On 29 Dec 2017, at 7:21 pm, Subscriber Lehanover@aol.com <flyrotary@lancaironline.net> wrote:

I never checked the performance of the radiators. My coolant temp was at the outlet of the block in the thermostat housing. Oil temp was in the fitting where oil entered the engine. Both front and rear main bearings were fed from dash 10 lines.
 
Your ducting looks to be more than adequate for coolant. If the tube is for oil cooling it might need some more thought. Oil cooling at full load is more than one third of the total cooling load. Increasing or decreasing a power setting will show up in the oil temperature first. Oil temps above 160 cost HP.
 
  I would discount results from static testing.
 
 Synthetic oils absorb heat more readily and give it up more readily than conventional
oils. So, the setup becomes more effective with just a product change. Synthetics do not turn into other products when overheated. Such as black snot and road repair sealants, or bits of coal. Apex seal oil should be a brand name 2 cycle oil like RedLine racing 2 cycle. Racing oils have more anti scuff compounds and higher film strength than even synthetic street oils.  Nobody drives a Mazda street car around at full throttle and holds it to 5,000 RPM with the brakes. Only airplane people do that. Button it up and make a few runs up to take off speed. Make movies of the instruments. Then evaluate the cooling.
 
The fellow with the coolant loop picture? Send it to me and I will modify it to work in this format. No problem.
 
Lynn E. Hanover      lehanover@aol.com  A JPEG or BITMAP is fine.
 
In a message dated 12/29/2017 2:42:54 A.M. Eastern Standard Time, flyrotary@lancaironline.net writes:
Hi Lynn
Current testing is stationary.

I have had it on the apron doing figure 8’s and it seemed to not overheat. 
Still to hot though.

Once its moving it seems to help with airflow.

I’m not going to give up on our setup just yet.
I’ve got a few ideas and a bunch of testing and then maybe fly it and see what it does with some wind in its face.

What delta T’s should I expect from the oiling water coolers?
Sounds like 15F on the water and a fair bit more on the oil?

Cheers

Steve Izett



> On 29 Dec 2017, at 10:07 am, Subscriber Lehanover@aol.com <flyrotary@lancaironline.net> wrote:
> 
> Are these cooling tests being done at speed, say 60 to 70 MPH? Or, stationary?  It only needs to cool long enough to get to the runway. Put some tufts on wires right behind the prop and long enough to get into the ducting. I bet almost nothing flows into the ducting. Mount a pancake fan behind the radiator to cool on the ground. Some of the spiral flow from the prop will defeat the straight sides of the ducting. Ram air at flying speed is completely different. Most added temperature shows up in the oil with high    power settings. The racer cooling at low speed is just not adequate. But once you hit the first straight and go over 100 MPH
> (top speed 146) the cooling is great. Make one change at a time. Make it a big change. Record the instruments on video. Just like running the dyno. Run a bit rich on the ground. Say 1600 degrees or less EGT. This will help a bit.
> Lynn E. Hanover
>  
> In a message dated 12/28/2017 7:55:29 P.M. Eastern Standard Time, flyrotary@lancaironline.net writes:
> Steve
> 
> I suspect it’s #2. Steve B’s email has a wealth of information and points to airflow. To prove it layup a quick but reasonable shaped duct and test it with the cowl off. I would start with a 28 sq or large inlet. 30% of the core face would be a good place to start testing. 
> 
> I’ve only seen Tracy takeoff in the RV8 once. But he was not using anywhere near full throttle. He did a lot of work on the inlets but I’m not sure he can use all 300HP in the summer.  
> 
> Bobby
> 
> 
> 
> Sent from my iPad
> 
> > On Dec 28, 2017, at 5:13 PM, Stephen Izett stephen.izett@gmail.com <flyrotary@lancaironline.net> wrote:
> > 
> > Hi Guys
> > 
> > Thanks for the replies
> > 
> > Our water inlet is small (Standard Glasair) - modelled of Tracy’s RV8 20b 
> > I understood he had a round right cheek inlet of 5.25” giving him 22 in^2 to his water rad for 300hp in Florida temps. 
> > For the two rotor -> 2/3rd of 22 is <15. We have >16 for <200hp
> > 
> > My concern is the delta T’s.
> > Yesterday at 1800rpm I was seeing 12F across oil and 6F across the water. Previously I’d seen this as high as 18F and 9F not sure why so low yesterday.
> > What do others see on the ground at idle?
> > Does anyone have good pressure data on the ground. Idle and power settings?
> > 
> > Are these low due to:
> > 1. Water flow due to cooling system design or air trapped.
> > 2. Air flow due to small inlet, compounded by a prop that doesn’t have much blade near the spinner. 
> > 
> > I’ll look at some further baffling of the Rad to exit but cant see this helping at idle air speeds unless I duct the exit low pressure direct to the back of the core.
> > 
> > I’ll send further photos
> > Thanks
> > Steve
> > 
> > Steve<3.JPG>
> > <Cowl exit.jpg>
> 
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