X-Virus-Scanned: clean according to Sophos on Logan.com X-PolluStop-Diagnostic: (direct reply)\eX-PolluStop-Score: 0.00\eX-PolluStop: Scanned with Niversoft PolluStop 2.1 RC1, http://www.niversoft.com/pollustop Return-Path: Received: from mail07.syd.optusnet.com.au ([211.29.132.188] verified) by logan.com (CommuniGate Pro SMTP 4.3c4) with ESMTPS id 867245 for flyrotary@lancaironline.net; Wed, 13 Apr 2005 02:35:21 -0400 Received-SPF: none receiver=logan.com; client-ip=211.29.132.188; envelope-from=lendich@optusnet.com.au Received: from george (d211-31-219-235.dsl.nsw.optusnet.com.au [211.31.219.235]) by mail07.syd.optusnet.com.au (8.12.11/8.12.11) with SMTP id j3D6YTve010280 for ; Wed, 13 Apr 2005 16:34:31 +1000 Message-ID: <001d01c53ff3$5c377bb0$ebdb1fd3@george> From: "George Lendich" To: "Rotary motors in aircraft" References: Subject: Re: [FlyRotary] Rx-8 Rotors in Rx-7 Block Date: Wed, 13 Apr 2005 16:38:09 +1000 MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="----=_NextPart_000_001A_01C54047.2D67CC00" X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2800.1106 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 This is a multi-part message in MIME format. ------=_NextPart_000_001A_01C54047.2D67CC00 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable It would seem to me that they are saying they run the rotors backwards - = that would put the recess in the rotor face backwards. The deeper side is to the side of rotation I'm sure that would cause = some power loss - then again I'm not the expert! The ceramic apex seals are the seals of choice, I didn't know they were = that expensive! George (down under) Appended below is an e mail from the owner of MazdaTrix about using = the Rx-8 rotor in an RX-7 block. Interesting reading, now if only the = ceramic seals were not $3600 for a set for two rotors I'd be ready {:>). = Makes for interesting reading. Ed Anderson Rv-6A N494BW Rotary Powered Matthews, NC eanderson@carolina.rr.com Here is an e-mail that Dave Lemon from Mazdatrix sent an RX-7 forum = member on the subject. Just thought you guys would find it interesting: We are using RX-8 rotors in one of our SCCA E/Production "street port" = 86-91 13B non-turbo engines. We do no mods to the rotors (except installing the racing rotor = bearing). We are using RX-8 racing ceramic apex seals (the OEM RX-8 steel seals = warped too much having to cross the exhaust port). (There IS enough metal to cut the apex seal groove for either 86-91 = 2mm seals or earlier 3mm seals -- we are looking into making that = service available, but are not ready yet) The rotors are run "backwards" (front in rear, rear in front) so the = angle cut on the side of the rotor gives more intake opening timing = (RX-8 uses the cuts for the side exhaust ports). Do not use the "oil scraper ring" outside the second oil control ring. DO NOT use RX-8 corner seals -- they DESTROY 86-91 side housings !!!! = (use 86-91 corner seals, TRUST ME). They ARE lighter than 89-91 non-turbo rotors, have higher compression, = and are less expensive. With all of the above said: We have YET to attain even the SAME = horsepower on the dyno as we are getting from our race engine(s) using = the 89-91 non-turbo rotors !!! Potentials: With the RX-8 rotor having the side seal further outboard, we were = able to increase the (ported) intake opening timing versus the earlier = rotors -- it may be too much ??? (does not seem likely) Running the rotors with the angle cut for intake opening may also be = in the above category. We always set pre-92 side seal clearance at about .0015 (1 1/2 thou). = The SMALLEST clearance we could get, using the LONGEST of the available = "pre-sized" RX-8 side seals was about .010 (10 thou), with the worst on = this set of rotors of about .016 (16 thou). This gives a much lower = "sealing" than we like. Other than the above, at this time we are not at all sure why the = power is less than when using the earlier rotors. No, we have not done the REAL test -- run the SAME engine on the dyno, = and only swap the rotors (backwards, then normal). That equals three = builds, and three full dyno on-and-offs + dyno sessions.=20 Dave Lemon,=20 Owner of Mazdatrix,=20 The dyno operator and driver of the E/P car ------=_NextPart_000_001A_01C54047.2D67CC00 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
It would seem to me that they are = saying they run=20 the rotors backwards - that would put the recess in the rotor face=20 backwards.
 
The deeper side is to the side of = rotation I'm sure=20 that would cause some power loss - then again I'm not the = expert!
 
The ceramic apex seals are the seals of = choice, I=20 didn't know they were that expensive!
 
George (down under)
Appended below is an e mail from the = owner of=20 MazdaTrix about using the Rx-8 rotor in an RX-7 block.  = Interesting=20 reading, now if only the ceramic seals were not $3600 for a set for = two rotors=20 I'd be ready {:>).  Makes for interesting = reading.
 
 
Ed Anderson
Rv-6A N494BW Rotary=20 Powered
Matthews, NC
eanderson@carolina.rr.com
 
Here is an e-mail that Dave Lemon from Mazdatrix sent an RX-7 = forum=20 member on the subject. Just thought you guys would find it=20 interesting:



We are using RX-8 rotors in one of our = SCCA=20 E/Production "street port" 86-91 13B non-turbo engines.

We do = no mods=20 to the rotors (except installing the racing rotor bearing).
We are = using=20 RX-8 racing ceramic apex seals (the OEM RX-8 steel seals warped too = much=20 having to cross the exhaust port).
(There IS enough metal to cut = the apex=20 seal groove for either 86-91 2mm seals or earlier 3mm seals -- we are = looking=20 into making that service available, but are not ready yet)
The = rotors are=20 run "backwards" (front in rear, rear in front) so the angle cut on the = side of=20 the rotor gives more intake opening timing (RX-8 uses the cuts for the = side=20 exhaust ports).
Do not use the "oil scraper ring" outside the = second oil=20 control ring.
DO NOT use RX-8 corner seals -- they DESTROY 86-91 = side=20 housings !!!! (use 86-91 corner seals, TRUST ME).

They ARE lighter than 89-91 non-turbo rotors, = have=20 higher compression, and are less = expensive.

With all of=20 the above said: We have YET to attain even the SAME horsepower on the = dyno as=20 we are getting from our race engine(s) using the 89-91 non-turbo = rotors=20 !!!

Potentials:
With the RX-8 rotor having the side seal = further=20 outboard, we were able to increase the (ported) intake opening timing = versus=20 the earlier rotors -- it may be too much ??? (does not seem=20 likely)

Running the rotors with the angle cut for intake = opening may=20 also be in the above category.

We always set pre-92 side seal = clearance=20 at about .0015 (1 1/2 thou). The SMALLEST clearance we could get, = using the=20 LONGEST of the available "pre-sized" RX-8 side seals was about .010 = (10 thou),=20 with the worst on this set of rotors of about .016 (16 thou). This = gives a=20 much lower "sealing" than we like.

Other than the above, at = this time=20 we are not at all sure why the power is less than when using the = earlier=20 rotors.

No, we have not done the REAL test -- run the SAME = engine on=20 the dyno, and only swap the rotors (backwards, then normal). That = equals three=20 builds, and three full dyno on-and-offs + dyno sessions. =


Dave=20 Lemon,
Owner of Mazdatrix,
The dyno operator and driver of the = E/P=20 car
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