Honda K Series Discussion

[Fred]

Firstly, K20A2 as mentioned in another thread. I dug up some pictures, and it would be nice to confirm or deny what these are applicable to.





It would appear that it is probably 12 on crank with some sort of sync or more on the cam shaft(s). The question is, two, one on each cam, or just one, and how many pulses, with what alignment? If anyone can fill me in on the details, I could add support when someone wires a FreeEMS up to one.

Fred.

[Fred]

Also, is the VTEC in these variable or pin on/off based like all of the earlier stuff? If variable is it simply PWM like late subarus and others?

[Fred]

Word from Mr Blundell himself is that they have dual sensors and both VTEC and IVTEC with dual profiles and PWM variable cam timing. I'm curious to know what feedback is available from the cam sensors for angle, if any, and any details on how the OEM stuff functions internally.

[beboo]

i would like to help with the development of a honda k20 system. the cheapest solutions is about $1000 (Hondata)

on the k motor:
each cam has its own cam sensor.
I-vtec is 2 parts . 1- vtec solenoid 12 volts to activate. 2- Variable Timing 0-50 deg , i believe its pwm


let me know if u need more information or pictures of stuff . i have a extra k20 head laying around.

[beboo]

this is a interesting read
http://www.k20a.org/forum/showthread.php?t=85125

[Fred]

Great link!

That guy says 12-1 but the signal shows 12+1 as the OP states. I wonder if it was a typo?

It would be great to have photos of the actual wheels involved for all three signals and their relative timing as a three trace image at the same time.

This is definitely going to require specific custom code. That's not a problem, however other things are a priority and it will be a little while before we have support for this. I probably won't start trying to implement it until someone has hardware attached to a running engine that they can steal a signal from in parallel with an OEM ECU. If we're in that position then we can make real progress with code to interpret these signals in the way required to do all of the fancy valve actuation stuff properly.

This will also require specific hardware, however I'll talk to my man about that tomorrow morning and see if we can include it in his work.

Fred.

[Jpolanco]

well I know this is not completely part of the k series but here it goes. I have a running engine on the stock ecu and as soon as I have the necessary hardware for the logging I will be more than happy to help this happen.

On the other hand I am not sure when I'll be able to get the necessary hardware.The advice that I have found is to wait until there is and official and standard board for all installation (or at least that is what i understood from one of Fred's post).

Juan

[DaWaN]

The first picture showing the CKF sensor is wrong, the picture is from a D-series engine, a completely different Honda engine with a completely different ECU compared to the Honda K-series.

I will look into the sensors now, but I can almost confirm that it uses PWM for cam phasing and a switch for VTEC engagement

[DaWaN]

OK I checked Service manual and Part catalog:
VTEC is through solenoid (8 ohms), on or off and VTEC works on both cams
VTC is through solenoid (8 ohms), PWM and on intake cam only, can advance intake cam up to 50 degrees

You have 3 sensors:
CKP : Crankshaft position, this is a 12+1 tooth wheel and is mounted on the crankshaft
CMP : Camshaft position, this is a 4 tooth wheel and is mounted on intake cam (does measure VTC degrees)
TDC (CMP2) :Top dead centre (camshaft position 2) : this is a 4 + 1 tooth wheel and is mounted on the exhaust cam

According to the service manual the CKP is used for ignition timing and injection as well as for detecting misfires, the TDC is only used for cyl 1 detection and the CMP is used for camshaft position

[Fred]

FANTASTIC info, DaWaN! Thank you very much.

Jpolanco - in terms of running an engine, probably for the best, yes. In terms of logging, if you have the cash, all you need is a development board and some power supply and sensor interface stuff and you're already useful. It's up to you, I have plenty of other stuff on my plate right now, and for a while to come, but it's definitely doable, I have the code in my head already :-)

PS, I put in a request for the new hw to have support for this setup. Consider that done.

Fred.