Return-Path: Received: from relay02.roc.ny.frontiernet.net ([66.133.131.35] verified) by logan.com (CommuniGate Pro SMTP 4.1.4) with ESMTP id 2607416 for flyrotary@lancaironline.net; Sun, 28 Sep 2003 22:12:12 -0400 Received: (qmail 14347 invoked from network); 29 Sep 2003 02:12:10 -0000 Received: from unknown (HELO frontiernet.net) ([170.215.97.8]) (envelope-sender ) by relay02.roc.ny.frontiernet.net (FrontierMTA 2.3.6) with SMTP for ; 29 Sep 2003 02:12:10 -0000 Message-ID: <3F778795.65B746B6@frontiernet.net> Date: Sun, 28 Sep 2003 21:15:02 -0400 From: Jim Sower X-Mailer: Mozilla 4.77 [en] (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Rotary motors in aircraft Subject: Re: [FlyRotary] Life is better at 5 psi References: Content-Type: multipart/alternative; boundary="------------6989D543763ADEFD16741BA3" --------------6989D543763ADEFD16741BA3 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Rusty, Glad you're back on track. I spent part of the afternoon with Turbo Tom at a soaring club (he was the tractor driver this weekend, and I'm going to get into this stuff). We discussed turbos as some length. He predicted that you'd be happier with 5-10 psi than with the 5" you started with. He doesn't regard Mazda as an ideal turbo platform. The exhaust is hotter, so the turbo is hotter so the intake charge is hotter so you need even more intercooler than other folks. Also, since rotarys aren't exactly torque factories, the benefits are not as great as with recips. That said, he assured me that it CAN be done - but you will need a SERIOUS intercooler for good results. No surprises here. Rotarys are famous for heat rejection problems, and this is one more. The secret is to be VERY careful around optimizing the plenum so as to maximize flow through the heat exchanger while minimizing cooling drag. Today's rendition of the gospel according to TT .... Jim S. Russell Duffy wrote: > Greetings,I took the plane out again today, and found it to > be MUCH more satisfying at 5 psi of boost. I ordered another > excellent used 89-91 turbo off Ebay today, and I'm going to > pick up a crack free exhaust manifold to go with it. Before I > install the new turbo, I'll port the crap out of the > wastegate, to see if I can get down to something more > reasonable, like 5 psi, rather than 10+ like I get now. If > that works, I can actually use full throttle, which will make > me, and Lynn happy (see Lynn, I do pay attention). I'm also > trying to pick up an 87-88 turbo actuator, which was only 5.5 > psi I think. As I mentioned before, the new cowl is on order, > and I'm starting to work out the details to get this all > inside the stock cowl. I can't imagine how nice it might fly > without all the cowl and tire drag. Realistically, it will > probably be around the first of the year before this all > happens, but at least I'm back on track, and excited about > doing it all. Thanks for putting up with my earlier > depression. This IS going to work, and it IS going to be the > hotrod I hoped for. Cheers,Rusty (psyched again) > > "urn:schemas-microsoft-com:office:smarttags" />9-27-03.7 > hrs/2.7 total > > "urn:schemas-microsoft-com:office:office" /> > > Started my climb out at 4 psi of boost, then modified to 5 psi > around a thousand feet or so.I couldn’t get any rational VSI > readings from the Anywhere map, but it sure did climb better > than ever.The oil and water both stayed right at 180 degrees, > so no problems there.I had the usual ceiling of about 2500 ft, > so I couldn’t go higher for any real testing.Here are the > numbers for 14 degrees of pitch: > > Boost (over ambient) / MAP / RPM / MPH > > Climb > > 4 psi / 38” / 5600 / 100 > > 5 psi / 40” / 5800 / 100 > > Cruise at 2000 ft > > 0 psi / 28” / 5600 / 130 > > 3 psi / 34” / 6000 / 145 > > 5 psi / 38” / 6300 / 155 > > Once I returned (with another beautiful landing I might add), > I planned to fill the tanks, and increase the pitch of the > prop to 16 degrees. > > Unfortunately, I found that my left brake line is leaking > again.The line was made of slightly softer aluminum than Van > may have had in mind, but I can’t figure out what was actually > in the RV-8, and he doesn’t spec the material for the RV-3 > either, so I thought I’d give it a try.I left a loop of brake > line at the caliper, and I believe that vibration is causing > this to break at the flare.After one of the early leaks, the > brake on the left has been “chattering”, rather than smoothly > braking, so I figured it must have been soaked with fluid.To > make sure this never happens again, I will replace the pads > (which are 22 years old) on both brakes, and replace the lines > with stronger aluminum.I will also get rid of the loop of > line, since it could be part of the problem.It’ll be nice > weather tomorrow, but I won’t be flying. > > I found one other problem today, my air vent sucks, and I mean > literally.Rather than blowing air on me like it’s supposed to, > it has a pretty large suction on it.One way or another, air is > coming in, so I guess it’s still ventilation. > -- Jim Sower Crossville, TN; Chapter 5 Long-EZ N83RT, Velocity N4095T --------------6989D543763ADEFD16741BA3 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: 8bit Rusty,
Glad you're back on track.  I spent part of the afternoon with Turbo Tom at a soaring club (he was the tractor driver this weekend, and I'm going to get into this stuff).  We discussed turbos as some length.  He predicted that you'd be happier with 5-10 psi than with the 5" you started with.  He doesn't regard Mazda as an ideal turbo platform.  The exhaust is hotter, so the turbo is hotter so the intake charge is hotter so you need even more intercooler than other folks.  Also, since rotarys aren't exactly torque factories, the benefits are not as great as with recips.  That said, he assured me that it CAN be done - but you will need a SERIOUS intercooler for good results.  No surprises here.  Rotarys are famous for heat rejection problems, and this is one more.  The secret is to be VERY careful around optimizing the plenum so as to maximize flow through the heat exchanger while minimizing cooling drag.

Today's rendition of the gospel according to TT .... Jim S.

Russell Duffy wrote:

 Greetings,I took the plane out again today, and found it to be MUCH more satisfying at 5 psi of boost.  I ordered another excellent used 89-91 turbo off Ebay today, and I'm going to pick up a crack free exhaust manifold to go with it.  Before I install the new turbo, I'll port the crap out of the wastegate, to see if I can get down to something more reasonable, like 5 psi, rather than 10+ like I get now.  If that works, I can actually use full throttle, which will make me, and Lynn happy (see Lynn, I do pay attention).   I'm also trying to pick up an 87-88 turbo actuator, which was only 5.5 psi I think. As I mentioned before, the new cowl is on order, and I'm starting to work out the details to get this all inside the stock cowl.  I can't imagine how nice it might fly without all the cowl and tire drag.  Realistically, it will probably be around the first of the year before this all happens, but at least I'm back on track, and excited about doing it all.   Thanks for putting up with my earlier depression.  This IS going to work, and it IS going to be the hotrod I hoped for. Cheers,Rusty (psyched again)

<?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-com:office:smarttags" />9-27-03.7 hrs/2.7 total

<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

Started my climb out at 4 psi of boost, then modified to 5 psi around a thousand feet or so.I couldn’t get any rational VSI readings from the Anywhere map, but it sure did climb better than ever.The oil and water both stayed right at 180 degrees, so no problems there.I had the usual ceiling of about 2500 ft, so I couldn’t go higher for any real testing.Here are the numbers for 14 degrees of pitch:

Boost (over ambient) / MAP / RPM / MPH

Climb

4 psi / 38” / 5600 / 100

5 psi / 40” / 5800 / 100

Cruise at 2000 ft

0 psi / 28” / 5600 / 130

3 psi / 34” / 6000 / 145

5 psi / 38” / 6300 / 155

Once I returned (with another beautiful landing I might add), I planned to fill the tanks, and increase the pitch of the prop to 16 degrees.

Unfortunately, I found that my left brake line is leaking again.The line was made of slightly softer aluminum than Van may have had in mind, but I can’t figure out what was actually in the RV-8, and he doesn’t spec the material for the RV-3 either, so I thought I’d give it a try.I left a loop of brake line at the caliper, and I believe that vibration is causing this to break at the flare.After one of the early leaks, the brake on the left has been “chattering”, rather than smoothly braking, so I figured it must have been soaked with fluid.To make sure this never happens again, I will replace the pads (which are 22 years old) on both brakes, and replace the lines with stronger aluminum.I will also get rid of the loop of line, since it could be part of the problem.It’ll be nice weather tomorrow, but I won’t be flying.

I found one other problem today, my air vent sucks, and I mean literally.Rather than blowing air on me like it’s supposed to, it has a pretty large suction on it.One way or another, air is coming in, so I guess it’s still ventilation.

--
Jim Sower
Crossville, TN; Chapter 5
Long-EZ N83RT, Velocity N4095T
  --------------6989D543763ADEFD16741BA3--