M274 2.0L difference between 200 & 250

[sillbeers15]

Hi,

 

I did not gain any fruitful return searching the web on the output difference of 184ps/300Nm & 211ps/350Nm. Were these due to ECU program difference alone? Or does it include hardware differences? Anyone care to enlighten me?

 

The M274 @ 1999cc guise does not have high compression ratio as advertised by MB. They're just at 9.81:1, very suitable compression for turbo charging from my experience of turbo charged cars ownership in the past.

 

By tuning the ECU fuel and ignition timing maps and increasing the boost output to 0.8 - 1.0 bar should push the output to a reliable 250ps/400Nm with no need to upsize intercooler, injectors, turbochargers provided the 7G tronic gearbox is up to it (I should think so, as these numbers are nowhere extreme for 2.0l four turbocharged cars).

 

All I need is to get a reliable tuner to rechip the ECU on a dyno. And no going back to agent for servicings,....as the dyno tuned program will be wipped out once the agent performs a SCN coding onto the ECU based on VIN.

 

 

[Odessus]

From my understanding the intercooler is different.

[sillbeers15]

In the basics of Thermal dynamics in 'A' level Physics: (Pressure x Volume)/Temperature = constant

 

So if one were to increase boost with same size intercooler maintained -> temperature of intake air rises. Which is a not good against engine reliability in a forced induction internal combustion engine.

 

This is the reason for increasing intercooler sizing to accommodate boost increase while maintaining intake air temperature. 

 

Fuel is also another agent for taking out heat other than offering its primary function of providing energy. With a well tuned ECU, at loading points (certain rpm range, usually 3500-4000rpm depending on particular engine characteristics) more fuel is ejected from the injectors,...no longer old school of running rich through whole engine rev range.

 

Water injection (utilizing specific latent heat of water to take away heat in combustion chamber) is another useful methodology not well understood by many including myself. With the water injection controller programmed into engine ECU would be a great way to avoid engine detonation. Rolls Royce Marline engines in WWII Sprit fire fighter planes used this technology w/o the sophisticated 32bit electronic engine management found in road cars today.  

[sillbeers15]

Below 1 bar boost is considered mild tune,...there is no need for intercooler upsizing.

[giggss]

so for those using piggyback , need to take note of upgrading of hardware too ?

[sillbeers15]

so for those using piggyback , need to take note of upgrading of hardware too ?

The principle is the same. Only most of the preprogrammed or hard coded solid state circuits are mildly tuned (< 1.0 bar), no need to add hardware.

 

The current MBs running on Communication Area Network or CANbus, we do not have the freedom to run independent ECU such as HKS FCON V-RRO or Motec anymore ( I had an SGD$11,000 FCON V-PRO 3.24 tunned by Garage-R in my previous toy,...but I have out grown that since)

[sillbeers15]

For higher boost than 1.0 bar, hardware restrictions are (in order according to power gain requirements):

1   Intercooler;

2   Exhaust / downpipe / header

3   Intake / AFM (if any)

4   Injectors

5   Turbocharger

6   Pistons