation of T03 Turbine "stages". The T03/hybrid turbo's listed for sale all have stage numbers (stage 1,2,3, etc) associated with them and I haven't quite figured out the difference (other than the overly simplistic/vague explanation that higher stages are for higher hp). Being a "why" kind of guy, I would like to be able to assimilate this properly.

Watching, Waiting, Ebaying..
Dave Staten

DaveLeonard wrote:

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