cylinder pressure sensor

[Sprocket]

This thread is useless without pictures and data ;D

linky 7 posts up from this one ;)

[gunni]

Literally the most interesting EFI stuff on the internet right now.!!

More info as you progress :)

[ryniobl]

are you triggering off of something? how do you start the logging, reference tdc? spark?

That what you seen on the pictures it was sensor signal caught on oscilloscope,triggered on rising edge.
Now I made a bracket for another VR sensor which shows 6 deg ATDC as a 1st tooth after missing(60-2) on cyl 3 and 4.I wish to have it on cyl no 5 and 2(no5 is prone to knock in BMWs),but it would be a little difficult.
Im very busy last days ,and i need to do some more testing  :) I will show up soon with some new pictures.
Ohhhh man i sleep so little  ;D

MWfire,Tonci have you ordered sensors yet?

[MWfire]

Yes, order is made.

BTW you can use knock integral signal for trigger and set it to tdc.
7th pin of knock chip
http://www.vems.hu/files/genboardv3/v3.3/v33_sch.pdf
http://focus.ti.com/lit/ds/symlink/tpic8101.pdf

[ryniobl]

Yes, order is made.

BTW you can use knock integral signal for trigger and set it to tdc.
7th pin of knock chip
http://www.vems.hu/files/genboardv3/v3.3/v33_sch.pdf
http://focus.ti.com/lit/ds/symlink/tpic8101.pdf

Thanks :) but in this case i use diffrent engine management system.

[[email protected]]

Really you need to plot pressure over crank angle.

[multiplex]

i need to order one of the sensors!  we should get a group buy going  ;D

[ryniobl]

Really you need to plot pressure over crank angle.

That's what i going to do.Now i remove additional sensor and connect another ECU parallel,and set it the way to generate rising edge at 5 deg ATDC on the IGN output.I think it will work  ;D

one more idea was just born in my head :) Can anyone confirm,how much time engine needs to turn the crankshaft by 10 degrees?
I think at 1000rpm needs 1.667ms and at 7000rpm needs 0.238ms.Is this correct?

[MWfire]

Really you need to plot pressure over crank angle.

That's what i going to do.Now i remove additional sensor and connect another ECU parallel,and set it the way to generate rising edge at 5 deg ATDC on the IGN output.I think it will work  ;D

one more idea was just born in my head :) Can anyone confirm,how much time engine needs to turn the crankshaft by 10 degrees?
I think at 1000rpm needs 1.667ms and at 7000rpm needs 0.238ms.Is this correct?

maybee it's better to put 16-18deg ATDC, that is point what you aiming for peak pressure.
10deg= 1/(rpm*6/deg)
so for 1000rpm it is 1.667ms as you write.

[dnb]

BTW you can use knock integral signal for trigger and set it to tdc.
7th pin of knock chip

That is an excellent idea, filed away for future use :)

[ryniobl]

Well...I made it ! :D
I have it tested on the bench.
I going to connect ecu parallel,but using it to generate injection pulse which duration is exactly 10deg at certain rpm.I set rising edge to be at 5deg ATDC,and this way we will see the window which starts with rising edge and ends falling edge.PPP hve to be inside window :D How simple is that!
I have it tested on the bench up to 10000rpms.It seems to be just FINE!and very accurate!
Pictures will come tomorrow.

[ryniobl]

Now I have to find the way to set it on TDC.I was thinking about ultra bright LED diode connected to inj output...

[MWfire]

Now I have to find the way to set it on TDC.I was thinking about ultra bright LED diode connected to inj output...

or use stroboscope

[ryniobl]

Now I have to find the way to set it on TDC.I was thinking about ultra bright LED diode connected to inj output...

or use stroboscope

LED works fine.I set pulse width to 64us,and TDC looks like frozen :)

Here is plot.
blue- 10deg window
red-cyl press(it's on idle ,so you can barely see ppp)

http://picasaweb.google.com/ryniobl77/CylinderPressure#5486072317301739026

for some reason images won't work,so i pasted link

[gunni]

I´m excited !!