Firstfives.org

Hello,

Situation:
535i, Euro, 218hp, M30b34, Motronic 1.0 CR 10:1

Changed from Motronic 1.0 (061 ECU) to Motronic 1.3 (179 ECU)

Motronic 1.3 is from an e32, M30b35 with CR 9:1.

Issue:
Using ECU from B35 with CR 9:1 to B34 with CR 10:1, lost some torque/power, pinging at low RPM under load etc. due to CR difference.

Changed/retarded the ignition timing by 5 degree in Low and High load Maps.
It's better, but not perfect.

Questions:
1. Increasing CR by 1 unit, how much do I need to retard the ignition? how many degrees?
2. Should it be changed only in Low and High Load maps?

Thanks in advance for any help.

What octane gas are you using?

Are you re-programming your 179 ECU chip?

I'm using 98 RON now with 179 and before with 061.

I'm not changing the original files, just copied them to a new EEPROM chip to play with them, not affecting the original chip.

Just downloaded TunerPro, it's much easier to see all maps.

Filled with 100 Ron /Premium petrol
it's an improvement.

This suggest that timing is the issue.

I put a ...179 and a B35 head on my Euro b34 motor and it runs great, but I bumped the CR up to 10:1 so I never had any problems with it...
Now I want to convert to Megasquirt which I just bought but I'm looking for someone who will help me with some fuel and ignition maps for my Frankenstein motor, to get me started a little better than the startup maps that they give you...

If you'll use Megasquirt, to have performance, just replace VAF with MAF or even MAP, individual ignitions.

What Airflow meter are You using?

With stoc 179 chip, even idle are at 950-1200 rpms

With the Megasquirt I won't have to use any AFM anymore because it has a MAP sensor built into the ECU. Full circle. My original 3.0CSi also worked with manifold pressure...
But I'll be able to program the whole thing whether I increase the CCs to 3800 or whatever... I just would like to speak to someone who has already done it. Do you know of any threads or web-sites that talk a lot about Megasquirt and BMWs? I thought I once saw a lot of discussion here on this board, but I can't find the thread...

unfortunately I don't know anybody who understand well MS.

But it should be lot on info on the web and on forums
also some maps which can be used as a starting point.

Solved!
bought a chip from Conny (Coneus) from Germany, he has good reputation on Germans forums.

Now the engine is sow nice!!!
acceleration from idle to ~6700 rmp, no hesitation, uniform, less noise.

more torque at low and middle RPM

Now she like 100 RON fuel