C43 enlarged air-box

[DRBC43AMG]

For those with the M113 engined c43 or 55 you should all be interested. I got my hands on a bigger air-box which arrived here a couple of days ago. This should definitely improve airflow to the engine in comparison to the OE box which is rather restricted and it is not priced at silly money levels.
The air-box will be installed in the next days and I'll be getting my w202 out of hibernation to test this new air-box. Sorry, I don't have access to a dyno to get some before and after figures, but my butt dyno should work.

Here are some photos just after the new air-box was delivered, showing the OE air-box, the modified version and both side by side.

 

[whitenemesis]

Interesting but unless the inlet and outlet ducting has increased cross section won't the air flow be just the same?

 

[Alex]

The size of the box alone doesn't mean anything if the inlet is unchanged. Not to mention that feeding more air into the engine will make it run leaner. Would be interesting to see how you came to the conclusion that the OE box is restricted.

 

[moonloops]

As mentioned before, if there's no pressure loss between the input and output of an air filter when engine is at full throttle, a pointless exercise.

 

[daveenty]

Modified my air intakes recently and went for bigger boxes but, sorry there has to be a "but", I also went with wider inlet and outlet pipes for it as well to force more air into the turbos. This is where the problem lies with the standard "fit over function" with which Mercedes kindly supply us.

Also, once the intake system was on, I had the car mapped again to compensate for the excess of air it's now putting in, which was necessary apparently. I was shown various figures and graphs by the tuner but they went whoosh on me.

In other words, a worthwhile mod if you're going to do the full system, but a box alone will not make a great deal of difference unfortunately. All IMHO of course, though looking at the other posts it seems I'm not alone...

 

[DRBC43AMG]

Why does the Renntech airbox which is bigger than OE makes the engine breath better with a better performance?

 

[moonloops]

Why does the Renntech airbox which is bigger than OE makes the engine breath better with a better performance?

Because at $4000+ anyone who buys one would never admit to wasting their money

To prove any power gains they would need to take the engine out of the car and have it put on a engine dyno in lab conditions.

 

[DRBC43AMG]

$4000 is silly money, so cheaper solutions exist.

 

[DRBC43AMG]

Here's the installed product

 

[Auto-mobile]

The size of the box alone doesn't mean anything if the inlet is unchanged. Not to mention that feeding more air into the engine will make it run leaner. Would be interesting to see how you came to the conclusion that the OE box is restricted.

The Ecu will self adapt to the extra air, I als think that this will bring down inlet temps a touch.

 

[Bellow]

I als think that this will bring down inlet temps a touch.

Unlikely. Larger surface area of box to absorb engine bay heat. and slowed airflow through it giving more time for the air to absorb that heat.

 

[KeithJG]

Agree the ECU will compensate for the extra air being drawn/pushed in the engine, but only to a limit which may be quite a high one.

Usually ECU remaps are only a must when changing turbos apart from when one needs extra woomf as standard.

There is more air held in reserve in the larger airbox/plenum which the turbo can draw more air on easier especially when the boost is raised even designs of airboxs readily give more power so why not the OP`s larger one!

May not work on an N/A motor but we are talking turbo, the volume of air has to be obtainable and on demand.

Air is not forced into a turbo the turbo grabs what air it can or what is available when it wants it.

The whole thing depends on how efficient the standard airbox is?

As there are larger ones available.....there is your answer.





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[DRBC43AMG]

The Ecu will self adapt to the extra air, I also think that this will bring down inlet temps a touch.

I will also be covering the underside of the box with some nice Thermo-Tec Gold heat barrier to help insulate the air-box from engine soak from under. I'm sure every bit will help.
My son is an engineer specialized in fluid dynamics and will be working out the quantity of air flowing between the both old and enlarged air-boxes. That should be interesting...

 

[Alex]

The Ecu will self adapt to the extra air, I als think that this will bring down inlet temps a touch.

The ECU will need recalibration for anything other than the fractional amount it can compensate for. Not a problem for OP as he is not supplying any extra air to the system, just enlarging some part of it whilst keeping the in- and outlet the same size. As suggested above, this will likely result in larger surface area being exposed to engine heat and won't reduce the IATs.

 

[KeithJG]

ECU`s are very adaptive and can adapt to quite a considerable amount to safeguard the engine for damage in an emergency such as vacuum pipes coming off etc. which will weaken the mixture.

As an example on the Volvo V40 T4 the ECU will compensate from 11psi to 19psi boost pressure and the AFR`s are just in the comfort zone.

On the Volvo T5 it will compensate from 10psi to around 22psi of boost pressure these are petrol motors and i don`t think Mercedes would be any different engine safety wise.

Of course all figures are available for AFR`s on the dyno readout.

 

[whitenemesis]

Merc's quickly go into Limp mode should such an fault occur, limiting power/revs

 

[KeithJG]

Merc's quickly go into Limp mode should such an fault occur, limiting power/revs

I understand that one. So that is their safety valve so to speak?

 

[noogieman]

I will also be covering the underside of the box with some nice Thermo-Tec Gold heat barrier to help insulate the air-box from engine soak from under. I'm sure every bit will help.
My son is an engineer specialized in fluid dynamics and will be working out the quantity of air flowing between the both old and enlarged air-boxes. That should be interesting...

i hope you get good numbers from the test result when you and Junior are done.
i was thinking of buying the same box unfortunatelly seller didn't want to ship outside USA anymore.
i just might have saved a lot of cash not buying this modded box reading the other comments in this thread?