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Re: Honda K Series Discussion

Posted: Wed Dec 14, 2011 11:30 pm
by Jpolanco
What exactly would I need to buy (yes I want to be helpful :)) and I am not in a hurry is just that i have fell in love with the idea of free ems and want to contribute as much as I can. The K engine would be great to attract more people as was mentioned before. I do have soldering skill but have never work with surface mount. Any way if you have a code in your mind I think you should know that the factory ecu use different tables when it switch cam angle and vtec. it has tables for low cam speed as hi cam speed (when the vtec kick) If I remember correctly from hondata the use 2 spark tables 2 fuel tables 2 cam angle tables all of this hi speed rotation or low speed are what triggers for the variable tables (vtec is included in the descripton).


Juan

Re: Honda K Series Discussion

Posted: Thu Dec 15, 2011 10:23 am
by Fred
Great! Yep, I'm aware that the honda ECUs use lots of tables. FreeEMS has room for lots of tables, so you're covered! I just need to sort out a really good way to configure and access and connect them to the right things. Algorithms for switching between two tables at VTEC switch point or interpolating with cam timing are pretty easy to implement, so that's not a problem at all.

The hard part will be getting that code in my head working and working well.

The process for development will be staged and something like this:

Can read RPM/Position
Can start and run with fixed cam timing/profile
Can run with VTEC engagement at X RPM
Can run with VVT under closed loop control
Can run with both VVT and VTEC operating - mission accomplished.

Please be aware that this engine is probably the most difficult to support thus far, so this will take a while to nail down properly.

What can you buy? You can buy any XDP512 development card with a 2k SM for loading code and adapt some external circuits to it to interface with the car. The TA is probably still the best choice, see this ancient but still useful thread:

viewtopic.php?f=62&t=471

Fred.

Re: Honda K Series Discussion

Posted: Thu Dec 15, 2011 10:26 am
by Fred
If you're not in a hurry you could also just wait and get some sort of real FreeEMS specific EMS hardware sometimes next year. There should be some variety available :-)

Re: Honda K Series Discussion

Posted: Thu Dec 15, 2011 7:26 pm
by Jpolanco
Got it then I'll wait. Just wanted to point out that I am able and happy to test in order to support the growth oh freems community.

Re: Honda K Series Discussion

Posted: Thu Dec 22, 2011 10:11 pm
by beboo
sorry for the late reply.
i will post some pictures of the trigger wheel and cam wheels later this week.
i just remembered i had a logic analyzer that i can use to sniff the CKP,CMP and TDC signal. hopefully i will post the results this week.

Re: Honda K Series Discussion

Posted: Thu Dec 22, 2011 10:33 pm
by Fred
Awesome! :-)

Re: Honda K Series Discussion

Posted: Sun Feb 12, 2012 12:42 am
by beboo
i upload the TBC and CKP wave forms , tell me what u think

Re: Honda K Series Discussion

Posted: Sun Feb 12, 2012 2:13 am
by Fred
Can you please roll with explicit "crank and "exhaust cam" and "intake cam" for the sensor names, i hate those acronyms. I can guess that your "CP" is the exhaust cam (from the pattern, cp doesn't make it obvious), but i'm totally unsure about the "tdc" one. What are these exactly? :-)

Edit: Also "tell me what u think" Please use full words here, at least for common stuff like "you". Cheers.

Re: Honda K Series Discussion

Posted: Sun Feb 12, 2012 6:21 am
by beboo
tdc is on the exhaust
and cp is crank positioning sensor

Re: Honda K Series Discussion

Posted: Sun Feb 12, 2012 1:48 pm
by Fred
OK, you seem to have contradicted what I thought and what DaWaN posted earlier. The cp.jpg file that has four wide pulses and a narrow one is where? On the crankshaft or on a camshaft and if a camshaft which camshaft? And the tdc.jpg file is on which of those also? Earlier posts said that the exhaust camshaft sensor had a 4+1 pattern like your cp.jpg file. Also, earlier posts said there were three sensors. Please be more explicit and clear, it saves everyone time :-)