xupd26jor

I have a 1994 c220 , i just install a custom made turbo kit with a fifth injector but i don't like it , i need to know what kind of bigger injectors i need to install to finish the tunning and performe a dyno test to see how much whp this engine can build , please somebody help me to figure out thanks and happy new year. https://mbworld.org/forums/members/x...17-08-0937.jpg

whipplem104

It depends on how much hp you are trying to make. What kind of fuel management are you using?

RBYCC

Where is the fifth injector located and how are you controlling it ?

xupd26jor

the spray injector is located 3 " before the trottle body and I use a nos solenoid whos is activated with a air pressure switch set up to open at 6psi of boost

ohlord

Horsepower.

RBYCC

Purchase a Split Second additional injector controller to fire the fifth injector.
It is a stand alone with an internal MAP sensor.
Costs about $350...

Your stock engine/fuel management remains untouched, so you probably don't need larger injectors.
Just need to properly control the fifth injector !
This way no problem passing emissions test and idle and low speed is per stock spec.

The Split Second is programmed via a laptop and is 3D mappable.
Best to do the tune under load on a dyno and try to maintain about .85 lambda / 12.5 afr under boost.

After you set it up do some hard driving and then pull your plugs.
Important to see if the location of the fifth injector is correct and you are seeing a fairly even distribution of the enrichment under boost.

Ed a.

NitrogenBalance

Do you think this would be a better means of fueling my setup as well? I'm currently using the split second MAF clamp on the stock fuel system at 4.98V. Fuel pressure is a rising rate boost referenced FMU from vortech. My fuel pressure idles around 55psi and gets about 85ish psi under boost. There is a slight lag with fuel pressure, nothing scary, but nothing smooth either. A/F is good with the H20/meth dropping it slightly richer under load. I know very little about tuning and what can be done but I know that there is nothing smooth, efficient, or specific about my tunning/fueling setup. If there was a very nice way to incorporate 1 or maybe several smaller injectors to run off this other splitsecond unit would you think it would be better?

I'm sure that any type of fine tuning would help wonders with my car.

RBYCC

I'm not a big fan of rising rate devices as they can't be tied directly to maintaining a desired enrichment AFR.

The only real way of mapping is through a stand alone or piggy back control that directly fires the injectors based on feedback from a MAP sensor and engine RPM.

You need to do the settings on a dyno with the AFR measurement taken from a wide band O2 sensor.

I like additional injectors provoding you can get an even distribution to all cylinders.
Works great on a street car, maintains stock settings and emission output.
In essence two engines, one stock and the other forced.
The stock engine control is not altered with the enrichment set by the additional injector control.

Without a dyno you really can't get the correct enrichment on any FI engine