X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from poplet2.per.eftel.com ([203.24.100.45] verified) by logan.com (CommuniGate Pro SMTP 5.3.5) with ESMTP id 4225778 for flyrotary@lancaironline.net; Sun, 18 Apr 2010 17:31:37 -0400 Received-SPF: none receiver=logan.com; client-ip=203.24.100.45; envelope-from=lendich@aanet.com.au Received: from sv1-1.aanet.com.au (mail.aanet.com.au [203.24.100.34]) by poplet2.per.eftel.com (Postfix) with ESMTP id C21291738C8 for ; Mon, 19 Apr 2010 05:31:00 +0800 (WST) Received: from ownerf1fc517b8 (203.171.92.134.static.rev.aanet.com.au [203.171.92.134]) by sv1-1.aanet.com.au (Postfix) with SMTP id 81E2FBEC038 for ; Mon, 19 Apr 2010 05:30:58 +0800 (WST) Message-ID: <814572650FB54D929E05777EDA57A583@ownerf1fc517b8> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Re: cooling for ground runs Date: Mon, 19 Apr 2010 07:31:01 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_0013_01CADF92.43001AA0" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5843 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 X-Antivirus: avast! (VPS 100418-1, 04/18/2010), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_0013_01CADF92.43001AA0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Mike, I have been a PP convert from the beginning, because of the additional = power gains, however my concerns from the beginning were fitting of the = PP, inlet size and shape and tuning for ram effect. I agree with Lynn on the inlet shape, however oblong is difficult to = achieve for everyone, so the round being next best and is easier to make = and fit, I settled on that. However I still had a nagging feeling that all PP's leak over time no = matter what you do to seal them. This belief as a result of many = discussions with engine rebuilders and racers. Now that Bill has designed the two piece inlet ( redesign of the = Powersport unit) with O ring sealing, I am much happier and will go that = way. I have already placed my order for some. Bill is intending to test the PP size for power as soon as humanly = possible, however it's not the highest priority, at this point in time. The Powersport were a lower reduction unit designed for max power at = 6,000 rpm. I can only assume ( from discussions) their considering = redesigning with a 2.8:1 ratio to take advantage of higher RPM, which = affects a whole range of things - including the PP size ( that certainly = is my suggestion anyway). My guess is a whole lot of work must be done = before they get to that stage.=20 All I can say is wait for the results, I believe you will be pleasantly = pleased with the additional power, my guess is about 230 hp for a 2 = rotor at 7,200 rpm - maybe more at that RPM and to 7,500 rpm. George (down under) Dave, I am going to do something different with the intake at some point. I = cant get the prop RPM that I should be getting in level flight and I = refuse to hack on the prop until I convince myself that there isnt a = little more HP in the engine via a better intake. Also, my current = config wont allow the fit of an air filter and I don=92t want to fly = forever without one. So would like to change the config to accommodate a = filter and ram air. I havent decided what route to take yet. Either a better 4 port = manifold or a PP engine/manifold. Waiting to see how the PP guys make = out (Mark S., how about an update). In either case I'll build it on my = spare engine and get it all done off the airplane so it is plug and play = with minimal down time. I hope to do it sometime next winter. Current status. Havent had a chance to fly again since my loss of = power due to fuel starvation a few weeks ago. Went through the entire = fuel system but didn=92t find a smoking gun. Replaced my fuel filters = with some higher flow units, but don=92t believe that was the problem. = Replaced my injectors with the original ones I had rebuilt by RC = Engineering. The new injectors flow more fuel so now the tuning is a = little out of whack. Also at the last oil change I switched from a straight weight mineral = oil to Mobil One. Now my previously tight engine leaks like a sieve. So = trying to address numerous oil leaks. But I think I'm getting close to = resuming flight. Oh, one more distraction. Just about into the soaring season so I'm = thrashing trying to get my glider ready for summer. Mike Wills =20 From: David Leonard=20 Sent: Saturday, April 17, 2010 11:05 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: cooling for ground runs Mike, Repeat after me: "I will not rebuild unnecessarily, I will fly = instead." "I will not rebuild unnecessarily, I will fly instead." "I = will not rebuild unnecessarily, I will fly instead." "I will not rebuild = unnecessarily, I will fly instead."=20 Lets face it. You tinkered with that thing for many years. If you = were ever going to get it right you would have done it by now. So quit = trying and keep flying. :-) David Leonard Turbo Rotary RV-6 N4VY http://N4VY.RotaryRoster.net http://RotaryRoster.net On Sat, Apr 17, 2010 at 10:51 PM, Mike Wills wrote: Scott, I agree with Dave, that looks great. One picture shows your intake = manifold. Looks like you used a casting for the lower part with a = transition to tubing. Where did you get the casting? Is it a stock Mazda = turbo casting that you cut the top off of? I'd like to do something = similar. Not real happy with my current manifold and would like to = rebuild it. Mike Wills From: David Leonard=20 Sent: Saturday, April 17, 2010 9:49 PM To: Rotary motors in aircraft=20 Subject: [FlyRotary] Re: cooling for ground runs Thanks Scott, You are right about what I said and I will clarify a little. I say = if it wont cool on the ground, it wont cool in the air because when I = first started flying I had marginal cooling on the ground and marginal = cooling in the air. At that time I could idle and taxi indefinitely = unless the OAT was above 85 or so, when my taxi times would be limited = to about 30 minutes. cooling in the air was similarly limited to = shallow climbs and less than full power in all but the coolest of = climates. However, Chris may be talking about high power ground runs which is = a different story. A full 5 minutes at full power on the ground is sure = to push the limits of most installations, and a temporary spray bar fed = from a hose is a reasonable thought if you feel the need to do extended = ground runs at or near full power. BTW Scott,=20 I just took another look at your website and picture. You sure have = done very nice workmanship. I can't wait to see that thing fly! It is = guaranteed to be one of the fastest RV's around. --=20 David Leonard Turbo Rotary RV-6 N4VY http://N4VY.RotaryRoster.net http://RotaryRoster.net On Sat, Apr 17, 2010 at 8:55 PM, wrote: Chris & Terria: I had ground running temp issues at lower power. Dave Leonard told = me that it's important to get it to self cool at low to mid power on the = ground. He said that reliance on sufficient cooling when you come up to = flying speed most likely won't work if it won't self cool on the ground. = I took his advise and redesigned my cooling system, which by the way = looks a lot like yours with major differences being cooler ducting and = cooler orientation. He's a link to my page @ EAA326 site: = http://gallery.eaa326.org/main.php?g2_itemId=3D1727 Tracy has commented that I should have reduced the cross section = of my oil cooler duct more quickly to force the air to uniformly pass = thru the oil cooler core. I applied that thinking to my water cooler = which I built next, and it worked even better than my cardboard and tape = trial duct. What is the engine RPM and % load that you start to have cooling = problems? Scott -----Original Message----- From: Chris and Terria To: Rotary motors in aircraft Sent: Sat, Apr 17, 2010 10:02 am Subject: [FlyRotary] cooling for ground runs Gents, I am doing the higher power ground runs now, and am only able to = run for about 5 minutes before reaching 195* or so. I=92m looking for = ideas on how to extend the time for each ground run. I was thinking of = adding a spray bar like others have discussed. My thought was to drill = some holes in some PVC and connect it to the garden hose. Then put it = in the intake in front of the radiator. I would have to run the hose = out the front and clamp it down so it doesn=92t come close to the prop. I=92m open to all ideas though. I=92ve attached a picture that shows my radiator and duct work. Thanks, Chris -- Homepage: http://www.flyrotary.com/ Archive and UnSub: = http://mail.lancaironline.net:81/lists/flyrotary/List.html --=20 ------=_NextPart_000_0013_01CADF92.43001AA0 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable
Mike,
I have been a PP convert from the = beginning,=20 because of the additional power gains, however my concerns from the = beginning=20 were fitting of the PP, inlet size and shape and tuning for ram=20 effect.
I agree with Lynn on the inlet shape, = however=20 oblong is difficult to achieve for everyone, so the round being next = best and is=20 easier to make and fit, I settled on that.
 
However I still had a nagging feeling = that all PP's=20 leak over time no matter what you do to seal them. = This belief  as a=20 result of many discussions with engine rebuilders and = racers.
 
Now that Bill has designed the two = piece inlet ( redesign of the = Powersport=20 unit) with O ring sealing, I am much happier and will go that way. I = have=20 already placed my order for some.
 
Bill is intending to test the PP size = for power as=20 soon as humanly possible, however it's not the highest priority, at this = point=20 in time.
 
The Powersport were a lower reduction=20 unit designed for max power at 6,000 rpm. I can only assume ( from=20 discussions) their considering redesigning with a 2.8:1 ratio to = take=20 advantage of higher RPM, which affects a whole range of things - = including the=20 PP size ( that certainly is my suggestion anyway). My guess is a = whole lot=20 of work must be done before they get to that stage. 
 
All I can say is wait for the results, = I believe=20 you will be pleasantly pleased with the additional power, my guess is = about 230=20 hp for a 2 rotor at 7,200 rpm - maybe more at that RPM and to 7,500=20 rpm.
George  (down under)
Dave,
 
I am going to do something different with = the intake=20 at some point. I cant get the prop RPM that I should be getting = in level=20 flight and I refuse to hack on the prop until I convince myself that = there=20 isnt a little more HP in the engine via a better intake. Also, my = current=20 config wont allow the fit of an air filter and I don=92t want = to fly=20 forever without one. So would like to change the config to accommodate = a=20 filter and ram air.
 
I havent decided what route to take yet. = Either a=20 better 4 port manifold or a PP engine/manifold. Waiting to see how the = PP guys=20 make out (Mark S., how about an update). In either case I'll = build it on=20 my spare engine and get it all done off the airplane so it is plug and = play=20 with minimal down time. I hope to do it sometime next=20 winter.
 
Current status. Havent had a chance to fly = again since=20 my loss of power due to fuel starvation a few weeks ago. Went through = the=20 entire fuel system but didn=92t find a smoking gun. Replaced my fuel = filters=20 with some higher flow units, but don=92t believe that was the problem. = Replaced=20 my injectors with the original ones I had rebuilt by RC Engineering. = The new=20 injectors flow more fuel so now the tuning is  a little out of=20 whack.
 
Also at the last oil change I switched from = a straight=20 weight mineral oil to Mobil One. Now my previously tight engine leaks = like a=20 sieve. So trying to address numerous oil leaks. But I think I'm = getting close=20 to resuming flight.
 
Oh, one more distraction. Just about into = the soaring=20 season so I'm thrashing trying to get my glider ready for = summer.
 
Mike Wills  

Sent: Saturday, April 17, 2010 11:05 PM
Subject: [FlyRotary] Re: cooling for ground = runs

Mike,
Repeat after me:  "I will not rebuild unnecessarily, I will = fly=20 instead." "I will not rebuild unnecessarily, I will fly instead." "I = will not=20 rebuild unnecessarily, I will fly instead." "I will not rebuild = unnecessarily,=20 I will fly instead."
 
Lets face it.  You tinkered with that thing for many = years.  If=20 you were ever going to get it right you would have done it by = now.  So=20 quit trying and keep flying.  :-)
David Leonard

Turbo Rotary RV-6 N4VY
http://N4VY.RotaryRoster.nethttp://RotaryRoster.net

On Sat, Apr 17, 2010 at 10:51 PM, Mike Wills = <rv-4mike@cox.net>=20 wrote:
Scott,
 
I agree with Dave, that looks great. One = picture=20 shows your intake manifold. Looks like you used a casting for the = lower part=20 with a transition to tubing. Where did you get the casting? Is it a = stock=20 Mazda turbo casting that you cut the top off of? I'd like to do = something similar. Not real happy with my current manifold and would = like to=20 rebuild it.
 
Mike Wills

Sent: Saturday, April 17, 2010 9:49 PM
Subject: [FlyRotary] Re: cooling for ground=20 runs

Thanks Scott,
You are right about what I said and = I will=20 clarify a little.  I say if it wont cool on the ground, it wont = cool in=20 the air because when I first started flying I had marginal cooling = on the=20 ground and marginal cooling in the air.  At that time I could = idle and=20 taxi indefinitely unless the OAT was above 85 or so, when my taxi = times=20 would be limited to about 30 minutes.  cooling in the air was = similarly=20 limited to shallow climbs and less than full power in all but the = coolest of=20 climates.

However, Chris may be talking about high power = ground runs=20 which is a different story.  A full 5 minutes at full power on = the=20 ground is sure to push the limits of most installations, and a = temporary=20 spray bar fed from a hose is a reasonable thought if you feel the = need to do=20 extended ground runs at or near full power.

BTW Scott,
I = just=20 took another look at your website and picture.  You sure have = done very=20 nice workmanship.  I can't wait to see that thing fly!  It = is=20 guaranteed to be one of the fastest RV's around.

--
David = Leonard

Turbo Rotary RV-6 N4VY
http://N4VY.RotaryRoster.net
http://RotaryRoster.net

On Sat, Apr 17, 2010 at 8:55 PM, <shipchief@aol.com> wrote:
Chris & Terria:
I had ground running temp issues at lower power. Dave Leonard = told me=20 that it's important to get it to self cool at low to mid power on = the=20 ground. He said that reliance on sufficient cooling when you come = up to=20 flying speed most likely won't work if it won't self cool on = the=20 ground. I took his advise and redesigned my cooling system, which = by the=20 way looks a lot like yours with major differences being cooler = ducting and=20 cooler orientation. He's a link to my page @ EAA326 site: http://gallery.eaa326.org/main.php?g2_itemId=3D1727Tracy=20 has commented that I should have reduced the cross section of my = oil=20 cooler duct more quickly to force the air to uniformly pass thru = the oil=20 cooler core. I applied that thinking to my water cooler which I = built=20 next, and it worked even better than my cardboard and tape trial=20 duct.
What is the engine RPM and % load that you start to have = cooling=20 problems?
Scott


-----Original Message-----
From: Chris and Terria <candtmallory@embarqmail.com>
To: Rotary = motors in=20 aircraft <flyrotary@lancaironline.net>
Sent: Sat, = Apr 17,=20 2010 10:02 am
Subject: [FlyRotary] cooling for ground = runs

Gents,
 
I am doing the higher power ground runs = now, and am=20 only able to run for about 5 minutes before reaching 195* or = so.  I=92m=20 looking for ideas on how to extend the time for each ground = run.  I=20 was thinking of adding a spray bar like others have = discussed.  My=20 thought was to drill some holes in some PVC and connect it to the = garden=20 hose.  Then put it in the intake in front of the = radiator.  I=20 would have to run the hose out the front and clamp it down so it = doesn=92t=20 come close to the prop.
 
I=92m open to all ideas though.
 
I=92ve attached a picture that shows my = radiator and=20 duct work.
 
Thanks,
 
Chris
--
Homepage:  http://www.flyrotary.com/
Archive and UnSub:   http://mail.lancaironline.net:81/lists/flyrotary/List.htm=
l






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