Running to rich on m30b34

Discussion pertaining to positive pressure E28s.
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Sabershark
Posts: 12
Joined: Jun 20, 2017 5:01 PM
Location: Marysvill

Running to rich on m30b34

Post by Sabershark »

Have a problem figuring in out running to rich
M30b34 motor motronic 1.1
Turbocharger ,
42lb injectors
255lp Walbro in tank single pump
Turbi chip
Fuel pressurw regulator set at 40psi before idle
Air fuel ratio reading 14.7 at 20psi of fuel if adjusted
Air fuel ratio reading above 17.0 at fuel psi set at 40

Car has afm not maf

Car has had FMU and worked choking at idle but great at 4000 rpm
I disconnected FMU and motor runs smooth at 20psi of fuel
As soon as Increase fuel psi to 40 it runs too rich. Too much black smoke out of exhaust

Please criticism is acceptable here tell me what I need
All I want is to gain 50hp not much
My friend said I need either miller set up $1300
OR convert to megasquirt-$1400
OR cheaperversion purchase a begi 2025 fmu

Your suggestions
Oh and the boost gauge reading 25vacuum.
And when I accelerate it goes to 0 but not to boost level
tschultz
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Joined: Mar 01, 2009 7:58 PM
Location: Denver, Colorado
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Re: Running to rich on m30b34

Post by tschultz »

Do you have a wideband?
How are you controlling fuel. What ratio is the FMU?

People already tried to help you over on bigcoupe...


Why are you running 42# injectors on motronic? That's probably part of your problem right there... You should be closer to 24 or 30 lb injectors with Motronic. Just use the stock FPR and BEGI 2025.
Sabershark
Posts: 12
Joined: Jun 20, 2017 5:01 PM
Location: Marysvill

Re: Running to rich on m30b34

Post by Sabershark »

The miller recommend 42lb injectors.
The fmu is 8.1
the pressure regulator is adjustable so I can controld the pressure but I lack the knowledge on how to make it leaner or proper. So you saying begi 2025 will help with alot of rich combustion
Yes I have wideband
marc79euro645
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Joined: Dec 08, 2008 11:33 PM

Re: Running to rich on m30b34

Post by marc79euro645 »

You can also adjust afm spring tension to adjust rich or lean.
Sabershark
Posts: 12
Joined: Jun 20, 2017 5:01 PM
Location: Marysvill

Re: Running to rich on m30b34

Post by Sabershark »

marc79euro645 wrote:You can also adjust afm spring tension to adjust rich or lean.
How? I heard about it but some told me don't touch it. You'll brake it. How many turns and wich way counter clock wise or clock wise
T_C_D
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Re: Running to rich on m30b34

Post by T_C_D »

Miller is wrong. 42lb injectors way too big for your controls. Install 24lbers.
marc79euro645
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Joined: Dec 08, 2008 11:33 PM

Re: Running to rich on m30b34

Post by marc79euro645 »

I for get which way is which , but a few clicks is all you need. Remove the top cover, open afm door with your finger and watch the spiral spring, you'll see which way to go. More tension = leaner, less tension = richer, but as Todd said you need the right injectors and fuel pressure.
good luck
Sabershark
Posts: 12
Joined: Jun 20, 2017 5:01 PM
Location: Marysvill

Re: Running to rich on m30b34

Post by Sabershark »

T_C_D wrote:Miller is wrong. 42lb injectors way too big for your controls. Install 24lbers.
I installed 30lb bmw e24 injectors with our fmu
At 40psi runs great.
Now lowering psi dose it effect fuel air ratio?
Running at 36 psi I like it
But still want to tune it in for perfect. Learning everyou daye something new
tschultz
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Joined: Mar 01, 2009 7:58 PM
Location: Denver, Colorado
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Re: Running to rich on m30b34

Post by tschultz »

Sabershark wrote:
T_C_D wrote:Miller is wrong. 42lb injectors way too big for your controls. Install 24lbers.
I installed 30lb bmw e24 injectors with our fmu
At 40psi runs great.
Now lowering psi dose it effect fuel air ratio?
Running at 36 psi I like it
But still want to tune it in for perfect. Learning everyou daye something new

Yes, if you try a different FPR (like 2.5bar) you can slightly adjust mixture on the low side. Then bump up the RRFPR to get the fuel where you want in the higher range.
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