Need help setting up 1st time ignition map table

Mad Professor · Post by **Mad Professor** » Sun Mar 12, 2006 4:06 am

This is all the info I can find atm.

woh · Post by **woh** » Sun Mar 12, 2006 9:17 am

Here is my best estimate of what the original ignition curve looked like.

For different rpm values, change line 11 and the others will change as well.

Mad Professor · Post by **Mad Professor** » Sun Mar 12, 2006 11:43 am

Ok thanks I will give that a try in the morning.

With the timing table I have in atm, when the engine is warm the rpm's hunt around alot.

Peter Florance · Post by **Peter Florance** » Sun Mar 12, 2006 2:34 pm

woh wrote:Here is my best estimate of what the original ignition curve looked like.

For different rpm values, change line 11 and the others will change as well.

I really like this table
The 5 degrees static was the key unknown.

Great work, Werner!

woh · Post by **woh** » Mon Mar 13, 2006 4:57 pm

Peter
Thanks

Off topic:

I have just about completed my MGB with megasquirt and looking for something different.

I thought a BMW might be the ticket. Any advice an a late 70's early '80s small BMW. It needs to be fun to drive not overly expensive due to rarity, but reliable and something an amateur mechanic can deal with. I'm thinking a 2000 or 320 ??

woh · Post by **woh** » Mon Mar 13, 2006 5:02 pm

Mad Professor

Try this; Set the four values around the idle rpm of the spark table to 10º Then set the lower rpm (add a 500rpm column if needed) to 25º . This has stabilized the idle for me.

You'll always get some bouncing on the 3 digit idle reading of MT, but the tach should be solid.

Peter Florance · Post by **Peter Florance** » Mon Mar 13, 2006 5:38 pm

woh wrote:Peter
Thanks

Off topic:

I have just about completed my MGB with megasquirt and looking for something different.

I thought a BMW might be the ticket. Any advice an a late 70's early '80s small BMW. It needs to be fun to drive not overly expensive due to rarity, but reliable and something an amateur mechanic can deal with. I'm thinking a 2000 or 320 ??

Agreed on the rpm tuning. I use the 3D tuning map and watch it behave at idle. You can usually watch the cursor running up and down steep parts of the spark advance curve where instabilities occur.

mandatory BMW content:
You can tell by my sig and website what I like.

Actually the e12's feel much smaller than they look. And they have the right combination of modern reliable stuff (79-81) like electronic ignition and ljet (which runs great on that car) but no OBD-anything. Plus the torque of the M30 motor makes everyone smile. I've had my euro since 1984 if that tells you anything. Brake are same calipers as Ferrari 308. Super clean cars are often less than 2000.00
Highway mileage can approach 25mpg if tuned well.

I think 83 320i is Ljet and is pretty sorted out. I had a 77, but it was pretty archiac and the thermo reactors were scary. 2002's are ok but 320i are much quicker and the handling is similar (a little looser in the rear).
The older 320i's are CIS and have the usual issues but can be made to run reasonably well.
Hope that help.

Madprof; please keep give us feedback on how it goes!

woh · Post by **woh** » Mon Mar 13, 2006 5:58 pm

Thanks Peter

Peter Florance · Post by **Peter Florance** » Mon Mar 13, 2006 7:16 pm

Peter Florance wrote: Plus the torque of the M30 motor makes everyone smile.

From the megasquirt meeting dyno day: NA 3.5L m30 motor with 250K miles on it. These motors are friggin unbreakable.

Mad Professor · Post by **Mad Professor** » Mon Mar 13, 2006 11:36 pm

OK I will give it a try as soon as I have a free mo, and my laptop wants to play ball.

I also will try and get a datalog.

Thanks for your help.

mikesb · Post by **mikesb** » Tue Mar 14, 2006 7:57 am

Great thread, very timely for me.

Werner, I used your spreadsheet for figuring out my ignition map too. Just wanted to say thanks!