hally

Over the last few days i have been attempting to dial in my a/f ratio using the Montronic Editor and The Pocket Programmer 2, an EPROM programmer.
Below is a screen shot from the Montronic Editor.
Also below is the a/f charts and full throttle maps from my last 4 iterations of tuning.
Tuning above 4500 was a bit harder than lower down in the RPMs, you can see i only have small differences in this area between versions 6,7 & 8, yet the air fuel ratio i get makes a quantum leap between 11.5 and 12.3ish. I know that the air flow meter is maxed out in this area, maybe that has a lot to do with it.
Speaking of logging, i have been using a beta version (tech edge version 2 compatible) of Jon Burchmores's Palm Pilot software to interface with the Tech Edge. This has been brialliant (Find jon via the www.wbo2.com site), having a PDA in the car instead of a laptop is really practical, it fits easily in the centre console which is handy for reading and also starting and stopping logging. The audiable alarms you can set are handy also, eg to identify a load zone, or a/f range, lets you keep your eyes on the road where they have to be 100% at speed.
I've also edited the part throttle fuel map, to scale it back where it exceeded my dialed in full throttle map values. Was aiming for an a/f of low twelves from 4000 rpms up, ended up a little bit leaner due to 4500+ issues mention previously.
Any feedback, suggestions appreciated, especially from people who have programmed their fuel maps.

Bri Bro

Looks like you are got it dialed in I think I might give this a try after the snow melts!!

NZ951

Could be a little fatter up top to give you some safety, hard to tell if you dont know if you are getting much knock. Have you seen the Link Knock Block? It is an ideal tuning partner to this kind of stuff...

hally

Hi Andrew, yeah i was shooting for 12-12.1 in the upper RPMS, but i get 11.5 when i add a little more fuel like in v7, so i settled on 12.2-12.3. Yeah the knock block sounds handy, though I'm only running 15psi boost which is tailing off toward redline (ala manual boost control) so was thinking that i should be safe below 12.5.
What do u think about running 13 between 2-3K rpms, running a little leaner is suppose to help spoolup right, i have read some of danno's posts where he suggests this. I presume this is safe as i can generate more load on part throttle between 3-4k where the DME is still shooting for 14.7 in closed loop.
Brian, yeah i have been impressed with how smooth this apprach has been, from what i have read i get the feeling that it is easier path then going piggy back, plus better i think due to keeping fuel and timing in sync, and having one less piece of electronics to wire in.

NZ951

Yeah 12.2-12.4 should be ok, I plan on running no leaner than 12 at full boost if possible. running 13 between 2-3K is dependent on whether you have full boost of not. All the A/F's should be in relation to the MAP. So what you really need is MAP or psi levels and an A/F ratio. You may hit full boost (15psi) at or before 3K and have an AF of 13:1. That may not be desirable, again you need to know if you are knocking really.

hosrom_951

Having a leaner mixture at say 2,600-3,000 or so on WOT would help in spool up since the exhaust ports would be running hotter, hotter exhaust gaes and thus spool. But again, you need to see what are the 'other' systems are telling you.........

pk951

How do you know what timing values to enter for any given rpm.

Do you use base chips as a reference, and go from there?

How much was it for the download for Motronic Editor?

Interesting project keep us posted, give us more about the nuts and bolts of programing the chips.

hally

The Montronic Editor is free, download it here:
http://www.mskar.org/dme_download.html
I discovered a small bug in the software relating to the maximum RPM setting, see this thread:
https://rennlist.com/forums/944-turbo-and-turbo-s-forum/176899-eprom-compatibility-question.html
I started with a guru v8 chip as a base (a 15psi chip). You are able to edit the timing maps also, but without a tool such as the Link Knock Block mentioned by NZ951, that would be risky.
I got the pocket programmer 2 (for programming the EPROMS) and a D_ERASE (for erasing EPROMS) from http://www.xtronics.com/memory/EPROM.htm
Ordered a few of these EPROMS
http://www.jdr.com/interact/item.asp?itemno=27C64A-150>
but the ones i actually recieved were 27C64G s which required of programming voltage of 21 volts (a setting on the pocket programmer software, see image below of what the pp2 GUI looks like)
These are working fine for me now.

NZ951

That is pretty sweet Hally... you will do the chip programmers out of business!

hally

Hey do you think it is possible that i have an injector that sticks open when it gets close to its maximum flow rate... The way i get this leap in a/f ratio between 11.5 and 12.3ish with small adjustments to the fuel map just seems a bit suspicious to me. I did a few more 3rd gear pulls yesterday and i got a few little leaps back to 11.5 around 5.4, 5.6K rpms

Ben Z.

Hally-

Maybe this could just be a case of bad resolution from your wideband. From your plot of AFR vs. RPM, it looks like the AFR values reported are only at certain values. If that is the case, it is possible that the leap you are seeing from 11.5 and 12.3 when you switch maps may not be real. Perhaps in the first map the actual ratio is 11.8 which the controller/recorder rounds down to 11.5. Then with the second map the actual ratio is like 12.0 which gets rounded to 12.3. If this were the case, then an actual 0.2 change in AFR might show up as a 0.8 change in your plots. This is just an idea, so I could be way off...

hally

Ben, you've nailed it, thanks. The Palm Pilot is storing the logged data as lambda values to 1 decimal place, ie 1.1 lambda = 11.5 a/f, 1.2 = 12.3.
Edit - actually these aren't lambda values, cause 1.85 = 12.5 a/f from memory, so its just some app specific format for logging the a/f, anyway the resolution problem is highlighted in graph
I'll do a run with the laptop, or see if i can configure PDA to store more precision, the tech edge operates at greater resolution than what PDA is logging.

Heres the data exported to windows and imported into excel..

Bri Bro

Something looks wrong with the lamda values in the graph. Is load=Duty Cycle? If it is, you need bigger injectors.

Lamda=AFR
0.83=12.3 to 1
1=14.7 to 1
1.1= 16.2 to 1

hally

thanks Brian, i just edited above post with similiar thoughts, only you got the lambda - AFR translation right
load is the AFM load where i have configured 5v = 100%

*eurospeed951*

Hally, about the motronic editor. How does it collect data. Does it just read the data off of the EPROM via the chip programmer?