ESE's works engine tuner

[jonny quest]

Is there a thread with dyno pictures? I'm thinking of building a inertia rear wheel dyno that also will run off counter sprocket for an engine stand. Curious to what others have done.

TZ, can you slow down the sampling rate. Just for a test to view trace? Or is sensor itself just not fast enough? Would 2 sensors measuring same pressure and average be useful?

[husaberg]

Is there a thread with dyno pictures? I'm thinking of building a inertia rear wheel dyno that also will run off counter sprocket for an engine stand. Curious to what others have done.

TZ, can you slow down the sampling rate. Just for a test to view trace? Or is sensor itself just not fast enough? Would 2 sensors measuring same pressure and average be useful?

Yes...........
https://www.kiwibiker.co.nz/forums/s...78284-DIY-dyno
prob here also
https://www.kiwibiker.co.nz/forums/s...highlight=dyno

there more but it must be in buried in other threads

if you look in wobbly's pic near the start there is a pic go to that post.
https://www.kiwibiker.co.nz/forums/s...post1130542420

[Carel H]

Attachment 341782

So I put the oscilloscope on the crankcase pressure sensor tonight, purple line, yellow line is the ignition pulse. I wanted to see what sort of signal it produced and what it looked like compared to EnginMod's prediction. Pretty close I recon. The next move is to try and capture a trace at 12,000 rpm.

Looks like a slow sensor. 4000 rpm/min / 60 seconds = 66.6 rps (revolution per second). Scope shows 11 sample changes with the same increment/decrement in that period.
11 * 66.6 = 733 changes per second. (responsetime 1.4 msec). At 12000 rpm this will be ~4 samples per period.

There is no peak, just increment/decrement, so there is a dampening. I guess the swing will increase with decreasing rpm.

[TZ350]

Looks like a slow sensor. 4000 rpm/min / 60 seconds = 66.6 rps (revolution per second). Scope shows 11 sample changes with the same increment/decrement in that period. 11 * 66.6 = 733 changes per second. (response-time 1.4 msec). At 12000 rpm this will be ~4 samples per period. There is no peak, just increment/decrement, so there is a dampening

Many thanks for your comments. I have no previous experience with this sort of pressure sensor so I was not sure what I was looking at. But sure was not expecting discreet steps, I was expecting a more analog signal from the pressure sensor. I have no trouble making software reads at the right time in the crank cycle but four distinct steps at 12,000 RPM from the pressure sensor may not be a very good representation of the pressure cycle in the crankcase.

Anyway if I can I will try and get a picture of what the pressure sensors output looks like at 12,000 rpm, this might take a night or two. And when I have a test setup that makes good traces then I can search/test for a sensor that better suites what I am trying to do.

[TZ350]

Low RPM

Higher RPM

I still have not been able to make a definitive trace at 12,000 rpm yet, Crap fuel mapping issues. But it is becoming obvious that I will need to take the high pressure reading at BDC and the low reading at TDC, so that is helpful to know.

[sispeed]

Hello. I'm building a Aprilia RS250 for Race use and I like to use spark plugs like the r7376. Original it is a BR10ECMIX and this one is a little bit shorter.
Do you know of any alternatives to the original type in R7376 Style with the thin ground electrode?
Thank you
Regards Siggi

[TZ350]

Engine Mods crankcase pressure simulation and a trace taken at much the same conditions. The trace is certainly recognizable from the simulation. Unfortunately the slow speed of the crankcase pressure sensor distorts the trace at higher RPM but I think that once I know that the trace is consistent and what its shape looks like I will be able to adjust my software to use it.



As the RPM increases the number of pressure points decreases and I am sort of expecting that there will be 3 at 12,000 and maybe only 2 at 13,000 RPM. I think I will still be able to work with 2 so long as they are consistently the highest and lowest reading and always appear in the same place.



Plan "B" is to use a Ceramic Piezo. These are very dynamic and give off a proportional voltage as long as the pressure on its face is changing. So it might give a fast and continuously analog signal. Anyway that is plan "B" if I need it.

[Carel H]

Engine Mods crankcase pressure simulation and a trace taken at much the same conditions. The trace is certainly recognizable from the simulation. Unfortunately the slow speed of the crankcase pressure sensor distorts the trace at higher RPM but I think that once I know that the trace is consistent and what its shape looks like I will be able to adjust my software to use it.



As the RPM increases the number of pressure points decreases and I am sort of expecting that there will be 3 at 12,000 and maybe only 2 at 13,000 RPM. I think I will still be able to work with 2 so long as they are consistently the highest and lowest reading and always appear in the same place.



Plan "B" is to use a Ceramic Piezo. These are very dynamic and give off a proportional voltage as long as the pressure on its face is changing. So it might give a fast and continuously analog signal. Anyway that is plan "B" if I need it.

I had a look on an MAP sensor, the functional block describes how it "slices" at 1khz and explains the not connected steps in your scope photos. The speed is there, but not the conversion speed. I already suspected it, there must be a conversion somewhere in the sensor.

Have a look at page 11, look at the A/D conversion, correction, D/A conversion, then look at your scope and see the handicapped potential.

https://www.infineon.com/dgdl/Infine...2af6ab37f00b3a

So an alternative is to work more near the component level with the Freescale MPX or Honeywell pressure sensors.
They convert pressure into an analog signal. Period.

Piezo transducers and pressure sensors are close family. But the piezos work at a resonant frequency and they need a very good designed housing to work properly. In my opinion a can of worms.

[Niels Abildgaard]

12000 rpm is 200 rps and with ten points per cycle to get reasonable measurements You are in 2kHz michrophone country.
Condenser michrophones can be very cheap and unlinear but that is not a problem here methink.

[katinas]

Hello. I'm building a Aprilia RS250 for Race use and I like to use spark plugs like the r7376. Original it is a BR10ECMIX and this one is a little bit shorter.
Do you know of any alternatives to the original type in R7376 Style with the thin ground electrode?
Thank you
Regards Siggi

Hi
Tested some different spark plugs on RGV 250 ( like RS 250 ), and looks like with standard angled spark plug head and std. ignition (SAPC 22D30, 23D00), non resistor plugs add some power.

Non resistor std. hex plugs
Denso IW06 ( iridium-platinum thin )
NGK R5184 ( gold palladium-platinum thin)
NGK R6061 ( nickel alloy- nickel alloy standard ground, but spacial conical inside shape and ground electrode position, maybe is very eligible for std, complicated, head with angled spark plug)

With modified straight plug position head and adjustable ignition ( ignitech, zeeltronic) on RGV/RS, resistor plugs like NGK R7376 or short R7282 with TRS 1225 cap. is very good.

With thin platinum ground electrode, on Denso is possible to adjust gap, NGK not.

[wobbly]

The R7376 is a "normal " insulator length plug ( and thus uses a cheap 5K plugcap ).
It has an iridium fine wire center electrode and a Platinum fine wire ground electrode.
This is identical to the Honda RS125/250 NGK plug R7282 in its nose configuration but the Honda version is a short insulator type.
The Honda plug is 4x the price and the special plugcap costs more than the plug.
Its also available with longer threaded body to enable use of an under plug deto sensor.
Is there no room for the longer/cheaper R7376.

[TZ350]

Ok, not quite 12,000 RPM but it tells me everything I need to know. That the signal is consistent and instead of measuring at the theoretically correct crank angles I can allow for the delay in the sensor and measure the crankcase high pressure at BDC and the low pressure at TDC. Easy as.

[sispeed]

Hello Katinas and Wobbly. I managed, with a little fiddling, to install them.
So I think this should be fine.
Thanks for Reply and hints.
I have straight Head inserts but Std Ignition at the moment

Regards Siggi

[Flettner]

TM and I thank those that assisted in trying to stop KTM patenting TPI. It seems their application has been turned down by the patent office.

[DoldGuy]

TM and I thank those that assisted in trying to stop KTM patenting TPI. It seems their application has been turned down by the patent office.

Flettner, Do you know “Why” they were denied? If so, did your previous design, installed & working have an effect?