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MembersPage/JimW (2006-03-16 04:43:08)

Switching to Genboard on my Golf racer before next season, because K-Jet isn't cutting it. Later on I will be doing forced induction, so I need room for change.

Pictures and some info:

http://proton.shadowflux.com/vwracing/

email james at shadowflux dot com

I see the manual has been updated regarding ignition and injection h[] sequences, which helps a lot. Crystal clear now. One question - how does one disable ignition and injection driving completely? I want to connect to all sensors while old management system is working to test everything and do some datalogging before implementing v3.2, but don't want to actually run engine with it. Set h[] arrays and ignchmax/injchmax to all zero and leave coils/injectors disconnected?

More config related questions:

1. What is crank_minper?

2. battfac: amount of time to add per X volts decrease in supply voltage. What is X?

3. Is injpwmt the same as injopen?

4. Does calibrating the TPS in Megatune take care of the values (tps_low, tps_high) in config?

5. TPSDOT should be used only with Alpha-N for acceleration enrichment?

MAPDOT should be used only with Speed-density for acceleration enrichment?

6. What are valid values for tps_thresh? Can tps_thresh be less than tpsdotrate[0]?

7. Is tpsasync the 't' in delta over time (tps/map DOT) or the amount of time to add the acceleration enrichment?

8. Why don't we apply warmup enrichment to acceleration enrichment instead of seperate bin (as acmult and tpsacold)?

9. Does batt_cal change fueling or just readings in MegaTune/MegaTunix?

10. Should fastidle be set to target idle rpm when not using IAC?

11. What is iac_step_seq?

12. ve_learn_conf bit2=2x2 box. Isn't this only an 2 byte variable? What are valid settings here?

0x02=2x2 mode?

0x01=1x1 mode?

0x00=ve_learn disabled?

Config

Latest/revised comments config: MembersPage/JimW/Config

I have edited a config file and would like to submit it for review. I hope it will be an improvement on the one everyone has been using.

There are many questions I could not find answers to on the wiki, all denoted in CAPS.

Notes about subsystems (to verify/justify config variables) on pages below

My installation to date:

Testing, experimenting, and learning with Genboard/PC.

Starting a new job, so time and money have been in short supply. More parts and testing are necessary before installation is complete.

When uploading the firmware via avrprog: Click 'Exit' after finished uploading, window greyed and only available action is to click X to close (no matter how much time passes). Was worried that the upper bits would not be written to flash, but everything seems okay. Update (3/18): Have repeated this several times and everything works out okay.

I am trying to learn how to edit the XML manual. Tonight was the first night I've even had a chance to look at it, and it doesn't seem too bad. A few questions that probably aren't appropriate on the manual pages:

what is the preferred editing method/program? I'm using Morphon and its very slow (on computer .... MHz, ... RAM and OS .... ). P4 1.4ghz, 384mb rambus rdram, win2k. Not a slow machine, never have trouble with anything else I want to run (don't play games on this machine, so exclude those processer hogs)
- Morphon was preferred, but any text or XML editor works. Just keep to the DocBook format and it'll be fine.

Please split historical info from the uptodate project pages: the latter must be thematically organized.

My Genboard and LCD display currently:

36-1 crankwheel and crank trigger setup on spare (and dirty) engine block:

```[http://proton.shadowflux.com/vems/crank_sens_mtd.jpg]``` [1]

```[http://proton.shadowflux.com/vems/sens_block.jpg]``` [2] ```[http://proton.shadowflux.com/vems/sens_gap.jpg]```

[3] ```[http://proton.shadowflux.com/vems/crank_trigger_machined.jpg]```

[4] ```[http://proton.shadowflux.com/vems/crank_trigger_mounted.jpg]```

Here you can see the TDC mark in the pulley aligned with the missing tooth. You are looking at the back of the pulley, so from this angle it would rotate counter-clockwise.

The TDC is 15 degrees after the center of the missing tooth.

..so we set up the sum of trigger_tooth + ign_tdcdelay for 195 degrees.

Offsetting 180 degrees is absolutely reasonable because max ignition advance is limited by ign_tdcdelay. 15 degrees of max ignadv is not enough. Actually, ign_tdcdelay should be at least 30 crankdegrees larger than ignition advance at cranking. Common ign_tdcdelay values are 55..65 degrees.

igntdc_delay=0x1e (30 decimal, that is 15 crankdegrees) is very bad, see above. trigger_tooth=00 and igntdc_delay=0x1e, at n[]=0, the coil would fire at TDC, yes. But you might not be happy with max advance of 15 degrees, and timing from previous tooth would be active even for very low RPMs (where RPM variations are significant => BAD for dwell precision at lowRPM).

let's assume a normal tooth=10 crankdegrees (=360/36 if it's 36-1)

We are using 36-1, so tooth-tooth spacing is 10 degrees.

trigger_tooth=0d (decimal 13), that is 13*10=130 crankdegrees because one tooth is 10 degrees.

trigger_tooth=00 means the tooth after the missing tooth will act as the trigger. Please correct it whereever you see it wrong.

ign_tdcdelay=82 (decimal 130, which is 65 degrees)

This results in realistic n[] values, if TDC is 130+65 (=195=180+15) degrees after the first tooth after missing tooth. Adjust trigger_tooth in the first place, and only fine-tune with ign_tdcdelay (you can keep it in 60..70 degrees range, which is ideal)

Mik uses a similar missing-tooth placement.

Intake Air Temperature Sensor

Using Bosch air temp sensor, part number 0 280 130 085. Sensor comes from a VW 1.8t 20 valve, small port head.

Values in EasyTherm are:

50F=4800ohm

82F=1900ohm

208F=230ohm

Still have to test these values to be certain but thats what I have now. I believe these are +/-2F of actual temp.

Note about Megatune: When tuning sensors it is not necessary to recompile and upload firmware each time. Simply update the .inc files in the Megatune directory and watch values change in Megatune. Recompile and upload firmware when values are correct.

I am now looking for sensors and other hardware.

Two MSD 8224 (GM DIS) coils for the ignition. These coils have two blade terminals which control charging and firing, just like any other wasted spark coils out there.

I am using the GM ignition module as a mounting base - it is already built and provides connection to the coils. I pryed the back off of the module and ground the electronics out of it. I then wired the inside so that the Weatherpack connector wires directly to the coil blade terminals. I would have a picture of the inside of the base, but I didn't think to take any pictures before I epoxied it back together. duh.

Aqua colored lines indicate wires I added after removing the guts.

All others indicate already present internal connections. Pin A on 6-pin connector used for +12VDC, Pin B for charging/firing coil #1, Pin C for charging/firing coil #2.

Picked up a Ford (Echlin brand name actually) VR sensor and trigger wheel from NAPA auto parts. I will be having the trigger wheel machined flat on one side and precision drilled to bolt directly to the timing belt pulley on the crank. Those of you using the Ford VR sensor: which terminal is wired to which pin on EC36 for correct polarity?

Any VR sensor pinout info near EdisIgnition ?

GND signal VR-
primary_trigger VR+

It makes sense to verify with InputTrigger/TriggerLog even if it works (my connection, done according to the polarity in the docs was reversed).

Trigger wheel: NAPA PN# CSS304

VR Sensor: NAPA PN# CSS400

Notes:

[history of Samuel].