flyrotary@lancaironline.net Mailing List Archive

In a message dated 6/21/2005 6:36:36 PM Pacific Standard Time, 13brv3@bellsouth.net writes:

You tend to forget some very important points Rusty, please remember I'm working on aluminium end/side housings ( without ports) - so too is Richard Sohn. It is much easier and cheaper to do it that way. So naturally we need a port somewhere.

Right you are. I did sort of gloss over that part. I think I understand now. You're doing the PP because it's easier, not because it's better. Wait, maybe that didn't come out quite right :-)

Cheers,

Rusty (stirrin' up trouble)

Hi Rusty,

I guess I'll stir up some more by mentioning the Paul Lamar helped with the PP engine recently that was duplicating the LeMans timing and port sizes. PP sizes that is. They got 228 HP at less than 7000 RPM (13B). With a cobbled up carb manifold no less. (I believe the Madzatrix guys were helping with the carb) They hadn't prepared the FI and had to go with somthing familiar. (Dyno time costs) That is no small potatoes right out of the box. 114 HP per rotor at less than 7k which would indicate that the intake they used could see a great deal of improvement. For high power you will play hell getting the HP of the PP engine even with the renesis IMO. Not that you can't do it but you will need a GOOD TUNED MANIFOLD and will probably need to run the higher RPM of the typical Renesis 9K redline. The side ports are a compromise to allow good power and low end torque. Aircraft wise I am going to be looking to buy or build 3 PP housings for my 20B. Much simpler manifolding, (3 pipes instead of 6) and better power at typical RPMs. I would like to limit my engine to 7000 if I can to reduce wear if nothing else. Plus if aluminum side and intermediate housings become available I could have a 40 pound weight savings!

Bill Jepson