Hi Sid I'm not a expert,but I can tell what I do with my plane. I have a Defiant, a 2 engine push/pull. We have 2 engine 0360 as give 200 hp each The front cowling we use in the front are the same hole as from Lancair. They are pretty to look at and the hole are just small. I use 1:3to 3,5 in/out. Work perfect. The rear engine I get some problem with, some ot the cylinder work little to hot. I open up more air out on the top of the cowling, since air in come from botten ot the cowling. Work perfect, and I guess the number are 1:3,5.
My building on my KR go to the stage as I will start to put in instruments. I just love to work with little bird, and I'm looking forward to Meet everone on the gathering. Regard Leif > To: krnet at list.krnet.org > Date: Thu, 30 Jun 2016 15:31:05 -0400 > Subject: Re: KR> Cowling Air Scoop > From: krnet at list.krnet.org > CC: smwood at md.metrocast.net > > I did not have room for an extra oil cooler or one larger oil cooler on the > firewall. So elected to use the Revmaster oil cooler. The Revmaster oil > pump flows 50% more oil; perhaps that does the trick, don't know for sure. > The Revmaster spring temperature regulator does work as advertised keeping > the oil temperature at 170 degrees F. > > The air inlets for the engine cylinders are approximately 2-1/4 x 6 inches > each. Fiberglass ducts direct air to VW metal shrouds ($26 for a pair) > which in turn direct the cooling air down onto the cylinders just like the > Beetle car installation. Definitely use the cool tins too. The single > inlet for the oil cooler, is 2-1/4 x 10 inches. > The ratio of the total areas of inlet area for both the cylinder head > cooling ducts and the oil cooler inlet on the front of the cowl compared to > the single outlet at the bottom rear of the cowl is 1 to 1.45. The oil > cooler inlet is on a flat face square into the wind stream just below the > prop; seemed like a high pressure location to me. The outlet has a ramp at > the bottom of the cowl to get the warm air out into the low pressure > location behind the cowl (inspired by Mark L.). The four exhaust pipes > terminate in two ramps at the bottom edge of the cowl to provide > augmentation of the outlet air flow (similar to the T-34B). I was > definitely avoiding the kind of outlet found on the bottom of Cessna type > cowls; these seem to have a huge hole on the bottom and hope the air gets > out some how. Conventional wisdom says the outlet ratio should be 2.5 to 1. > This is not a pressure cowl, conventional installation. My goal was to > minimize cooling drag. > Cylinder head temperatures vary from one cylinder to another about 10 > degrees F. After about a 5 minute warm up, the head temperatures stabilize > from 340 to 355 degrees F depending on throttle setting. Steve Bennett > recommended 350 degrees F. > > Sid Wood > Tri-gear KR-2 N6242 > Mechanicsville, MD, USA > > > -----Original Message----- > > https://s3.amazonaws.com/expercraft/sidwood/164594493535aecddd7537.jpg > > Hi Sid > I just look at your photo of your cowling, > I just wonder whats the area on the front opening for the inlet of air, > compare to the area back of the cowling? > Regard > Leif > NORWAY > -------------------------------- > > Hello Sid,I was wondering the same question as Leif?Is there a ratio of the > areas?Thanks,Bill Jacobs Daytona Beach, Fl. > -------------------------------- > > Sid,Had same issues with the 7500BTU cooler from GPAS so I bought another > 7500BTU cooler and put them in series.Worked much better.They have a > 15000BTU unit that would have done the trick but I was able to stack the 2 > and may have saved a little space.Tommy W. > > > > > _______________________________________________ > Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. > To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org > please see other KRnet info at http://www.krnet.org/info.html > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options
