W124 TWIN TURBO MBC INSTALL - PeachParts Mercedes-Benz Forum

RBYCC · #1 03-15-2009, 07:42 AM

I would highly recommend the installation of a manual boost control on any Turbotechnics or Mosselmann twin turbo M103 or M104 setup.

Not even considering the ability to incrementally increase boost, but more for the fact that it synchronizes the independent turbos.

I used a Hallman Pro RX primarily for it's design and light spring which allows fine tuning of boost adjustment.
The turbos spool up faster and by using the boost/control signal from the rear turbo only to open the wastegates gives identical performance to both turbos.

You must first install a boost gauge.
After installation of the MBC adjusted fully counter clockwise ( no increase over wastegate adjuster arm setting), I confirmed via a road test my set 7psi +/- mechanical setting.

What I noticed is that the boost is held at this level without dropping due to the inaccurate mechanical settings.

Haven't been able to road test a half turn increase as it started to rain.

Trying to get dyno time and 1/4 results in the next week or two.

Ed A.

JayRash · #2 03-15-2009, 07:59 AM

gr8 man, i always knew an mbc will make our cars run alot better, especially the spool time.

can't wait to read ur comments when you up the boost, i want my car back now so bad

RBYCC · #3 03-15-2009, 02:26 PM

Quote:

Originally Posted by JayRash

gr8 man, i always knew an mbc will make our cars run alot better, especially the spool time.

can't wait to read ur comments when you up the boost, i want my car back now so bad

I started thinking about it after staring at my boost curve from the January dyno pulls...

The curve was rather choppy...which translated into one of the turbos reaching boost before the other...
Even watching my boost gauge I would see the pressure drop, especially at constant pedal pressure.

Now it holds very strong and the spool up is much faster...

All the installs of TT and Mossellman worked great in the day, but so much out there to make much more power.

Thinking also of a dual purpose of the additional injectors located above the throttle body...
Enriches as designed but the spray mist is more then likely giving a cooling charge to the incoming boosted air from the intercooler ?

CIS-E not too bad !!!

JayRash · #4 03-15-2009, 02:34 PM

yup Ed. The stock injectors located just before the intake valve are said to cool the charge by 20c deg

So ur 2 injectors located up the stream are sure doing a better cooling job.
I like the cis-e such sturdy system.

Joreto · #5 12-05-2009, 02:27 PM

Bit of an old thread but ... Ed do you see any boost spikes with the MBC ? Searching through the net I see that it's very common to see a boost spike after the install of a mbc i.e. if boost is set to 8 psi then it'll spike to say 10 psi before holding the set 8 psi .

RBYCC · #6 12-07-2009, 10:25 AM

Quote:

Originally Posted by Joreto

Bit of an old thread but ... Ed do you see any boost spikes with the MBC ? Searching through the net I see that it's very common to see a boost spike after the install of a mbc i.e. if boost is set to 8 psi then it'll spike to say 10 psi before holding the set 8 psi .

None at all !!!

It's very linear as it was prior to the MBC install.

In fact without the MBC I would get a "flutter" as the individual turbo wastegates opened at different times.

Now the wastegate opening is synchronized as both turbos hold the same boost level until the MBC signals to open.

Ed A.