X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from mail12.syd.optusnet.com.au ([211.29.132.193] verified) by logan.com (CommuniGate Pro SMTP 5.1.9) with ESMTPS id 2112267 for flyrotary@lancaironline.net; Tue, 19 Jun 2007 18:46:54 -0400 Received-SPF: none receiver=logan.com; client-ip=211.29.132.193; envelope-from=lendich@optusnet.com.au Received: from george (d58-105-75-130.dsl.nsw.optusnet.com.au [58.105.75.130]) by mail12.syd.optusnet.com.au (8.13.1/8.13.1) with SMTP id l5JMk9A9025140 for ; Wed, 20 Jun 2007 08:46:10 +1000 Message-ID: <007e01c7b2c3$a2c477a0$824b693a@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Different Rotary Port configurations Date: Wed, 20 Jun 2007 08:46:11 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_007B_01C7B317.73BDB260" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.2180 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.2180 X-Antivirus: avast! (VPS 0657-0, 12/12/2006), Outbound message X-Antivirus-Status: Clean This is a multi-part message in MIME format. ------=_NextPart_000_007B_01C7B317.73BDB260 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Monty, I wouldn't take the chance with a RX8 apex seal going over any sized = hole. Their not designed to do that as they are much smaller in height = and IMHO they will flex and spit out of the hole. Deeper 2mm slots have = been tried, with RX7 two piece but even with a wire cutter there is a = small ridge left, which might hang up an apex seal - so I'm going for a = 3mm apex seal. The slot depth is 9.8mm and is just as easily cut with a fly cutter as a = wire cutter. George ( down under) Jarrett, I'm working on a Pport Renesis. It works out being fairly mild port = timing. The key is that the side exhaust closes much sooner, therefore = the overlap is much less than even the old 6 port motor and the intake = closes WAY sooner than the new Renesis six port. Essentially I am moving = the intake down somewhat and creating a little bit of overlap. I don't = think that zero overlap is a good thing for anybody except CARB and the = EPA. The other nice thing is that the exhaust opens much later and more = gradually, so there is more expansion, and a lower EGT. Things that tend = to be kinder to the muffler etc. The port timing is somewhere between = the Mazda factory Pport and an old four port motor with the "lobe = center" retarded a bit to borrow from the piston world.=20 I'm not going for radical port size. Just 44mm. There is also the = question of how well the Renesis apex seals will do with a peripheral = port. At least it is an intake and not getting blasted with hot exhaust = gas, but there is still the question..... My reason for doing the Pport have more to do with my airframe, and = some other problems specific to my installation. I am not sure it is = worth the effort otherwise. As to BSFC....who knows. I hope to find out soon. Monty ------=_NextPart_000_007B_01C7B317.73BDB260 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Monty,
I wouldn't take the chance with a RX8 = apex seal=20 going over any sized hole. Their not designed to do that as they are=20 much smaller in height and IMHO they will flex and spit out of = the=20 hole. Deeper 2mm slots have been tried, with RX7 two piece but even = with a=20 wire cutter there is a small ridge left, which might hang up an apex = seal - so=20 I'm going for a 3mm apex seal.
The slot depth is 9.8mm and is just as = easily cut=20 with a fly cutter as a wire cutter.
George ( down under)
Jarrett,

I'm working on a Pport Renesis. It = works out being=20 fairly mild port timing. The key is that the side exhaust closes much = sooner,=20 therefore the overlap is much less than even the old 6 port motor and = the=20 intake closes WAY sooner than the new Renesis six port. Essentially I = am=20 moving the intake down somewhat and creating a little bit of overlap. = I don't=20 think that zero overlap is a good thing for anybody except CARB and = the EPA.=20 The other nice thing is that the exhaust opens much later and more = gradually,=20 so there is more expansion, and a lower EGT. Things that tend to be = kinder to=20 the muffler etc. The port timing is somewhere between the = Mazda=20 factory Pport and an old four port motor with the "lobe center" = retarded a bit=20 to borrow from the piston world.

I'm not going for radical port size. = Just 44mm.=20 There is also the question of how well the Renesis apex seals will do = with a=20 peripheral port. At least it is an intake and not getting blasted with = hot=20 exhaust gas, but there is still the question.....

My reason for doing the Pport have = more to do=20 with my airframe, and some other problems specific to my installation. = I am=20 not sure it is worth the effort otherwise.

As to BSFC....who knows. I hope to find = out=20 soon.

Monty


------=_NextPart_000_007B_01C7B317.73BDB260--