X-Virus-Scanned: clean according to Sophos on Logan.com Return-Path: Sender: To: lml@lancaironline.net Date: Mon, 07 Jan 2008 00:29:54 -0500 Message-ID: X-Original-Return-Path: Received: from imo-m28.mx.aol.com ([64.12.137.9] verified) by logan.com (CommuniGate Pro SMTP 5.2c4) with ESMTP id 2631569 for lml@lancaironline.net; Fri, 04 Jan 2008 21:52:25 -0500 Received-SPF: pass receiver=logan.com; client-ip=64.12.137.9; envelope-from=Sky2high@aol.com Received: from Sky2high@aol.com by imo-m28.mx.aol.com (mail_out_v38_r9.3.) id q.c50.1f993d3e (65097) for ; Fri, 4 Jan 2008 21:51:38 -0500 (EST) From: Sky2high@aol.com X-Original-Message-ID: X-Original-Date: Fri, 4 Jan 2008 21:51:38 EST Subject: Re: [LML] Re: One mag, One electronic ignition X-Original-To: lml@lancaironline.net MIME-Version: 1.0 Content-Type: multipart/alternative; boundary="-----------------------------1199501498" X-Mailer: AOL 9.0 VR sub 5006 X-Spam-Flag: NO -------------------------------1199501498 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit In a message dated 1/4/2008 6:56:41 P.M. Central Standard Time, glcasey@adelphia.net writes: The possibility that Steve suggests below is probably real, but remember that the electronic ignition will only advance when the manifold pressure - and hence the cylinder pressure - is lower than the max (only at high altitude or part throttle). And the electronic ignition will only advance 5 or so degrees more than the mag anyway. In 5 or 10 degrees the cylinder pressure will not rise much. Gary, Because I am running at a 9:1 CR, my base timing is 20 dBTDC. Light Speed EI recommends that 20 dBTDC base timing for engines operating with CRs greater than 8.7:1. At 80% to 110% my timing is less than 25 dBTDC. At 25**2 the timing is right around 25 dBTDC. At race power, 2750 RPM, 30" MAP, I typically see 21 or 22 d BTDC. At low power settings enforced by high altitudes, thus reducing my WOT MAP, I see 28-30 dBTDC or so. At idle power settings, say 10-12" MAP, 900-1100 RPM, I generally see 34+ dBTDC. It all works out very nicely. That means my timing span is as much as 34 degrees, depending. I did a great number of experiments with the LASAR ignition where I would fail the EI in flight, reverting to the fixed timing mags and compare the results. Too bad I didn't have any timing data on the EI function. Also, note that I now use the LSE (Light Speed) EI system. Scott Krueger AKA Grayhawk Lancair N92EX IO320 SB 89/96 Aurora, IL (KARR) Pilot not TSO'd, Certificated score only > 70%. PS: Colyn, FYI see LSE timing data listed above. **************Start the year off right. Easy ways to stay in shape. http://body.aol.com/fitness/winter-exercise?NCID=aolcmp00300000002489 -------------------------------1199501498 Content-Type: text/html; charset="US-ASCII" Content-Transfer-Encoding: quoted-printable

In a message dated 1/4/2008 6:56:41 P.M. Central Standard Time,=20 glcasey@adelphia.net writes:

<= FONT=20 style=3D"BACKGROUND-COLOR: transparent" face=3DArial color=3D#000000 size= =3D2>The=20 possibility that Steve suggests below is probably real, but remember that=20= the=20 electronic ignition will only advance when the manifold pressure - and hen= ce=20 the cylinder pressure - is lower than the max (only at high altitude or pa= rt=20 throttle). And the electronic ignition will only advance 5 or so deg= rees=20 more than the mag anyway. In 5 or 10 degrees the cylinder pressure w= ill=20 not rise much.

Gary,

Because I am running at a 9:1 CR, my base timing is 20 dBTDC. Lig= ht=20 Speed EI recommends that 20 dBTDC base timing for engines operating wit= h=20 CRs greater than 8.7:1. At 80% to 110% my timing is less than 25=20 dBTDC. At 25**2 the timing is right around 25 dBTDC. At race pow= er,=20 2750 RPM, 30" MAP, I typically see 21 or 22 d BTDC. At low power setti= ngs=20 enforced by high altitudes, thus reducing my WOT MAP, I see 28-30 dBTDC= or=20 so. At idle power settings, say 10-12" MAP, 900-1100 RPM, I generally=20= see=20 34+ dBTDC. It all works out very nicely. That means my timing sp= an=20 is as much as 34 degrees, depending.

I did a great number of experiments with the LASAR ignition where I wou= ld=20 fail the EI in flight, reverting to the fixed timing mags and comp= are=20 the results. Too bad I didn't have any timing data on the EI=20 function. Also, note that I now use the LSE (Light Speed) EI syst= em.=20

Scott Krueger=20 AKA Grayhawk
Lancair N92EX IO320 SB 89/96
Aurora, IL (KARR)

Pil= ot=20 not TSO'd, Certificated score only > 70%.

PS: Colyn, FYI see LSE timing data listed=20 above.

Start the year off=20= right. Easy ways to stay in shape in= the new year.

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