X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Wed, 18 Jan 2012 10:34:28 -0500 Message-ID: X-Original-Return-Path: Received: from nskntmtas02p.mx.bigpond.com ([61.9.168.140] verified) by logan.com (CommuniGate Pro SMTP 5.4.3) with ESMTP id 5354788 for lml@lancaironline.net; Wed, 18 Jan 2012 07:51:03 -0500 Received-SPF: pass receiver=logan.com; client-ip=61.9.168.140; envelope-from=frederickmoreno@bigpond.com Received: from nskntcmgw07p ([61.9.169.167]) by nskntmtas02p.mx.bigpond.com with ESMTP id <20120118125027.KLYQ3825.nskntmtas02p.mx.bigpond.com@nskntcmgw07p> for ; Wed, 18 Jan 2012 12:50:27 +0000 Received: from Razzle ([58.165.11.246]) by nskntcmgw07p with BigPond Outbound id P0qL1i0055JWv5W010qRKK; Wed, 18 Jan 2012 12:50:27 +0000 X-Authority-Analysis: v=2.0 cv=A+XuztqG c=1 sm=1 a=Ap2HPOVkqcVN/0SrKbfd8g==:17 a=JDadKst33uMA:10 a=8nJEP1OIZ-IA:10 a=Ia-xEzejAAAA:8 a=qyARXahu4UGh_X0r4FMA:9 a=Dtop7Pyu8MVfYOEZ6qIA:7 a=wPNLvfGTeEIA:10 a=EzXvWhQp4_cA:10 a=gTZD95DrypIKkOj8:21 a=g6tWHZICMIm4IMfZ:21 a=pGLkceISAAAA:8 a=r6UKCRJTlo2MIE2Z5YEA:9 a=xBrTuX7x5nAlSPAunXkA:7 a=MSl-tDqOz04A:10 a=38eTC5jwfoWE90v8:21 a=UfQ26_cglJ6NN9S0:21 a=Ap2HPOVkqcVN/0SrKbfd8g==:117 MIME-Version: 1.0 X-Original-Message-Id: <4F16BFFE.000166.01484@RAZZLE> X-Original-Date: Wed, 18 Jan 2012 20:50:06 +0800 Content-Type: Multipart/Alternative; charset="iso-8859-1"; boundary="------------Boundary-00=_INVZ5SXNTSM1VA400000" X-Mailer: IncrediMail (6244788) From: "Frederick Moreno" X-FID: FLAVOR00-NONE-0000-0000-000000000000 X-Priority: 3 X-Original-To: "Lancair Mail (lml@lancaironline.net)" Subject: Fw: HP --------------Boundary-00=_INVZ5SXNTSM1VA400000 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable I have a Performance Engines IO-550 that started out with 10:1 pistons un= til they rubbed the cylinders due to improper piston-bore clearance. It late= r failed in flight due to an ancient, out of tolerance rocker arm broke due= to high cycle fatigue. The crankcase and a lot of other stuff was found to = be out of tolerance during the teardown and inspection, and this stuff had t= o be replaced. So be careful with your engine. It could bite you. There a= re at least half a dozen Performance Engines units in Lancairs that went in = for premature teardown long before TBO and were found to have a lot of out of spec, non-conforming or old parts installed. I believe the FAA investigation continues. =0D =0D Be careful. =0D =0D Addressing your questions, dyno tests by Barrett Precision Engines with 1= 0:1 pistons yielded about 325 HP, almost 5% more power, and about what you would expect with the compression increase. What this means is that the conversion of avgas to power has a conversion constant of about 15.7 HP p= er gallon per hour operating at 50F lean of peak. =0D =0D So to make 65% of originally rated horsepower of 310 HP which is 201.5 HP= , divide by 15.7 and you get 12.8 gallons per hours which is where I used t= o fly. With the stock 8.5:1 pistons, the conversion constant is 15.0 HP pe= r gallon per hour, and it requires about 13.5 gallons per hour to run at 65= % which is where I run today. So the extra compression gives you a saving= s of almost one gallon per hour at the same power setting and speed, certai= nly worthwhile over a period of 2000 hours. =0D =0D To bad that Performance Engines screwed up on my engine. It cost me big time, and continues to do so.=0D =0D Sadder but Wiser Fred=0D =0D =0D =0D =0D -------Original Message-------=0D =0D From: Dan Ballin=0D Date: 18/01/2012 4:21:54 AM=0D To: lml@lancaironline.net=0D Subject: HP=0D =0D Anyone have thoughts about how to calculate horsepower on a 10:1=0D compression IO-550. Other than having it dyno'd, is there a way to=0D figure out how much HP I am generating. How would I figure out what=0D 75%, 80% etc is? I know fuel flow is a reasonable way to estimate HP=0D but what would I use as a conversion factor.=0D =0D I know this is pretty basic, but I am trying to set up my MVP 50 to=0D read out a realistic HP% number.=0D Yes it is a Performance Engine and no I don't believe their claim (an=0D stamp on the engine plate) of 370 HP.=0D =0D Thanks=0D =0D Dan Ballin=0D N386DM=0D =20 --------------Boundary-00=_INVZ5SXNTSM1VA400000 Content-Type: Text/HTML; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
I have a Performance Engines IO-550 that started out with 10:1 pisto= ns until they rubbed the cylinders due to improper piston-bore clearance.=   It later failed in flight due to an ancient, out of tolerance= rocker arm broke due to high cycle fatigue.  The crankcase and= a lot of other stuff was found to be out of tolerance during the teardow= n and inspection, and this stuff had to be replaced. So be careful with y= our engine.  It could bite you.  There are at least half a doze= n Performance Engines units in Lancairs that went in for premature teardo= wn long before TBO and were found to have a lot of out of spec, non-confo= rming or old parts installed.  I believe the FAA investigation conti= nues. 
 
Be careful.
 
Addressing your questions, dyno tests by Barrett Precision Engines w= ith 10:1 pistons yielded about 325 HP, almost 5%  more power, and ab= out what you would expect with the compression increase.  What this = means is that the conversion of avgas to power has a conversion constant = of about 15.7 HP per gallon per hour operating at 50F lean of peak. =
 
So to make 65% of originally rated horsepower of 310 HP which is 201= =2E5 HP, divide by 15.7 and you get 12.8 gallons per hours which is = where I used to fly.  With the stock 8.5:1 pistons, the convers= ion constant is 15.0 HP per gallon per hour, and it requires about 1= 3.5 gallons per hour to run at 65% which is where I run today.  So t= he  extra compression gives you a savings of almost one gallon = per hour at the same power setting and speed, certainly worthwh= ile over a period of 2000 hours. 
 
To bad that Performance Engines screwed up on my engine.  = It cost me big time, and continues to do so.
 
Sadder but Wiser Fred
 
 
 
 
-= ------Original Message-------
 
Date: 18/01/2012 4= :21:54 AM
Subject: HP
<= /DIV>
 
Anyone have thoughts about how to calculate horsepower on a 10:1
compression IO-550.  Other than having it dyno'd, is there= a way to
figure out how much HP I am generating.  How would I figur= e out what
75%, 80% etc is?  I know fuel flow is a reasonable way to = estimate HP
but what would I use as a conversion factor.
 
I know this is pretty basic, but I am trying to set up my MVP 50 to<= /DIV>
read out a realistic HP% number.
Yes it is a Performance Engine and no I don't believe their claim (a= n
stamp on the engine plate) of 370 HP.
 
Thanks
 
Dan Ballin
N386DM
 
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