Scroll down and read only what you need.Very interesting how this guy calculate to determine the runner lenghts.
Further down on runner lenght calculations they talk about the Renesis motor runner lenght.
Yes this is for car use but there is a lot of info what we need for tuning the rotary on the “sweet spot” rpm.
The aquistic waves and speed of the intake air is very interesting

Regards

Sent from my iPhone
Le Roux Breytenbach

On 02 Apr 2021, at 00:52, Charlie England ceengland7@gmail.com <flyrotary@lancaironline.net> wrote:

Hey Le Roux,

I think your iphone ate your homework. ;-)

Part of the message seems to be missing.

Charlie

On 4/1/2021 4:35 PM, Le Roux Breytenbach breytenbachleroux@gmail.com wrote:

Check this thread about intake runner lenght,anwers on a lott of 13B engines and intake runner lenght and

Sent from my iPhone

Le Roux Breytenbach

On 01 Apr 2021, at 19:23, Charlie England ceengland7@gmail.com <flyrotary@lancaironline.net> wrote:

4 port or 6 port? It's been a long time since I had the manifold off the engine, but I *think* my 4 port engine has same size pri & sec ports. I know I used the same size tubing to make the manifold. I believe that the '3rdary' ports on a 6 port are smaller, but I think Steve Boese found that they don't do anything at our more reasonable rpms.

Charlie

On 4/1/2021 12:05 PM, Finn Lassen finn.lassen@verizon.net wrote:

Thanks Ed.

What I meant to say is that Tracy implied that secondary runners should have a larger diameter.

But I made them the same (inside diameter) as the holes in the block (30 mm).

Finn

On 4/1/2021 11:07 AM, eanderson@carolina.rr.com wrote:

Smaller dia may mean that airflow velocity is higher than in the primaries and since the secondary valves open at higher rpms, the higher airflow velocity may help stuff more air into the chamber give the shorter duration the port is open at higher rpm.  Just a WAG.

Ed

------ Original Message ------

From: "Finn Lassen finn.lassen@verizon.net" <flyrotary@lancaironline.net>

To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>

Sent: 4/1/2021 8:48:31 AM

Subject: [FlyRotary] Re: MISTRAL

Tracy remarked on my secondary runners being smaller diameter than primaries and now I see the same here.

If I recall correctly, when I calculated the area of the secondaries vs the area of the primaries (in the engine block) I got smaller secondaries than primaries.

What gives?

Finn

On 3/31/2021 9:44 PM, Kelly Troyer keltro@gmail.com wrote:

Primary Runner length approximately........24 inches

Primary Runner "OD"  approximately.........1.40 inches

Secondary Runner length approximately.....24 inches

Secondary Runner "OD" approximately.......1.66 inches

--

This email has been checked for viruses by Avast antivirus software.

https://www.avast.com/antivirus

--

Homepage:  http://www.flyrotary.com/

Archive and UnSub:   http://mail.lancaironline.net:81/lists/flyrotary/List.html

--
Homepage:  http://www.flyrotary.com/
Archive and UnSub:   http://mail.lancaironline.net:81/lists/flyrotary/List.html