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Members => Projects & Installs => Topic started by: z0tya on October 08, 2009, 02:50:16 PM

Title: BMW E36 m50b25 n/a
Post by: z0tya on October 08, 2009, 02:50:16 PM
engine config:
inline 6 24 valves
bore/stroke: 84/75 mm
comp ratio: 1:10
firing order: 1-5-3-6-2-4
ignition timing 6-12 deg at 700rpm *
fuel pressure: 3.3-3.7 (vacuum off) 2.8-3.2 (vacuum on) *
injector resistance: 15-18 ohm *
iat sensor: 2200-2700 ohm at 20C, 760-910 ohm at 50C *
iac valve: 20-25 ohm between p1-p2, 20-25 ohm between p2-p3 *
clt sensor: 2290-2700 ohm at 20C, 290-364 ohm at 80C *
crank sensor: vr, 400 ohm between p1-p2 *
cam sensor: vr, 800-1200 ohm between p1-p2 *



* from autodata

firmware version: 1.1.27 12x12

primary trigger:
60-2 vr

(http://www.cosworth.hu/misc/bmw/primary.jpg)

sec trigger:
not used

(http://www.cosworth.hu/misc/bmw/secondary.jpg)

reference tooth table:

(http://www.cosworth.hu/misc/bmw/ref_tooth.jpg)

injection:
semi sequential

(http://www.cosworth.hu/misc/bmw/inj_settings.jpg)

inj outputs:
  inj A ch1  (EC36P7)  for 1 cyl
  inj B ch2  (EC36P19) for 2 cyl
  inj C ch4  (EC36P8)  for 3 cyl
  inj D ch8  (EC36P20) for 4 cyl
  inj E ch16 (EC36P9)  for 5 cyl
  inj F ch32 (EC36P18) for 6 cyl

(http://www.cosworth.hu/misc/bmw/inj_outputs.jpg)


ignition:
wastedspark

(http://www.cosworth.hu/misc/bmw/ign_settings.jpg)

ign outputs:
  2 (EC36P34) for 1 & 6 cyl
  3 (EC36P36) for 2 & 5 cyl
  6 (EC36P24) for 3 & 4 cyl

(http://www.cosworth.hu/misc/bmw/ign_outputs.jpg)

IAC controlling:
dual solenoid mode with pwm - trying use stepper A/B (max load 1 A)
with dual solenoid output, there is some restriction with the output selection. The 2 outputs must be neighbors like configure ign/6 and use ign/6 and ign/7 (the latter will be inverted)
Title: Re: BMW E36 m50b25 n/a
Post by: z0tya on October 08, 2009, 03:51:32 PM
I am a bit confused with the inj/ign output...

h[2] is the ignition sequence lookup table going reverse order, last element is looked up first
so the 2:3:6:2:3:6 seems correct

h[0] is the injector lookup table going reverse order, last element -determined config.alternate- is looked up first
firing order: 1-5-3-6-2-4
which means injector sequence: 1-16-4-32-2-8
reversed : 8-2-32-4-16-1
how many times need transversed to get right firing angle?
at first I try twice: 16-1-8-2-32-4

h[1] is the reference tooth table
0-40-20-0-40-20 is good or 0-20-40-0-20-40 is the right values?
Title: Re: BMW E36 m50b25 n/a
Post by: gunni on October 08, 2009, 08:00:48 PM
Are you running the COP´s?
If so you´ll have to setup dual out.

8 2 32 4 16 1

is going to be right for the injector sequence.

Reference tooth table is
0 40 20 0 40 20

But if it´s dual out , I believe it´s
0 40 20
Title: Re: BMW E36 m50b25 n/a
Post by: z0tya on October 08, 2009, 08:22:56 PM
not cop, 6cyl wasted spark coil from edis so no need dual mode
Title: Re: BMW E36 m50b25 n/a
Post by: gunni on October 08, 2009, 09:03:45 PM
Then the ign setup you had was right.
Title: Re: BMW E36 m50b25 n/a
Post by: z0tya on October 09, 2009, 01:34:57 PM
thx!

What is the suggested iat and clt patch?
In a hungarian bmw forum guys say 1900,256.

Need flyback diode paralell the iac coils, or the stepper chip has it?
Title: Re: BMW E36 m50b25 n/a
Post by: gunni on October 09, 2009, 03:33:28 PM
Run the IAC with IGBT´s or FET´s.
And use a diode on it , it should make it very stable.

I´ve always used 2025 or something like that on bmw´s. But you´ll have to verify though.
Title: Re: BMW E36 m50b25 n/a
Post by: z0tya on October 09, 2009, 08:45:33 PM
really need to disconnect water hose to check timing?
(http://www.cosworth.hu/misc/bmw/timing-mark.jpg)

brrrrr:)

Vems has only 4 igbt and I think one fet died....if the stepper can't handle the iac current, i need soldering...
Title: Re: BMW E36 m50b25 n/a
Post by: gunni on October 10, 2009, 12:06:14 AM
It would have been best to order the vems with all igbt´s and fet´s.
As you most likely will always have something to use them for.
Title: Re: BMW E36 m50b25 n/a
Post by: z0tya on October 19, 2009, 04:17:57 PM
I have made a helping draw to understand the trigger setup. Because of the tricky alignment of the trigger wheel, the real first trigger event is not the first cylinder tdc but the 2.nd 5.th pair.
(http://cosworth.hu/misc/bmw/trigger1.png)
(http://cosworth.hu/misc/bmw/trigger2.png)

From 1.1.x version vems uses the h[1] reference tooth array, shows which tooth to trigger from.
The h[1] correlate with h[2], so can be rotated together.

Both of the must read from the end, backward. And can be rotated together.

h[2]   2     6    3    2     6    3
h[1]   0   40   20    0   40   20
similar to:
h[2]   6    3    2     6     3    2
h[1]  40  20    0    40   20    0

where the ign outputs are:
  2 (EC36P34) for 1 & 6 cyl
  3 (EC36P36) for 2 & 5 cyl
  6 (EC36P24) for 3 & 4 cyl

The 2nd version is understandable better, and show how you hold the firing order, when you use the 2&5 cyl tdc to triggering.

(We need more than an hour to understand the working of this table without exact documentation....)
Title: Re: BMW E36 m50b25 n/a
Post by: GintsK on October 19, 2009, 07:15:31 PM
Quote from: z0tya on October 09, 2009, 08:45:33 PM
really need to disconnect water hose to check timing?
(http://www.cosworth.hu/misc/bmw/timing-mark.jpg)

brrrrr:)

Vems has only 4 igbt and I think one fet died....if the stepper can't handle the iac current, i need soldering...
I usually make own mark visible from right underside. Adopt indicator in spark plug hole is more easy than catch OE mark with timing light!

Gints
Title: Re: BMW E36 m50b25 n/a
Post by: SamSpade on October 19, 2009, 10:42:53 PM
Good stuff in this thread. Pls keep 'em coming.
Title: Re: BMW E36 m50b25 n/a
Post by: multiplex on October 20, 2009, 01:19:55 AM
looks like you are going to run in 'wasted spark' mode?  Are you still wiring all six coils to individual outputs?

I see you only called out 3 pins for your outputs.

If you really get stuck, let me know. I have my s52 running full sequential. I know how frustrating it can be

Title: Re: BMW E36 m50b25 n/a
Post by: z0tya on October 20, 2009, 03:06:17 AM
no, i hate those coils:))
I am using good old edis 6 cyl wastedspark coil from ford scorpio cosworth 24v.
it is near bulletproof against the 6 individual coil, and good for more than 2 bar boost in forced imduction.
And I no need the sec trigger with this setup.
Title: Re: BMW E36 m50b25 n/a
Post by: z0tya on October 27, 2009, 07:44:23 PM
Engine stall after open thottle - IAC config problem?

We did the setup for the engine, which start after some tune of afterstart enrichment because of the dense mixture. The idle is acceptable, but we have some problem with the bwm dual solenoid.
This is a half-open valve when unpowered, so when plugged off the rpm goes sky high. So for idle need about 40 value in reftable, and we must enable iac follow tps because withouth this engine often stall after small blip of the throttle.
This is the last setup:

(http://www.cosworth.hu/misc/bmw/idle_settings.jpg)
(http://www.cosworth.hu/misc/bmw/idle_pid.jpg)

After tuned VE table the avability to stall after open throttle remains, so I need some help if anybody has experience with this iac valve.

(http://www.cosworth.hu/misc/bmw/stall1.png)
(http://www.cosworth.hu/misc/bmw/stall2.png)

(I prefered the manual idle set with extra air pipe or with throttle open screw, and vems iac control for crank, warmup and extra load, but this engine stall without idle control)
Title: Re: BMW E36 m50b25 n/a
Post by: GintsK on November 01, 2009, 04:00:08 PM
Quote from: z0tya on October 27, 2009, 07:44:23 PM
Engine stall after open thottle - IAC config problem?

We did the setup for the engine, which start after some tune of afterstart enrichment because of the dense mixture. The idle is acceptable, but we have some problem with the bwm dual solenoid.
This is a half-open valve when unpowered, so when plugged off the rpm goes sky high. So for idle need about 40 value in reftable, and we must enable iac follow tps because withouth this engine often stall after small blip of the throttle.


After tuned VE table the avability to stall after open throttle remains, so I need some help if anybody has experience with this iac valve.


(I prefered the manual idle set with extra air pipe or with throttle open screw, and vems iac control for crank, warmup and extra load, but this engine stall without idle control)

This is strange. Newer saw BMW dual valve with spring inside!
From my experience this type of valve is more predictable than 2-pin ones.

I suggest enable advance aid for idle. And lower P to something about 15-30, put I about 15-20, D ~100.
But first check your valve!

Gints
Title: Re: BMW E36 m50b25 n/a
Post by: z0tya on November 03, 2009, 03:26:38 PM
okay I will try...