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Posted: Sun Jan 30, 2005 9:57 am
by joey
bmacf wrote: Don't forget to ground the MS case or else you'll lose the processor like I did!

Bill
cheers ! on teh up side, good enuff reason as any to upgrade to MS-II ! :wink:

Posted: Sun Jan 30, 2005 10:19 am
by bmacf
Joey, regarding the DB37 connector, check out the figure that was posted on alfagtv6.com from msefi.com:

http://www.alfagtv6.com/bb/files/extwir.gif

If you really want to see my harness, be prepared, its ugly! Those connectors in the picture are solderless twist on connectors from Swenco. They are available at NAPA here on the east coast of the US. I was having a hard time soldering a wire to the Ljet header, twisting it with the other wires, and getting the length right so that when I soldered it to the DB37 it wasn't excessively stressed. Kinda a mess, will keep it for now.


Image

I started in June 2004 - don't feel bad because it takes time!

Bill in MD

Posted: Sun Jan 30, 2005 11:40 pm
by joey
thanks bill ! that diagram is really helpful as well...

i also like the idea of the connectors incase you muck up, tho i can see how that would be hard to fasten on one you've done a couple.... perhaps some type of snap on connector would be better, an insulated spade connector perhaps? i'll have a look around..

also, does anyone think grounding yourself to a bare PC case while its running with a wrist strap is bad? i dont think having the computer on will matter.

Posted: Mon Jan 31, 2005 3:07 am
by bmacf
Joey, the PC case is grounded, so go ahead and ground yourself to the case. When I built my MS board the only time I was worried about electrostatic discharge (ESD) was when I was putting in the processor. Perhaps there's another esd sensitive component or two-anything packaged on esd protective foam or packaging.

Let us know how it goes.

Bill in MD

Posted: Mon Jan 31, 2005 3:45 am
by David
Joey, Bill,

Static discharge ?? What's that? Just kidding. I never worried about it.
I cut off the L-Jet pins in the case and left enough for small spade connectors. Only a few $$ for a bag of 12. I then used heat skrink to cover the spade connectors. I made a couple of mistakes with the pinout, but the spade connectors were easily changed.

I'm going to spray the whole lot with circuit board sealer.

Another issue was the com port connection to a laptop. I used a USB to Com cable converter and my new Dell laptop connected without problem.

David

Posted: Mon Jan 31, 2005 5:53 am
by joey
thanks guys !

yeah, myself, i was pretty hamfisted with computer bits and such in teh past, i just touched the PSU case and called it good.. but man - the way the MS manual craps on about ESD scared me.. looking up google for another reference didn't help with the nerves, something like
"ESD is the cause of most failures that are extremely hard to diagnose, handle with extreme care, you've been warned twice for a reason" (they've taken out shares in wrist straps perhaps?)

anyway ! guys, i'm up to the R10 bit.. my MS checks out sweet until now ! actually i did have a problem ! belive it or not, i installed the serial chip (U6) incorrectly and so the communications test with the MS connected to the stim didn't work... boy that was trouble desoldering all dem pins and swapping ends.. gguuhhh ! (prolly shouldn't have done this late late last night !)

anyway, i waste characters to pose a question.. i was gunna start a poll - but this will do !

what do you guys recommend for r10? it seems that most of us have found that not even 1.6K is sufficient ! reading the other thread, 2.2K seems the default step for these alfas, and i know you bill ended up needing 3.3k !!

if in theory i wanted to use this ECU for another car, is there a draw back for going to such a high OHM level? the MS manual recommends strongly against upping the resistance arbitarily unless its needed... obviously its needed for the alfa - would it have an adverse affect on something else? (or is this more sensationalist fluff?) in other words, i'ld like to know why we cant pick a big r10 to begin with if it cuts out interference... is 3.3k a good number to start of with? or try 2.2k first? obviously having taken out the u6 i aint scared of a mere resistor, but i'ld like to know the difference all the same..

cheers, thanks for all the help guys ! i was so proud when my MS learnt to count and read voltage !

cheers,

joe

Posted: Mon Jan 31, 2005 12:28 pm
by P.Webb
2.2k should be fine for most applications. The warning is for the non-transistorized ignitions that don't have the 400v spikes. If it's reading directly off coil(-) there isn't much to disturb it. This is the scheme for them old points type ignitions.

The L-Jet, and subsequently your MS is getting the tach signal from the Bosch ignition box. The Hall sensor is providing crank angle to the ignition box which turns it out to pin 1 of the L-Jet.

Look at pages 5-23 and 5-24 of the factory manual. There's a really good diagram.

My Cardisc copy was garbage so I had someone scan the page for me hi-res so I could read the pin numbers. This is gearing up to some kind of Motronic ignitor ignition from the Hall sensor before I blast the EDIS on there. I have to do the 2 race cars before I do mine. Time is running thin and those guys are bugging me to get their cars on the dyno.

-Peter

Posted: Mon Jan 31, 2005 12:30 pm
by P.Webb
BTW, I'm running 3.3 in my car too. I get a small occasional spike but not enough to worry about.

I also noticed the tach signal is a little worse when cold. I find cleaning the connector to the ignitor, coil and Hall sensor helps clean up the signal too. And my dash tach reads somewhat sorta accurate too :)

-Peter

Posted: Mon Jan 31, 2005 1:33 pm
by Michael
First road test was pretty bloody good considering I've not touched the tuning yet - using Steve's 3.0 msq file with the horrible AFM still untouched.

I'm still battling the tach spikes too - I have a 1.6Kohm in R10 but will try a 3.2 and see if that helps.

I agree with the observation that the spikes are worse when the car is cold ... and in my case, at low revs. I dont notice it at all when the revs increase.

Oh, I have a megatune log available if someone can try and load it -I cant seem to open it in MS Tweak for some reason. I'll upload it tonight.

Cheers,

Posted: Mon Jan 31, 2005 1:51 pm
by P.Webb
Michael,

Just let me know where the datalog is. Or you can email me to me directly. I'll run it through MSLVV.

You should download MSLVV anyway. It's a great tool.

When you datalog, make sure you select 'full'. If you don't none of the companion programs like MSLVV and MST3000 will work.

What MT are you using?

-Peter

P.S. Start at 2.2K for R10 and sneak up to 3.3k if that doesn't help.

Posted: Mon Jan 31, 2005 2:35 pm
by Michael
Hi Peter:
2.2K it will be :)
I'll upload the log or send it to you this evening - thanks for offering to take a look!
I'm using the latest beta version of Megatune. Should I revert to the last stable version? Where is the option you set for "Full logging"? I dont have access to this tool now (at work) but maybe its clear in the MT gui.
I'm still running the NB O2 sensor as I wanted to become familiar with this first before switching to WB.
Cheers,

Posted: Mon Jan 31, 2005 7:45 pm
by P.Webb
MT2.25B is working well for me. I'm using the MSn-E .020i firmware though. The full option went away in 2.20 so disregard the 'full' datalog comments.


Are you running the -E or B&G 2.98 firmware?

I looked at your datalog and as suspected you have some nasty tach spikes. You can tune fine with the NB02 though the WB will be better.

Take another datalog when you get the spikes sorted out. I'd like to see how it's running out of the box so to speak.

-Peter

Posted: Mon Jan 31, 2005 7:48 pm
by P.Webb
BTW, make sure you add yourself to the success stories in this forum and msefi.com.

This is great.

I won't name names but I know there are a couple of forum readers with running cars that aren't on the list here...

<cough><cough>

-Peter

Posted: Mon Jan 31, 2005 11:49 pm
by Michael
I am running the MSnS-Extra Firmware.

Here is a link to the log file in case someone else wants to take a look at it:
http://www.alfagtv6.com/MegaSquirt/data ... 301640.zip

I have the 2.2K R10 installed - I'll test tomorrow.

By the way Peter, were you able to load the log into MS Tweak?

Cheers,

Posted: Tue Feb 01, 2005 12:46 am
by joey
P.Webb wrote:2.2k should be fine for most applications. The warning is for the non-transistorized ignitions that don't have the 400v spikes. If it's reading directly off coil(-) there isn't much to disturb it. This is the scheme for them old points type ignitions.

The L-Jet, and subsequently your MS is getting the tach signal from the Bosch ignition box. The Hall sensor is providing crank angle to the ignition box which turns it out to pin 1 of the L-Jet.

-Peter

thanks peter ! so this wont change anything if my ignition is upgraded to an MSD system further down the track?

mike, let us know how the 2.2kohm goes !

cheers guys,

joe