X-Junk-Score: 0 [] X-Cloudmark-Score: 0 [] X-Cloudmark-Analysis: v=2.3 cv=PbaBeRpd c=1 sm=1 tr=0 a=QTHwUz1q9nAP9ujD9u6kvg==:117 a=x7bEGLp0ZPQA:10 a=oSMvVwY2MYMA:10 a=y4yBn9ojGxQA:10 a=pGLkceISAAAA:8 a=Ia-xEzejAAAA:8 a=7g1VtSJxAAAA:8 a=OyfnDzLHLuOs9eBpRZsA:9 a=Zbdmt7LtzfXZBXcy:21 a=P5eOi9Aq6TBpgh_c:21 a=QEXdDO2ut3YA:10 a=Qa1je4BO31QA:10 a=gvSQh4r-fQ0A:10 a=-WRATXKxbqRw938MadcA:9 a=N0PPanibduvapXbm:21 a=lcFhg0XvgGrYTNAt:21 a=amvWdCetHf2HgU2j:21 a=Urk15JJjZg1Xo0ryW_k8:22 a=grOzbf7U_OpcSX4AJOnl:22 From: "David Leonard wdleonard@gmail.com" Received: from mail-oi1-f176.google.com ([209.85.167.176] verified) by logan.com (CommuniGate Pro SMTP 6.2.14) with ESMTPS id 611603 for flyrotary@lancaironline.net; Thu, 06 Aug 2020 13:46:56 -0400 Received-SPF: pass receiver=logan.com; client-ip=209.85.167.176; envelope-from=wdleonard@gmail.com Received: by mail-oi1-f176.google.com with SMTP id l84so31085726oig.10 for ; Thu, 06 Aug 2020 10:46:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to; bh=OCM4I0Nz8LT0yfDt5t70Rk+7Vbe8bE+BIla3kUmszDo=; b=mGRXqv94US/7QPZd2FVYD49VHHVqarsjQFuVk1SBMXSGW3Ge7IFY0P/CG6MqaihiUA Hb+nUJLBuxS5a8N2TVscm/zT4GEYkZ0DexmsDKTukW+H25YlbLnVIsYvO34uM/yPYPvo YKXYd0Yoc5YmrQ3FWztNK06opf3EMHyw/XN3TLKIppm0d/XYMddybjjh6m5orGGKx7Ki zOEZMhbcObY3aDL5PM1cqE8KIYqAq2G6d4QuJASqJY9tEJyYxrvEqihUNeIQcGhvxnUA fikm4wuku5O49A6qUCANaGtFpEd7J7Z0OxcV547u0uu1i5GF05WrJp39cvBGFIKyZVc6 KVFQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to; bh=OCM4I0Nz8LT0yfDt5t70Rk+7Vbe8bE+BIla3kUmszDo=; b=kWtdZX/3c+UIhWqGaXHLErNwTHRPI4tL+Wi0ZiBrSy5SDmvqv2vVvxL5PbyJqkxJ01 iUqsiSlA0OWpUTpQ49YshkRLykqJzEzI878v/t+2Fd6abBQvAyMTfVTNqtUTYP1kXnWC YPTl2PVQLlTv0uj//oGZkKERqTJhznUgtPd5EEi3Ft3hTNHqyvboV+zjNstttUE4o3Oz tsbf3YjDVk1TZVY9kcgh0poIQNZzgiRbgwYdY114yaVcNW7oiwPcbuy6Q3kLYfqZ5OMG QNH0FmrdHpDzLw1umdDQymKv5YcyzuBjIZMx59m3z/81w27YzkUDQ4fv3MzuNJ8YvzIk Xg7g== X-Gm-Message-State: AOAM5334idK9Z+fJE8IHxz8sDMY6Dp/A+MwcZIWOay6vWrZ+ew+mSefn f6ngwh7xxSiefWhvQFnInT1YQq4/DHzRvvJHXYXBug== X-Google-Smtp-Source: ABdhPJx701dO8jXmI8a5PWWzjQ/IvcMTyqa2PxnAgD4ulWYgT+m16JwUmW/wmwtXbVmSipiBXA0nZ2Q8VS6qlzU0sw0= X-Received: by 2002:aca:cd84:: with SMTP id d126mr7966941oig.42.1596735997954; Thu, 06 Aug 2020 10:46:37 -0700 (PDT) MIME-Version: 1.0 References: In-Reply-To: Date: Thu, 6 Aug 2020 10:46:26 -0700 Message-ID: Subject: Re: [FlyRotary] Re: Testing best rpm power setting To: Rotary motors in aircraft Content-Type: multipart/alternative; boundary="000000000000f54f5505ac391190" --000000000000f54f5505ac391190 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Bill, I guess you are right about peak power RPM. I have been thinking about turbo, p-port, and highly tuned applications where the torque curve does not drop off as fast. Looks like typical n.a. does indeed peek around 6000-6500RPM. I still maintain that Max RPM should be determined by prop tip speed. Of course, one could always adjust prop length so that redline lands at a desired RPM. Dave Leonard Dave Leonard On Thu, Aug 6, 2020 at 9:17 AM William Jepson wrjjrs@gmail.com < flyrotary@lancaironline.net> wrote: > Steve, > On the dyno you will know better, but on the 4 port (stock) you should se= e > peak power at less than 7k. On the small port version of Powersport=E2=80= =99s > p-port with a similar intake length they were seeing best power at about > 6,500. They may have been slightly over-proped. I would expect a similar > max power with standard side ports. Or possibly even lower rpm. > Bill > > On Thu, Aug 6, 2020 at 7:59 AM Stephen Izett stephen.izett@gmail.com < > flyrotary@lancaironline.net> wrote: > >> Hi guys >> >> I=E2=80=99m wanting to inflight test for the best RPM for peak power of = our 4 >> port Renesis with variable pitch prop (No constant speed control at >> present). >> On Takeoff at Full Fine we hit 6900 after a few seconds and then rpm >> builds to 7400 by 500 feet and 110 KIAS >> I=E2=80=99m wondering if we are well past the peak torque and would be b= etter off >> at a lower rpm. >> >> Am I right in thinking the following would use the aircraft as a Dyno to >> establish rpm for best power? >> >> 1. Set up level flight (auto pilot) >> 2. Maintain WOT and constant mixture (best power - say 0.9 Lambda - 13.2 >> AFR) via Wideband O2 >> 3. Vary RPM in 200rpm increments for 2 minutes each setting between 5600 >> and 7200 by adjusting prop pitch >> 4. Note Fuel Flow and IAS (Logged on Dynon Skyview) >> >> I=E2=80=99m thinking this would give me an indication of best RPM for hi= ghest >> power. >> Our Inlet is just under 19=E2=80=9D long, measured from the side face of= the >> engine. >> So I=E2=80=99m thinking peak torque may be around 6400 rpm. >> >> Your insight would be appreciated. >> Thanks >> >> Steve Izett >> Renesis 4 port RD1C (2.85:1) Inflight Adjustable Prop >> >> >> >> >> >> >> -- >> Homepage: http://www.flyrotary.com/ >> Archive and UnSub: >> http://mail.lancaironline.net:81/lists/flyrotary/List.html >> > --000000000000f54f5505ac391190 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Bill,
I guess you are right about peak powe= r RPM.=C2=A0 I have been thinking about turbo, p-port, and highly tuned app= lications where the torque curve does not drop off as fast.=C2=A0 Looks lik= e typical n.a. does indeed peek around 6000-6500RPM.

I still maintain that Max RPM should be determined by prop tip speed. Of= course, one could always adjust prop length so that redline lands at a des= ired RPM.=C2=A0

Dave Leonard

<= div>Dave Leonard

On Thu, Aug 6, 2020 at 9:17 AM William Jepson <= a href=3D"mailto:wrjjrs@gmail.com">wrjjrs@gmail.com <flyrotary@lancaironline.net> wrote:<= br>
Steve,
On the dyno you will know better, but on the 4 port (stock) you s= hould see peak power at less than 7k. On the small port version of Powerspo= rt=E2=80=99s p-port with a similar intake length they were seeing best powe= r at about 6,500. They may have been slightly over-proped. I would expect a= similar max power with standard side ports. Or possibly even lower rpm.
Bill=C2=A0

On Thu, Aug 6, 2020 at 7:59 AM Stephen = Izett stephen.= izett@gmail.com <flyrotary@lancaironline.net> wrote:
Hi guys

I=E2=80=99m wanting to inflight test for the best RPM for peak power of our= 4 port Renesis with variable pitch prop (No constant speed control at pres= ent).
On Takeoff at Full Fine we hit 6900 after a few seconds and then rpm builds= to 7400 by 500 feet and 110 KIAS
I=E2=80=99m wondering if we are well past the peak torque and would be bett= er off at a lower rpm.

Am I right in thinking the following would use the aircraft as a Dyno to es= tablish rpm for best power?

1. Set up level flight (auto pilot)
2. Maintain WOT and constant mixture (best power - say 0.9 Lambda - 13.2 AF= R) via Wideband O2
3. Vary RPM in 200rpm increments for 2 minutes each setting between 5600 an= d 7200 by adjusting prop pitch
4. Note Fuel Flow and IAS (Logged on Dynon Skyview)

I=E2=80=99m thinking this would give me an indication of best RPM for highe= st power.
Our Inlet is just under 19=E2=80=9D long, measured from the side face of th= e engine.
So I=E2=80=99m thinking peak torque may be around=C2=A0 6400 rpm.

Your insight would be appreciated.
Thanks

Steve Izett
Renesis 4 port RD1C (2.85:1) Inflight Adjustable Prop






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