X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from omr-m01.mx.aol.com ([64.12.143.75] verified) by logan.com (CommuniGate Pro SMTP 6.0.5) with ESMTPS id 6364687 for flyrotary@lancaironline.net; Mon, 08 Jul 2013 11:23:51 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.143.75; envelope-from=shipchief@aol.com Received: from mtaout-mb06.r1000.mx.aol.com (mtaout-mb06.r1000.mx.aol.com [172.29.41.70]) by omr-m01.mx.aol.com (Outbound Mail Relay) with ESMTP id 62BCA7009D89C for ; Mon, 8 Jul 2013 11:23:16 -0400 (EDT) Received: from [10.226.116.188] (15.sub-174-239-196.myvzw.com [174.239.196.15]) (using TLSv1 with cipher AES128-SHA (128/128 bits)) (No client certificate requested) by mtaout-mb06.r1000.mx.aol.com (MUA/Third Party Client Interface) with ESMTPSA id 12AB3E0000DB for ; Mon, 8 Jul 2013 11:23:15 -0400 (EDT) Subject: Re: [FlyRotary] Re: Turbo boost indication References: From: Scott Emery Content-Type: multipart/alternative; boundary=Apple-Mail-2--147198295 X-Mailer: iPhone Mail (8E600) In-Reply-To: Message-Id: <468999E1-E928-4EE5-83F2-10031D10BF97@aol.com> Date: Mon, 8 Jul 2013 08:23:09 -0700 To: Rotary motors in aircraft Content-Transfer-Encoding: 7bit Mime-Version: 1.0 (iPhone Mail 8E600) x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20121107; t=1373296996; bh=abrlXPV9DBGcTERzgVtEGn0xXrA71wTme2UOmHkx5og=; h=From:To:Subject:Message-Id:Date:Mime-Version:Content-Type; b=YRrRJasEjvsJgO0GyL7u39jUxBlwGT9i+BgpSImxk0Y9lacmZjVw3eiowikT4QU69 ordUzsaiLeAemgvNCmef7m2f/FWs7CBfMvdQWzZVIjH4SBujE67kgb+CGOXg4vHVfm 8DzEvYtepJL6hETuFkjq2YQKxpSd1jEjozsjsGKI= X-AOL-SCOLL-SCORE: 0:2:427969216:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d294651dad962148f X-AOL-IP: 174.239.196.15 --Apple-Mail-2--147198295 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset=us-ascii Last night (from epay) I bought a manifold pressure gauge for a twin Cessna.= The two needles are labelled Front & Rear. It's marked 10 to 50 inches of m= ercury absolute. I intend to use it to read turbo boost before the throttle b= ody, and manifold pressure after the throttle body.=20 I'm having a hard time finding an intercooler that fits the available space p= lus has a usable configuration of inlet/outlet tubes. The stock rx7 intercoo= ler I have in hand seems the best so far, but it's a bit small compared to a= ftermarket offerings. Sent from my iPhone On Jul 7, 2013, at 2:17 PM, Scott Emery wrote: > I'm thinking my "Blown Engine" experience might be avoidable in the future= if I add a large manifold pressure gauge in plain sight, install a 1.30 A/R= exhaust housing, retard the timing, run 100 LL blue gas, and add an interco= oler.=20 > In that order. > I got an engine hoist yesterday so now I can put the repaired engine back o= n. Getting it off didn't require as much precision... > After I get some experience, I'll try different grades of mogas @ defined m= anifold pressure limits. >=20 > Sent from my iPhone >=20 > On Jul 6, 2013, at 12:36 PM, David Leonard wrote: >=20 >> OK, so the more accurate conversion is=20 >> 20psi=3D40.7 in Hg >> so in your example >> 20psi boost =3D 70.6 in MAP (Manifold Absolute Pressure) >>=20 >> It help in your article, turbos work as a boost ratio. So this turbo it t= hen making a boost ratio of: >> 70.6 / 29.9 =3D 2.36 >>=20 >> So as you go up in altitude you multiply the ambient pressure by 2.36 >>=20 >> So at 17,500 ft the pressure is half, and so is the MAP, or, 35.3 " MAP >>=20 >> Losses are not porportunately reduced, and the turbo may be less efficien= t in that range so actual MAP may be less. >>=20 >>=20 >>=20 >>=20 >> On Sat, Jul 6, 2013 at 11:57 AM, Patrick Panzera wrote: >> I'm editing an article about a bone stock, turbocharged direct injection c= ar engine that boasts 20 lbs of boost.=20 >>=20 >> I want to convert that to MP so us airplane junkies can wrap our heads ar= ound it. >>=20 >> Thanks! >>=20 >> Pat=20 >>=20 >>=20 >> On Sat, Jul 6, 2013 at 11:44 AM, David Leonard wrot= e: >> Simply convert 20 psi to Inches of Hg (its about 2 to 1 but not exactly) a= nd add it to 29.9. So the MP should be about 69 inches, give or take depend= ing on losses and where in the system you measure. >>=20 >> I keep my plane less that 45 inches MP. You have to be more rich and ski= lled than me to go higher without detonation. >>=20 >>=20 >> On Sat, Jul 6, 2013 at 11:14 AM, Patrick Panzera wrote: >> Friends, >>=20 >> Hypothetical question.=20 >> Let's say it's a standard day and I'm at sea level. >> I've installed a turbocharger and have also connected the stock automobil= e turbo boost gauge, along with my traditional manifold pressure gauge. >>=20 >> I ground-run the engine to full throttle (where the MP would normally be r= eading 29.92- minus some efficiency loss) and the boost gauge is reading 20 p= si. >>=20 >> What should the MP indicator be reading? >>=20 >> Thanks! >>=20 >> Pat >>=20 >>=20 >>=20 >>=20 >> --=20 >> David Leonard >>=20 >> Turbo Rotary RV-6 N4VY >> http://N4VY.RotaryRoster.net >> http://RotaryRoster.net >>=20 >>=20 >>=20 >>=20 >> --=20 >> David Leonard >>=20 >> Turbo Rotary RV-6 N4VY >> http://N4VY.RotaryRoster.net >> http://RotaryRoster.net --Apple-Mail-2--147198295 Content-Transfer-Encoding: quoted-printable Content-Type: text/html; charset=utf-8
Last night (from epay) I bought a manif= old pressure gauge for a twin Cessna. The two needles are labelled Front &am= p; Rear. It's marked 10 to 50 inches of mercury absolute. I intend to use it= to read turbo boost before the throttle body, and manifold pressure after t= he throttle body. 
I'm having a hard time finding an intercoo= ler that fits the available space plus has a usable configuration of inlet/o= utlet tubes. The stock rx7 intercooler I have in hand seems the best so far,= but it's a bit small compared to aftermarket offerings.

Sent from my= iPhone

On Jul 7, 2013, at 2:17 PM, Scott Emery <shipchief@aol.com> wrote:

I'm thinking my "Blown Engine" e= xperience might be avoidable in the future if I add a large manifold pressur= e gauge in plain sight, install a 1.30 A/R exhaust housing, retard the timin= g, run 100 LL blue gas, and add an intercooler. 
In that orde= r.
I got an engine hoist yesterday so now I can put the repaired e= ngine back on. Getting it off didn't require as much precision...
= After I get some experience, I'll try different grades of mogas @ defined ma= nifold pressure limits.

Sent from my iPhone

On Jul 6, 2= 013, at 12:36 PM, David Leonard <<= a href=3D"mailto:wdleonard@gmail.com">wdleonard@gmail.com> wrote:=

OK,= so the more accurate conversion is 
20psi=3D40.7 in Hg
s= o in your example
20psi boost =3D 70.6 in MAP (Manifold Absolute P= ressure)

It help in your article, turbos work as a b= oost ratio.  So this turbo it then making a boost ratio of:
70.6 / 29.9  =3D 2.36

So as you go up in a= ltitude you multiply the ambient pressure by 2.36

S= o at 17,500 ft the pressure is half, and so is the MAP, or, 35.3 " MAP
=

Losses are not porportunately reduced, and the turbo may= be less efficient in that range so actual MAP may be less.




On Sat, Jul 6, 2013 at 11:57 AM, Patrick Panzera <editor@contactmagazine.com> wrote:
I'm editing an article about a bone stock, turbocharged dir= ect injection car engine that boasts 20 lbs of boost.

I want to= convert that to MP so us airplane junkies can wrap our heads around it.

Thanks!

Pat 


On Sat, Jul 6, 2013 at 11:44 AM, David Leonard <wdleonard@gmail.com> wrote:
Simply convert 20 psi to Inch= es of Hg (its about 2 to 1 but not exactly) and add it to 29.9.  So the= MP should be about 69 inches, give or take depending on losses and where in= the system you measure.

I keep my plane less that 45 inches MP.  You have to be more= rich and skilled than me to go higher without detonation.


On Sat, Jul 6, 2013 a= t 11:14 AM, Patrick Panzera <editor@contactmaga= zine.com> wrote:
Friends,

Hypothe= tical question. 
Let's say it's a standard day and I'm at sea= level.
I've installed a turbocharger and have also connected the stock automob= ile turbo boost gauge, along with my traditional manifold pressure gauge.

I ground-run the engine to full throttle (where the MP w= ould normally be reading 29.92- minus some efficiency loss) and the boost ga= uge is reading 20 psi.

What should the MP indicator= be reading?

Thanks!

Pat




--
David Leonard

Turbo Rotary RV-6 N4VYhttp:= //N4VY.RotaryRoster.net
http://RotaryRoster.ne= t




--
D= avid Leonard

Turbo Rotary RV-6 N4VY
http://N4VY.RotaryRoster.net
http://RotaryRoster.net
= --Apple-Mail-2--147198295--