X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Received: from imr-ma02.mx.aol.com ([64.12.206.40] verified) by logan.com (CommuniGate Pro SMTP 5.3.8) with ESMTP id 4399353 for flyrotary@lancaironline.net; Tue, 20 Jul 2010 00:06:00 -0400 Received-SPF: pass receiver=logan.com; client-ip=64.12.206.40; envelope-from=Lehanover@aol.com Received: from imo-da03.mx.aol.com (imo-da03.mx.aol.com [205.188.169.201]) by imr-ma02.mx.aol.com (8.14.1/8.14.1) with ESMTP id o6K45K59009091 for ; Tue, 20 Jul 2010 00:05:20 -0400 Received: from Lehanover@aol.com by imo-da03.mx.aol.com (mail_out_v42.9.) id q.c27.83218910 (43970) for ; Tue, 20 Jul 2010 00:05:15 -0400 (EDT) Received: from magic-d20.mail.aol.com (magic-d20.mail.aol.com [172.19.155.136]) by cia-dd03.mx.aol.com (v129.4) with ESMTP id MAILCIADD033-abc24c45207b1b; Tue, 20 Jul 2010 00:05:15 -0400 From: Lehanover@aol.com Message-ID: <6dd5a.66059f07.39767a7b@aol.com> Date: Tue, 20 Jul 2010 00:05:15 EDT Subject: Fwd: Port timing basics by Paul Yaw To: flyrotary@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="part1_6dd5a.66059f07.39767a7b_boundary" X-Mailer: AOL 9.5 sub 185 X-AOL-ORIG-IP: 173.88.9.178 X-AOL-IP: 172.19.155.136 X-Spam-Flag:NO X-AOL-SENDER: Lehanover@aol.com --part1_6dd5a.66059f07.39767a7b_boundary Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable If you want to get into the weeds on how rotaries work, here is the port= =20 timing for many stock and racing engines. From Paul Yaw's web site. Now= =20 closed down. =20 Notice that the factory Periphery port timing is more modest than the "J"= =20 bridge port timing. So the Pport actually idles and slow runs smoother tha= n =20 the bridge ported engines. =20 =20 =20 ____________________________________ =20 =20 Port Timing IO =3D Intake opens IC =3D Intake closes EO =3D Exhaust opens EC =3D Exhaust closes =20 US Model First Generation RX-7 IO 32=B0 ATDC IC 40=B0 ABDC EO 75=B0 BBDC EC 38=B0 ATDC =20 European Model First Generation RX-7 IO 32=B0 ATDC IC 50=B0 ABDC EO 75=B0 BBDC EC 48=B0 ATDC =20 First and Second Generation 6-Port 13B Primary intake (Part throttle/cruise) IO 32=B0 ATDC IC 40=B0 ABDC Secondary intake (Part to full throttle) IO 32=B0 ATDC IC 30=B0 ABDC Auxiliary high speed ports (Full throttle above approximately 4000 rpm) IO 45=B0 ATDC IC 70=B0 ABDC EO 71=B0 BBDC EC 48=B0 ATDC =20 Second and Third Generation Turbo 13B IO 32=B0 ATDC IC 50=B0 ABDC EO 71=B0 BBDC EC 48=B0 ATDC =20 Racing Beat "Street Port" IO 25=B0 ATDC IC 60=B0 ABDC EO 84=B0 BBDC EC 48=B0 ATDC =20 Racing Beat "J-Bridge Port" IO 115=B0 BTDC IC 72=B0 ABDC EO 88=B0 BBDC EC 57=B0 ATDC =20 Mazda Factory Peripheral Port IO 86=B0 BTDC IC 75=B0 ABDC EO 73=B0 BBDC EC 65=B0 ATDC =20 --part1_6dd5a.66059f07.39767a7b_boundary Content-Type: text/html; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable <= FONT id=3Drole_document color=3D#000000 size=3D2 face=3DArial>

If you want to get into the weeds on how rotaries work, here is= the=20 port timing for many stock and racing engines. From Paul Yaw's web= site.=20 Now closed down.

Notice that the factory Periphery port timing is more modest than= the=20 "J" bridge port timing. So the Pport actually idles and slow runs smoother= than=20 the bridge ported engines.

=20
Port Timing

IO =3D Intake opens
IC =3D Intake closes
EO =3D Exhaust ope= ns
EC =3D=20 Exhaust closes

US Model First Generation RX-7

= IO 32=B0=20 ATDC
IC 40=B0 ABDC
EO 75=B0 BBDC
EC 38=B0 ATDC
=

European Model First Generation RX-7

= IO 32=B0=20 ATDC
IC 50=B0 ABDC
EO 75=B0 BBDC
EC 48=B0 ATDC
=

First and Second Generation 6-Port 13B

= Primary=20 intake (Part throttle/cruise)
IO 32=B0 ATDC
IC 40=B0 ABDC
Secon= dary=20 intake (Part to full throttle)
IO 32=B0 ATDC
IC 30=B0 ABDC
Auxi= liary high=20 speed ports (Full throttle above approximately 4000 rpm)
IO 45=B0 ATD= C
IC=20 70=B0 ABDC
EO 71=B0 BBDC
EC 48=B0 ATDC

Second and Third Generation Turbo 13B

= IO 32=B0=20 ATDC
IC 50=B0 ABDC
EO 71=B0 BBDC
EC 48=B0 ATDC
=

Racing Beat "Street Port"

= IO 25=B0=20 ATDC
IC 60=B0 ABDC
EO 84=B0 BBDC
EC 48=B0 ATDC
=

Racing Beat "J-Bridge Port"

= IO 115=B0=20 BTDC
IC 72=B0 ABDC
EO 88=B0 BBDC
EC 57=B0 ATDC
=

Mazda Factory Peripheral Port

IO 86=B0 BTDC
IC 75=B0 ABDC
EO 73=B0= BBDC
EC 65=B0=20 ATDC=20
=

= --part1_6dd5a.66059f07.39767a7b_boundary--