MembersPage/MattiasSandgren/PeppesBmw (2006-07-19 12:48:25)

BMW E30 323 with M20B25 Turbo

peppe_e30_turbo.jpg

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The engine

The turbo system

The config and tables will be updated on this page, and documented properly given some free time. Here they are: [config.txt] and [tables.txt]

Bear in mind that fuel has not been set properly, including afterstart and other enrichments.


Update 2006-07-19

Sometimes when looking for something you are blinded by not double-checking what worked before. It seems something crawled up and died inside the inlet of the intercooler. :-)

I never thought to look at the MAP gauge in MegaTune before - last night I noticed straight away that something was wrong. It never showed more than 80 kPa while free revving the engine - it should be close to 100 kPa (atmosphere). We removed the pressure pipe from the inlet of the throttle body and the engine transformed, it really woke up (night and day) when we removed this restriction.

I'll be back tomorrow with a tuning update.


Changes from 2005

Ignition coils

Above 6000 rpm and some boost this engine ran into a problem with the ignition dwell. The Ford EDIS coils need 4 ms dwell but that was simply not possible since the method used in firmware at the time did not make it possible to use overlapping dwell. At 7000 rpm one revolution of the engine takes 8.57 ms and there are three ignition events. The time between each ignition event is 2.86 ms on a 6 cyl engine, and there is currently 400 us "coil off time" which means an effective 2.46 ms dwell on coils that need 4 ms. The problem would be more serious on a 8 cylinder engine.

The coil dwell limitation had not been resolved by spring 2006 when the car was on the road again. The [high power ignition coils] from Swedish company "Biltema" were chosen and driven in "dual out" mode, which means wasted spark. This has worked well, we have not found their limit yet.

Injector FETs

We have established that poor quality fuse holders caused 2 injector drivers to break. These holders were replaced with more reliable holders with spade connectors that attach directly to the fuse.

I have replaced the damaged FETs, unfortunately the P259 was also damaged and removed, testing on the engine shows the board to be healthy again.

Injector Flyback

The GenBoard/Manual/PowerFlyback has been installed and made a tremendous difference with the injectors. We have found a setting for the injector characteristics that work, more tuning will probably change this but it runs well at idle and the map seems properly flat and uninteresting in this area.\n

injopen = 0
injocfuel = 400 usec


Extra pins

No stepper motor chip in place, leaves many EC18 pins free for use.

EC18-5Ground for SCL and SDA
EC18-10SDA (PD1) - on JP1 connector (current default for AntiLagSystem)
EC18-11SCL (PD0) - on JP1 connector (current default for shift cut)

Q: How to enable shiftcut? Through grounding of MCP3208 pin 7?

I can't find a good reference information on this. I will update Wiki accordingly if the answer is given here.