BTW I don't think the 15 thou run out on the end of the
e-shaft is the cause of the miss. At what RPM is it missing?
I think you should borrow my RX8 trigger wheel hub and test
the EC2 with out the engine running. I think it has a software
problem over about 6500 RPM. You won't need the water pump
for that as they engine will not be running. If the injector
pulse width is not getting wider that is the problem.
In fact come to think about it I suspect Tracy's system
quits working after the torque peak as it is based solely
on manifold press and max HP comes well after peak torque
AND peak man press. If it has trouble sensing RPM
over 6000 it will not feed the additional fuel needed into
the engine at the same man press at the higher RPMs. Particularly
since you moved the torque peak down.
A car EFI systems uses a mass air flow sensor so
air flow is proportional to RPM as WELL as throttle
opening.
That explains a lot.
We need to hook up the Hytek and see what is going
on in Tracy's system over 6000 RPM with out the engine
running.
It is like trying to determine what some one is thinking
solely by observing their actions :) The hood is welded
shut :)
I have an early EC2 from the days when nobody went over
6000 RPM. Tracy has changed the software from that time.
We tried it on the p-port eng on the dyno but could not get
it tuned. We gave up at $650 a day and put the Weber on.
Perhaps we were having the same problem.
It might be interesting for me to hook it
up with the CAS simulator and see what it does
with my scope.
The bottom line is what does yours do?
Paul Lamar
Paul,
I agree, it would be very helpful to do a bench test on my EC-2. Bobby
Hughes has a scope we can use and I'm pretty sure I can rig it up using my
trigger wheel and my router/speed controller. Bob Darrah could fab an
adapter to fit my router.
There are two reasons I think this may be related. First, I can get
different results by changing the gap between the timing wheel and CAS
pickup. Second, Tracy recently commented that he had a misfire caused by
vibration of his CAS trigger bracket. He built a stiffer bracket and the
miss was gone. As I see it, a wobbling trigger wheel would cause the same
symptoms.
So, I think I will finish installing the Renesis water pump with new crank
hub and see if there is any improvement in how it runs. I can then do the
bench test if it still runs poorly. Keep in mind that before changing
engines this ignition setup would give me 7200-7300 rpm during the first
few seconds of my takeoff run. So, something has obviously changed, I
just
don't know what it was.
It may be that my exhaust system is too restrictive and is causing exhaust
gases into the intake charge at higher rpm. Lynn Hanover has stated that
the P-port engines don't tolerate exhaust restriction well. That makes
sense as a restrictive exhaust could force exhaust gases into the adjacent
intake during the overlap period. Come to think of it the rpm at which
the
engine began rough-running dropped after I installed the new muffler. I
may be on to something here... So, this may not even be ignition
related after all.
One question, what size air inlet should I have feeding the three 1-7/8"
ID
runners? Currently, I have a 3" SCAT hose with K&N filter.
Mark
I'll loan you my hub. No need for Bob to make one.
Well if you just go on area alone three runners are 8.28 square inches.
3 inch scat is 7 square inches. There is also skin friction drag pressure
loss in the tube due to velocity squared so I would go up a size or two.
There is 3.25 OD and 3.5 OD SCAT and SCEET.
SCAT is rough inside. SCEET is smoother but the inner liner
has been known to come adrift and plug it up. If you switch to
SCEET sew the inner liner to the outer liner with small diameter
safety wire.
Thin wall aluminum tube is best but I think about 3.5 inches OD would be
needed. You might want to roll your own out of .025" thick aluminum.
Send me some pictures of the P-port version of the 3 rotor.
Paul Lamar
Paul,
I've enclosed two pictures that show how it all came together.
You've confirmed that I need to enlarge the size of the intake tube.
Maybe
I can get some mandrel bent aluminum tubing and weld the pieces together
so
that I only have two small pieces of flex hose.
Mark
Nice tangential muffler.
Can you get a Harbor Freight inspection camera up the exhaust
pipe far enough to see the small holes in the center pipe?
Some could be failing.
Also nice job on the K&W duct on the oil cooler.
Can I see a picture of the other side of the engine? :)
Burns Stainless has some .065 wall 3.5 inch OD aluminum
90 degree bends for $105. Too expensive and too
heavy.
Carve it out of Styrofoam, wrap with vinyl electricians
tape and make a layup. The foam can be dissolved with acetone
and the tape fished out.
Paul Lamar
Paul,
Yes, I have a Harbor Freight LCD inspection camera and use it regularly.
I
can work it up the exhaust to where I can see a few inches into the
muffler. So far, everything appears to be in tact internally.
Mark
The muffler looks pretty good from the outside. How many holes
in that center tube and what is the diameter of the holes?
In other words what is the total area of the holes?
Somebody, I forget who, said that tangential mufflers can build
a complex internal pressure field due to the internal vortex.
The center of the vortex is low pressure while the outside
of the vortex is higher pressure. If this is true the center
of the field will be cooler as well. You might be able
to verify this with one of those non contacting infrared hand held
temperature gauges. The outer part of the vortex would then
apply more back pressure on the engine. That is the theory anyway.
Therefore you might try a separate 2 inch down pipe from the outside
of the can leading out, down and back. Make it temporary so it can
be removed and plugged up if it does not help. Leave this for
later after you have analyzed the electrical situation with the Hytech.
Robin is out of town on biz but I may be able to come down for a day
or two next week. Remind me to bring my infrared temp gage.
Paul Lamar
Paul,
That is a generous offer, but I work days (M-F) and our daughter is coming
to town Wed through Monday (6/16 - 6/21). I'm not sure what all they
have planned, but I really want to spend some time with her. She lives in
Denver, so I don't get to see her very often.
I need to order parts in order to get the opto-isolator board wired up and
ready to go. You mentioned a Panasonic part, do you have the p/n?
The tube running through the tangential muffler has 109 slits made with a
carborundum cutting disc (too &^%*$# difficult to drill holes in
inconel). The holes were then spread apart with a punch to form a bunch
of
diamond-shaped holes. So, I would guess that the holes are 1" long and
3/8"
at the widest. I realized too late that it would have been better to
angle
the slits to "encourage" the gasses into the inner pipe. I figured I
would compensate for that by using lots of holes (slits). I had thought
about adding an extra exit, or two. Or, I could open it up and replace
the
2.5" inner pipe with a larger pipe. Or, I could remove the inner pipe
altogether.
Mark
I sent the jpg with the pin number on it.
Did you not get it? Here it is again.
It is a Digi Key CNS 7s something. 77 cents each.
Your muffler could be acting like an air compressor
with the hot air swirling around what amounts to a bunch
of cowl flaps. Air could be flowing into the exhaust pipe :)
Just add another exit and see if it helps.
Paul Lamar
Paul,
OK, the opto's are on their way.
Mark
At 250 RPM and .05 inch the signal is 5 volts peak to peak.
If the engine starts it must be close enough.
The scope picture is one half of a revolution.
Paul Lamar
Paul,
What is the output voltage at around 7k rpm with a gap of .0050?
Mark
About 25 volts peak to peak but don't try to cut that down. That
is Tracy's job.
The picture says it all. The upper character line line
on the scope say it is 1 volt per division but
I am using a 10X probe so it is really 10 volts
per division. Hence 25 volts.
The sweep is set to 1 ms per division
so as you can see there are about 8 division
between rotor one and back to rotor one. 8 ms
is about 7500 RPM.
Anything you might do to preserve the
wave form AND cut it down will affect the engine starting.
Set the EFI computer up on the bench. You can simulate the injectors
with a high wattage 5 ohm resistor connected to 12 Volts.
The bottom of the resistor will be switched on and off by
Tracy's computer. Use opto circuits on the injector signals and
feed them into the digital inputs on the Hytek.
Connect the CAS simulator. No need to connect
the manifold pressure sensor hoses at this time. Leave them open.
That simulates WOT.
I think you have other problems and nothing to do with the CAS.
If you are using an MSD ignition or something like that
you can use the Hytek to check the integrity of
the signal coming out of Tracy's computer.
Set the Hytek (poor man's storage scope) sample rate
to 50,000 samples per second.
You only need to run it for a few seconds as it will
acquire a mass of data on your hard disk very quickly.
This way merely checks to see if the ign pulse
is going out in a timely fashion. In that case use
opto circuit and feed the 5 volt output pulses to digital inputs
on the Hytek. The data will show any missing pulses
if any and the width if it is greater than. 1/50,000
of a second.
Paul Lamar
Paul,
I think you mentioned that you had a spare CAS sensor. Would you mind
tossing that in the box with the trigger wheel adapter? The A/C sensor is
hard wired and potted, so I really don't want to have to remove it if I
don't have to.
I had a thought about how to spin the trigger wheel. I have a Shopsmith
wood lathe. The speed is infinitely adjustable. I'm pretty sure that I
can
rig up the trigger wheel so that I can control the rpm very precisely.
We'll see how that works out later.
Mark
Too late. Box went out this morning.
The way to check those things is use an ohm meter.
I think there is an RX8 shop manual on:
http://foxed.ca/foxed/index.php?page=rx7manual
The other way of checking the internal magnet is see if it is
attracted to steel or iron. How many standard washers
will it pick up from a given height.
Go to pep boys and buy one of these for $25.
Just as good as a Mazda $100 pick up.
They all work the same way. Many turns of fine
wire wound around a magnet.
This appears to be the hot tip place to buy
them on the internet.
http://www.pronto.com/user/search.do?displayQuery=abssensor&SEM=true&query=abssensor&adid=1189375855-3014077-0_gs&ref=abs
sensor&creativeid=3254163062&site=
Here is a screen capture of the front page of that web site.
Don't buy anything you can't see a picture of.
The Borg Warner ABS101 part number appears to be obsolete.
Mine looks like the BWD $84 ABS112 but I only payed $16 at Pep Boys.
Print a picture and take it to the auto parts store with you.
Paul Lamar
Paul,
I ordered a spare sensor from Atkins Rotary.
Mark
How much did he charge? Was it used?
Use this chart as a guide and go to your local
pull your own part junk yard.
I'll be surprised if the CAS turns out to be the
problem. Those devices are very robust. There is
no current flowing through them to speak of so
they don't burn out. I suspect they would have
to be in a fire to destroy them.
Paul Lamar
Paul,
I agree, they're very robust, but I wanted a spare that I could experiment
with. It was listed on EBAY for $35, less than half of a new one.
The first one I purchased was listed for a Mazda Protoge - cam angle
sensor.
It is identical to the rotary CAS, but was much cheaper. Someone must
have
gotten wise because now the Protoge sensor is the same price as the rotary
unit... RockAuto.com for $75/ea.
Mark
They all use the same tech. A magnet with some wire wound around
it.
It would be a good biz for someone un employed. Go to junk
yards and collect all kinds of sensors, clean them up and
sell them on ebay.
You could also make your own out of the off the shelf
table lamp parts, magnet wire and magnets. Use a drill motor
to wind the coils. I think I wrote this up but I can't
find the message.
Paul Lamar
BTW Craig I measured the resistance of the stock pick up.
It appears to be 1.2K Knowing the resistance of 32 ga
magnet wire per foot one should be able to calculated the number
of feet of wire required. I think it is .16 ohm per foot.
If so you will need 7000 feet.
http://www.bcae1.com/wire.htm
http://amasci.com/tesla/wire1.html
ALSO SEE: WIRE SUPPLIERS, HV CABLE & DIODES
AWG Dia-mils TPI Dia-mm Circ-mils Ohms/Kft Ft/Ohm Ft/Lb
Ohms/Lb Lb/Kft *Amps MaxAmps
0000 459.99 2.1740 11.684 211592 0.0490 20402
1.5613 0.0001 640.48 282.12 423.18
000 409.63 2.4412 10.405 167800 0.0618 16180
1.9688 0.0001 507.93 223.73 335.60
00 364.79 2.7413 9.2657 133072 0.0779 12831
2.4826 0.0002 402.80 177.43 266.14
AWG Dia-mils TPI Dia-mm Circ-mils Ohms/Kft Ft/Ohm Ft/Lb
Ohms/Lb Lb/Kft *Amps MaxAmps
0 324.85 3.0783 8.2513 105531 0.0983 10175
3.1305 0.0003 319.44 140.71 211.06
1 289.29 3.4567 7.3480 83690 0.1239 8069.5
3.9475 0.0005 253.33 111.59 167.38
2 257.62 3.8817 6.5436 66369 0.1563 6399.4
4.9777 0.0008 200.90 88.492 132.74
3 229.42 4.3588 5.8272 52633 0.1970 5075.0
6.2767 0.0012 159.32 70.177 105.27
4 204.30 4.8947 5.1893 41740 0.2485 4024.7
7.9148 0.0020 126.35 55.653 83.480
5 181.94 5.4964 4.6212 33101 0.3133 3191.7
9.9804 0.0031 100.20 44.135 66.203
6 162.02 6.1721 4.1153 26251 0.3951 2531.1
12.585 0.0050 79.460 35.001 52.501
7 144.28 6.9308 3.6648 20818 0.4982 2007.3
15.869 0.0079 63.014 27.757 41.635
8 128.49 7.7828 3.2636 16509 0.6282 1591.8
20.011 0.0126 49.973 22.012 33.018
9 114.42 8.7396 2.9063 13092 0.7921 1262.4
25.233 0.0200 39.630 17.456 26.185
AWG Dia-mils TPI Dia-mm Circ-mils Ohms/Kft Ft/Ohm Ft/Lb
Ohms/Lb Lb/Kft *Amps MaxAmps
10 101.90 9.8140 2.5881 10383 0.9989 1001.1
31.819 0.0318 31.428 13.844 20.765
11 90.741 11.020 2.3048 8233.9 1.2596 793.93
40.122 0.0505 24.924 10.978 16.468
12 80.807 12.375 2.0525 6529.8 1.5883 629.61
50.593 0.0804 19.765 8.7064 13.060
13 71.961 13.896 1.8278 5178.3 2.0028 499.31
63.797 0.1278 15.675 6.9045 10.357
14 64.083 15.605 1.6277 4106.6 2.5255 395.97
80.447 0.2031 12.431 5.4755 8.2132
15 57.067 17.523 1.4495 3256.7 3.1845 314.02
101.44 0.3230 9.8579 4.3423 6.5134
16 50.820 19.677 1.2908 2582.7 4.0156 249.03
127.91 0.5136 7.8177 3.4436 5.1654
17 45.257 22.096 1.1495 2048.2 5.0636 197.49
161.30 0.8167 6.1997 2.7309 4.0963
18 40.302 24.813 1.0237 1624.3 6.3851 156.62
203.39 1.2986 4.9166 2.1657 3.2485
19 35.890 27.863 0.9116 1288.1 8.0514 124.20
256.47 2.0648 3.8991 1.7175 2.5762
AWG Dia-mils TPI Dia-mm Circ-mils Ohms/Kft Ft/Ohm Ft/Lb
Ohms/Lb Lb/Kft *Amps MaxAmps
20 31.961 31.288 0.8118 1021.5 10.153 98.496
323.41 3.2832 3.0921 1.3620 2.0430
21 28.462 35.134 0.7229 810.10 12.802 78.111
407.81 5.2205 2.4521 1.0801 1.6202
22 25.346 39.453 0.6438 642.44 16.143 61.945
514.23 8.3009 1.9446 0.8566 1.2849
23 22.572 44.304 0.5733 509.48 20.356 49.125
648.44 13.199 1.5422 0.6793 1.0190
24 20.101 49.750 0.5106 404.03 25.669 38.958
817.66 20.987 1.2230 0.5387 0.8081
25 17.900 55.866 0.4547 320.41 32.368 30.895
1031.1 33.371 0.9699 0.4272 0.6408
26 15.940 62.733 0.4049 254.10 40.815 24.501
1300.1 53.061 0.7692 0.3388 0.5082
27 14.195 70.445 0.3606 201.51 51.467 19.430
1639.4 84.371 0.6100 0.2687 0.4030
28 12.641 79.105 0.3211 159.80 64.898 15.409
2067.3 134.15 0.4837 0.2131 0.3196
29 11.257 88.830 0.2859 126.73 81.835 12.220
2606.8 213.31 0.3836 0.1690 0.2535
AWG Dia-mils TPI Dia-mm Circ-mils Ohms/Kft Ft/Ohm Ft/Lb
Ohms/Lb Lb/Kft *Amps MaxAmps
30 10.025 99.750 0.2546 100.50 103.19 9.6906
3287.1 339.18 0.3042 0.1340 0.2010
31 8.9276 112.01 0.2268 79.702 130.12 7.6850
4145.0 539.32 0.2413 0.1063 0.1594
32 7.9503 125.78 0.2019 63.207 164.08 6.0945
5226.7 857.55 0.1913 0.0843 0.1264
33 7.0799 141.24 0.1798 50.125 206.90 4.8332
6590.8 1363.6 0.1517 0.0668 0.1003
34 6.3048 158.61 0.1601 39.751 260.90 3.8329
8310.8 2168.1 0.1203 0.0530 0.0795
35 5.6146 178.11 0.1426 31.524 328.99 3.0396
10480 3447.5 0.0954 0.0420 0.0630
36 5.0000 200.00 0.1270 25.000 414.85 2.4105
13215 5481.7 0.0757 0.0333 0.0500
37 4.4526 224.59 0.1131 19.826 523.11 1.9116
16663 8716.2 0.0600 0.0264 0.0397
38 3.9652 252.20 0.1007 15.723 659.63 1.5160
21012 13859 0.0476 0.0210 0.0314
39 3.5311 283.20 0.0897 12.469 831.78 1.2022
26496 22037 0.0377 0.0166 0.0249
AWG Dia-mils TPI Dia-mm Circ-mils Ohms/Kft Ft/Ohm Ft/Lb
Ohms/Lb Lb/Kft *Amps MaxAmps
40 3.1445 318.01 0.0799 9.8880 1048.9 0.9534
33410 35040 0.0299 0.0132 0.0198
------------------------
From richard.quick at slug orgSat Sep 2 13:01:29 1995
Date: Mon, 28 Aug 1995 22:24:22 -0600
From: Richard Quick
Reply to:
usa-tesla@usa.net
Subject: AWG Wire Chart
AWG D.C. OHMS WIRE DIAM APPROX. TURNS PER FEET PER
SIZE PER 1000 FT INCHES INCH, SOLID ENAMEL POUND
COVERED
1 .1264 .2893 X 3.947
2 .1593 .2576 X 4.977
3 .2009 .2294 X 6.276
4 .2533 .2043 X 7.914
5 .3195 .1819 X 9.980
6 .4028 .1620 X 12.58
7 .5080 .1443 X 15.87
8 .6405 .1286 7.6 20.01
9 .8077 .1144 8.6 25.23
10 1.018 .1019 9.6 31.82
11 1.284 .0907 10.7 40.12
12 1.619 .0808 12.0 50.59
13 2.042 .0720 13.5 63.80
14 2.524 .0641 15 80.44
15 3.181 .0571 16.8 101.40
16 4.018 .0508 18.9 127.90
17 5.054 .0453 21.2 161.3
18 6.386 .0403 23.6 203.4
19 8.046 .0359 26.4 256.5
20 10.13 .0320 29.4 323.4
21 12.77 .0285 33.1 407.8
22 16.20 .0253 37.0 514.2
23 20.30 .0226 41.3 648.4
24 25.67 .0201 46.3 817.7
25 32.37 .0179 51.7 1031
26 41.02 .0159 58.0 1300
27 51.44 .0142 64.9 1639
28 65.31 .0126 72.7 2067
29 81.21 .0113 81.6 2607
30 103.7 .0100 90.5 3287
31 130.9 .0089 101 4145
32 162.0 .0080 113 5227
33 205.7 .0071 127 6591
34 261.3 .0063 143 8310
35 330.7 .0056 158 10480
36 414.8 .0050 175 13210
37 512.1 .0045 198 16660
38 648.2 .0040 224 21010
39 846.6 .0036 248 26500
40 1079 .0031 282 33410
41 1323 .0028
42 1659 .0025
43 2143 .0022
44 2593 .0020
45 3348 .00176
46 4207 .00157
47 5291 .00140
************************************************************************
For winding Tesla secondary coils the general consensus is to use
number 22 AWG, or larger diameter, double Formvar Magnet wire. Often
surplus partial spools of odd wire sizes are found, so I took time to
post a more complete chart of AWG numbers and fractional diameters
than is usually available. All information above is approximate
despite the decimal places. Wire diameter, turns per inch, resistance,
feet per pound, etc. all vary slightly from one manufacturer to another.
Insulation thicknesses will vary depending upon type and the supplier.
Turns per inch will also vary with the quality of the winding. In
practice, Tesla coil windings are not perfect (nor do they need to be)
so expect some slight variations from the specification table above.
Richard Quick
Paul,
Unfortunately, there are no Pick-Your-Part yards in the Austin area. The
nearest Pick-Your-Part is 100 miles away in San Antonio.
Mark
Did you read Tracy's message I just sent? Apparently Tracy's
method of detected TDC or what ever angle he wants
depends on the exact polarity of how the crank angle sensor is wired.
Did he send instructions on this subject? Yours could be wired wrong.
Paul Lamar
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