> In a message dated 9/13/2004 9:13:30 AM Central Daylight Time, keltro@att.net
> writes:
>
> << Lynn,
>
> Could we have some clarification here.......Your previous post
> indicated
> that you are measuring oil temp of your race car in the pan and that you do
> not like to see temps over 190 degrees.......If this is the case some of the
> group
> that are flying may be getting between the devils fence and his front door
> with temps of 200 to 240 degrees "After" the oil cooler...... With that in
> mind
> how important do you think replacing the stock spring loaded rotor cooling
> jets with fixed Weber (or equivalent) jets and/or the rotor bearings with the
> racing (more clearance) version considering the rpm and power that we are
> asking of the engine (N/A) in our aircraft?
> As usual we really appreciate your no nonsense real world experience...
>
>
> Kelly Troyer
>
> Dyke Delta/13B/RD1C/EC2
>
>
> I actually measure cooled filtered oil as it enters the engine. (see the
> picture). I have another gage in the oil storage tank to give me a measurement
> on
> the pressure side cooler performance. I do not know what the spent oil temp
> is, in the "pan." We have no pan. Just a flat plate. (about 20 degrees drop
> from the pressure side cooler) We have a video camera recording two EGT gages,
> scavenged oil temp, RPM, voltage and water pressure.
>
>
> The jets in the crank are larger than the Weber .180MM or .200MM that the
> racers replace them with. ??????
>
> There is a spring loaded ball below that jet nut that shuts off cooling oil
> flow to the rotors at low RPM. This allows for rapid warm up, and keeps good
> oil pressure at idle RPM. When the revs go up, and more oil pressure is
> available from the pump speed increase, the increased pressure, and centrifugal
> force
> lift the balls off of the oil port, and rotor cooling oil spray begins
>
> So what is the change to a fixed (smaller) jet for?
>
> When you race the car with big ports and lots of overlap, the idle ends up
> around 2000 RPM just to get it smooth enough to deal with. So the pump is
> turning fast enough that the "no" oil pressure at idle is not a factor. It will
> have
> close to normal oil pressure. But if you install a modified oil pressure
> relief valve to get the oil pressure up to 115 pounds, and then start using the
> engine close to 9,000 RPM, the stock crank jets are too big, and too much of the
> extra oil pressure is wasted being sprayed into the rotors. It cannot cool
> the rotors to any additional amount, and it just foams the oil more than normal.
> So the (smaller) jets reduce the pressure loss and the excessive oil sprayed
> into the rotors, when well above stock oil pressure is used. I use Weber 180
> main jets. Idle is 2,200 RPM. We shift at 9,600 RPM. Idle oil pressure is 85
> PSI. Off idle to 9,600 oil pressure is 100 PSI.
>
> On the Nopistons list, many of the kids do this modification, and then lament
> the idiot light blinking at hot idle. There is no stress on the bearings at
> all at low speeds and any oil at all is enough. So I tell them to tape over the
> light and forget about it. When they scream the engine, the oil pressure is
> right up where it belongs and there is no problem.
>
> I helped a local guy with some welding on a Dyke Delta, and have a set of
> plans. I built up an expanded Dyke Like design in electrical conduit. I love
> that
> look and the performance is impressive. But just too much work for me. I
> think race car fuel cells in the wing roots would be better than 47 gallons
> behind
> my head. There are so many things I would change that it wouldn't be a Dyke
> when I got done. But I digress.
>
> Lynn E. Hanover
>