X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail-bw0-f222.google.com ([209.85.218.222] verified) by logan.com (CommuniGate Pro SMTP 5.3.2) with ESMTP id 4120810 for flyrotary@lancaironline.net; Thu, 11 Feb 2010 08:58:49 -0500 Received-SPF: pass receiver=logan.com; client-ip=209.85.218.222; envelope-from=msteitle@gmail.com Received: by bwz22 with SMTP id 22so993129bwz.5 for ; Thu, 11 Feb 2010 05:58:13 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:in-reply-to:references :date:message-id:subject:from:to:content-type; bh=lkCOkoZayiD+dYeRyMU3Ar43a0y2qhdczZfZ33kSe5o=; b=Y/SlZB5+z/tGiDgZ8DRRdmn8AemwPqOAO3yRRhRr2C2fLRboZSwrcc6SuHRDJQ2cSq JGPbz9EMRTMt68BjnY4/lqMfeBaYMzeRmcdH3R7O1DiBBkeEHN4IGB+lmshidHIAYRqr OKXnbWC2W7+iC/QkouViD16eEYZVKL+/YrFQs= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=u+2GJjzYzh+AtaOfdJWedhp8VwsqA/jVbHJsm09FA9kB47/Y/jSGML0SqMPhN0BOzA 6y8Pd5MHdIqPLkXpr/1VM5jzX6kqLQ4FHGjJsArmNQbYlJius8wMwHcsXWA+6EBY0YV8 hTKSGA0e3lvgk+JGj/G2IXF0hudwyKoVHd4tM= MIME-Version: 1.0 Received: by 10.204.29.21 with SMTP id o21mr1184713bkc.145.1265896693503; Thu, 11 Feb 2010 05:58:13 -0800 (PST) In-Reply-To: References: Date: Thu, 11 Feb 2010 07:58:11 -0600 Message-ID: <5cf132c1002110558g5adf9850je335682084230cbd@mail.gmail.com> Subject: Re: [FlyRotary] Oil cooling From: Mark Steitle To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary=00032555fdbebd1728047f538a63 --00032555fdbebd1728047f538a63 Content-Type: text/plain; charset=ISO-8859-1 On Thu, Feb 11, 2010 at 12:53 AM, Lynn Hanover wrote: > Lynn, I have no idea what a homogenizing muffler is. Explanation? > > > *The homoginizing muffler is a big can tight against the engine, with the > short tubes for headers. A large diameter tube through the end of the can > has hundreds of holes for the gasses to escape into the tube, then out of > the muffler and into the down pipe. Next to the engine it must be very > strong and made of Incolnel or Stainless to stay together. The header pipes > have no tuned length, and back pressure may cost HP. The can dumps lots of > heat under the cowl.* > ** > > Since I'm not modifying the port timing, changing to earlier rotors with > counter weights, I think the thing to do is to turbo it. > > *Early rotors would be lower compression than the Renesis rotors at 10:1. > So turbocharging would be less a problem. Use 3MM apex seals in ceramic. The > Renesis rotors have tapered side seals (I am told) Never seen one myself. > The apex seals and grooves are short as they never cross a port opening. > Both intake and exhaust ports are in the irons.* > > > I like your > idea of a huge compressor with no waste gate. A few pounds of boost > with a large volume. Seems Mazdatrix has abandoned the turbos for a > supercharger that does just that. 6 lbs of boost with the low end model > and 12 lbs for the bigger. Any idea who makes a turbo like that? Or a > supercharger that is small and will hold up to continuous use? > > *My thinking is that a poorly thought out turbo installation can produce > low boost * > *for several reasons.* > *One would be a compressor wheel too large. Another would be the turbine > wheel too small.* > ** > *Fine. So it only makes 3 pounds or 6 pounds close to sea level, and 1 or > 2 pounds at 8,000 feet. Perfect.* > *No muffler, or very little muffling required. No waste gate required. > Lycoming sea level HP at 8,000 feet where the Lycoming has only 117-145 HP. > By by Lycoming powered friends* > ** > *Superchargers can have very long lives. Big GM 2 cycle diesels have the > big 671 superchargers bolted tight to the blocks on millions of engines, > running for billions of hours around the world. * > > > Lynn, My water at 185 f and oil at 205 f was at WOT at 8000ft, prop at > 2450 and engine at 6980RPM. Yeah, the oil is high. I may be having the > situation that Tracy spoke of. Back pressure inside the cowl due to the > radiator having less restriction than the oil cooler. At high speed, > the cowl flaps don't help. Better than it was though. When I back off > on the throttle, it drops fast, although I don't remember how much. > > *That oil temp is costing you HP. With better cooling you might need more > prop. How nice. You can tell you are close on rejection rate when the temp > comes down with a bit less throttle. I use 3 40 row Setrab coolers and that > is not enough on a scalding hot day. The driver just short shifts to bring > the temps down. Like shifting at 9,200 RPM instead of 9,600 RPM. Then if you > are back under 180 you can do a lap shifting at 9,600 again with no problem. > * > ** > *If the oil temp goes over 200 and just stays there or only comes down > after a number of minutes at a lower throttle setting, then you are not > close, on rejection rate and must make a change. OIl temps above 160 are > costing HP. * > ** > *Lynn E. Hanover > * > Not that Lynn's comments need expounding on, but I had read in previous posts where Lynn stated that high oil temps cost HP and I shrugged it off thinking that high oil temps really couldn't make all *that* much of a difference. (Ignorance is bliss) Then I solved my oil cooling problem, bringing my oil temps down from 225-230 to 160-165, and I picked up 8-10 mph on the top end. WOW!!! That was the cheapest horsepower I ever got! So, I'm here to testify that Lynn's advice is well worth heeding if you want to go fast (don't we all?). Mark S. --00032555fdbebd1728047f538a63 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable

On Thu, Feb 11, 2010 at 12:53 AM, Lynn Hanover <= span dir=3D"ltr"><lehanover@gmail= .com> wrote:
Lynn,=A0 I have no idea what a homogenizing muffler is.=A0 Explanation= ?=A0
=A0
=A0
The homoginizing muffler is a big can tight against the eng= ine, with the short tubes for headers. A large diameter tube through the en= d of the can has hundreds of holes for the gasses to escape into the tube, = then out of the muffler and into the down pipe.=A0Next to the engine it mus= t be very strong and made of Incolnel or Stainless to stay together. The he= ader pipes have no tuned length, and back pressure may cost HP. The can dum= ps lots of heat under the cowl.
=A0
=A0
Since I'm not modifying the port timing, changing to earlie= r rotors with
counter weights, I think the thing to do is to turbo it.= =A0
=A0
Early rotors would be lower compression than the Renesis ro= tors at 10:1. So turbocharging would be less a problem. Use 3MM apex seals = in ceramic. The Renesis rotors have tapered side seals (I am told) Never se= en one myself. The apex seals and grooves are short as they never cross a p= ort opening. Both intake and exhaust ports are in the irons.
=A0
=A0
=A0I like your
idea of a huge compressor with no waste gate.=A0 A = few pounds of boost
with a large volume.=A0 Seems Mazdatrix has abandon= ed the turbos for a
supercharger that does just that.=A0 6 lbs of boost= with the low end model
and 12 lbs for the bigger.=A0 Any idea who makes a turbo like that? Or a supercharger that is small and will hold up to continuous use?
=A0
My thinking is that a poorly thought out turbo installation= can produce low boost=A0
for several reasons.
One would be a compressor wheel too large. Another would be= the turbine wheel too small.
=A0
Fine. So it only makes 3 pounds or 6 pounds close to sea le= vel, and 1 or 2 pounds at 8,000 feet. Perfect.
No muffler, or very little muffling required. No waste gate= required. Lycoming sea level HP at 8,000 feet where the Lycoming has only = 117-145 HP. By by Lycoming powered friends
=A0
Superchargers can have very long lives. Big GM 2 cycle dies= els have the big 671 superchargers bolted tight to the blocks on millions o= f engines, running for billions of hours around the world.=A0<= /div>
=A0

Lynn,=A0 My water at 185 f and oil at 205 f was at WOT at 8000ft, = prop at
2450 and engine at 6980RPM.=A0 Yeah, the oil is high.=A0 I may = be having the
situation that Tracy spoke of.=A0 Back pressure inside th= e cowl due to the
radiator having less restriction than the oil cooler.=A0 At high speed, the cowl flaps don't help.=A0 Better than it was though.=A0 When I bac= k off
on the throttle, it drops fast, although I don't remember how= much.
=A0
That oil temp is costing you HP. With better cooling you mi= ght need more prop. How nice. You can tell you are close on rejection rate = when the temp comes down with a bit less throttle. I use=A03 40 row Setrab = coolers and that is not enough on a scalding hot day. The driver just short= shifts to bring the temps down. Like shifting at 9,200 RPM instead of 9,60= 0 RPM. Then if you are back under 180 you can do a lap shifting at 9,600 ag= ain with no problem.
=A0
If the oil temp goes over 200 and just stays there or only = comes down after a number of minutes at a lower throttle setting, then you = are not close, on rejection rate and must make a change. OIl temps above 16= 0 are costing HP.
=A0
Lynn E. Hanover

Not that Lynn's comments need expounding on, but I had read in= previous posts where Lynn stated that high oil temps cost=A0HP and I shrug= ged it off=A0thinking that high oil temps really couldn't make all t= hat much of a difference.=A0 (Ignorance is bliss)=A0 Then I solved my o= il cooling problem, bringing my oil temps down from 225-230 to 160-165,=A0a= nd I picked up 8-10 mph on the top end.=A0 WOW!!!=A0That was the cheapest h= orsepower I ever got!=A0=A0So, I'm here to testify that Lynn's advi= ce is well worth heeding if you want to go fast (don't we all?).=A0=A0<= /div>
=A0
Mark S.=A0
--00032555fdbebd1728047f538a63--