The attachments are those you sent on 11/18/2009.

 I'm working on my own engine control and some questions arose as I
 referred to the attached data.
 The pressure tap data from Rotor 1 and Rotor 2 do not appear 180 degrees
 out of phase, and the phase difference varies with rpm. Could this be
 from different lengths between the two lines from ports to sensors?
 In the photo "Apex-oil-hole-data.jpg", the sensor plotted by the yellow
 line appears to be saturating at 4.1 volts. Is that sensor in the apex
 oil hole, or is it in the intake ports?

 It would appear that in order to prevent pressure waves from saturating
 the sensor, it needs either to have a range considerably above one
 atmosphere or the volume of the line from the pressure tap to the sensor
 needs to be high enough to damp out the variations and provide an
 average pressure.

 What model sensor is used to provide the red and blue plots?
 Just an observation, but it would seem that the peak pressure at the
 location you are recommending for the pressure tap should be a valid
 indicator of the air charge. In order to have a volumetric efficiency of
 120%, it would seem that the pressure would have to reach 120% of
 ambient, and would be seen by the sensor connected there. If so, then
 the MAP sensor peak output would account for VE, or be closely
 proportional to it. An op amp configured to output the highest voltage
 applied to it could then be used to provide an output proportional to
 air charge.


 Victor Roberts

 In the photo Apex-oil-hole-data.jpg The yellow line is the CAS signal.
 That is just the timing reference to 20 degrees BTDC.

 We damp the pressure variations from the apex sealing
 oil hole with a tiny hole in the pressure tap fitting.

 That is a Free Scale pressure sensor. The 120% VE has
 been verified on the dyno.

 This engine was not generating full power as it had
 a fixed pitch prop. It would not see full power until
 the prop tips ran into the sonic wall and with the
 throttle wide open and then only if the engine
 happened to be generating peak torque at that RPM.

 What ever pressure one reads there just needs to
 be consistent and repeatable as the mixture is adjusted
 in software for whatever power that measurement
 represents. In other words it may not represent
 the average mass of air going into the engine. It may
 not be the average manifold pressure.
 Whatever it is it works very well with Tracy's
 EFI system as the engine runs smoothly through out
 the rev range.

 Our intention here was to study the organ pipe
 tuning effect. Most of the pressure measurements were
 made in the wall of the runner close to the rotor housing
 for this purpose. The response of the pressure sensors
 is only rated at one milli second. We were sampling at
 the rate of 1000 samples per second.

 Any phase discrepancy could be due to the data acq system as it does
 only one pressure measurement at a time and that may take as long
 as .1 ms second or 100 micro seconds or longer because the data must
 be sent to the notebook computer serially.

 However we are the world wide leaders in this technology
 as I know of no other organization doing this kind of applied
 R&D. If they are doing it they are not publishing it to
 my knowledge.

 Necessity was the mother of invention in this case.

 Paul Lamar


 Paul,

 Do the brass oil injectors [nozzles] have any type of
 one way valve in them or are they simply a shaped nozzle?
 I have been trying to take them out without any luck.


 Doug in Japan


 Are you talking about the brass orifice (jet) in the bottom
 of the 10 mm threaded hole? I would leave then in there
 and make sure they are not plugged up.

 The oil nozzles have one way valves and we looked into
 using them. It is just not practical. The way they work is
 the pressure on the rotor housing side is below atmospheric
 so they automatically suck apex seal oil in assisted by
 the air flowing in the one way valve. The apex oil metering
 pump is not pumping anything. It merely presents
 oil to the oil nozzles at atmospheric pressure.

 The one way valve prevents oil flowing out the the
 air tubes that are connected to the intake system
 beyond the throttle down stream of the air filter.
 The oil nozzles do the injecting. Actually when
 you fully understand this you realize the oil nozzles
 are not the best for continuous high power. OK for cars.
 In that case it is much much better to mix the apex seal
 cooling oil with the fuel IMHO. More fuel more power
 more apex seal oil.


 Paul Lamar


 Paul,


 Is there any reason I can't put the oil filter between the oil pump and
 oil cooler?
 That way I can mount the filter on the firewall and use a large one along
 with an oil accumulator since my oil pan is so small. Heat might be an
 issue.

 Doug in Japan

 No I think that will work. The pressure the oil cooler sees will
 be reduced somewhat. I have no record of anybody doing that before.

 BTW every time you pump oil through a right angle at high flow rate
 you add heat to the oil and reduce the pressure. You can eliminated
 two of them by taking oil directly out of the front end housing.
 This is a Lyn Hanover modification. Rumor has it it will reduce
 the oil temp by 10 or 20 F. Use a straight thread tap and O ring
 fitting. A pipe tap could crack the front housing.

 Paul Lamar

Hi Doug;
Filtering before the oil cooler is preferable if the cooler can handle
the pressure - you probably want at least 150 psi rated for cold
northern starts.
Look at 3rd gen or Rx8 coolers.
For oil filters, Lynn explicitly recommended against certain brands such
as fram (that is another topic)
I believe he also recommended synthetic straight weight 40 weight oil in
the sump + 2stroke pre-mix in the fuel, unless you fly in the frigid
northern climates in winter like here.
Cheers
Cary

For others:
#1 is the standard rear oil inlet
#2 is a racing mod to provide additional oil flow to the front main
bearing (this will interfere with side mount alternators).
#3 new oil pump outlet. (replaces #4 and several 90degree oil passage bends)
#4 original oil pump outlet. It is capped in this image to allow output
from the new outlet #3 above to reduce the number of 90degree bends.


Cary,


Thanks. I recently came across this Fluidyne oil cooler which I can
mount up out of the way from the plugs. The single flow through will
reduce oil backpressure a little.

http://www.customcarscentral.com/fludb30618-universal-all-makes.html


I don't see anything in my notes about recommended filters. I would
appreciate a suggestion.

Doug in Japan

Size - 21x5.875x3.''; Dry Weight - 12lbs; Fittings -
(2) AN-12 & (2) AN-6 & (1) 3/8'' FNPT; Oil Capacity - 1.21Qts

That looks near identical in size to the 2nd gen RX7 oil cooler.
Do they have any real heat transfer data available other than
"it worked in Buba's NASCAR racer"? :)

Paul Lamar

Paul

At first glance I thought the same until I noticed it was 3 inches thick
not 2" like the RX7 oil cooler.  BTW I have two of the RX-7 coolers  in
my workshop that I'll sell if the new one works.  I am  waiting for an
answer from Fluidyne on the specs.  Bubba did say it worked real fine
until his car crashed on the first curve.  Something about a stuck slide
throttle I think:)

The inspiration to try this cooler came from your illustration of the RV4
on your web's sites first page on 'Building the Motor Mount' section.
  If the arrangement  works it could save on a lot of oil hose lengths
and give me easy access to the spark plugs. The filter before the oil
cooler will see more pressure if a dual pass oil filter is used.  In any
case wisdom dictates I  find an oil filter with a robust construction
both inside and out. Going bigger than the standard palm size unit
should help filter the oil as well.

The outlet from the oil cooler could go to a small manifold mounted on
the existing filter stand.
The lower inlet could be plugged.  Oil to the bypass valve would descend
in this arrangement.

Running an additional oil hose back for a straight-in shot to the rear
bearing implies the existing oil gallery to that location is too
restrictive or the balance of oil flow is somehow wrong.  Well the dowel
gallery is large so it must be from there down.  Can the passage be
modified? I am not a big fan of additional oil hoses, especially when
several right angle fittings are used creating the same restriction we
want to solve.

It would seem better to take oil for the accessories like turbo-charger
and PSRU right from taps  off of the oil cooling tanks letting the front
bearing see the full pressure of the oil gallery.

Doug in Japan

Slide throttles are outlawed in NASCAR. Four barrel carbs only.
I did notice they have to cool the valve springs or they break.
Let us know what data fluidyne sends you on those coolers.

Paul Lamar