MBfinatic

Just did a mod to my C350 and loved it! Just thought I would pass it on to everyone! The top end pulls so much harder!

I upgraded the intake manifold and throttle body from the 272.969 motor (slk 350 09-11).

The parts!


The intake manifold,


Throttle body, You will also need an elbow to mount it all together.


The install,

Remove the airbox and ecu.


unplug these connectors.


undo fuel pressure valve


The valley!


There are more in between steps I just didnt take pictures. Overall great mod and recommend it to anyone trying to make more power out of their m272!

Thaa kiid Jlee

is this mod only for the 350 or it works for the 300 as well

MBfinatic

This would work for the C300 as well. The gains will not be as high but it will still work.

Thaa kiid Jlee

how much did this all cost you

MBfinatic

The intake manifold was about $240 (brand new with gaskets). The elbow was about $40 brand new. Than the expensive part is to find a throttle body. I would recommend buying one used. I paid $450 for my throttle body. They can be bought from around $400-500.

C300Sport

What did you do with the ECU to account for the different setup?

MBfinatic

So far I havent had the ecu changed at all. There are no codes for it. I have been driving it like this for some time. The ecu slowly adapts to it somewhat. My tuner already has the files ready (has done this before to other cars). It runs fine now but of course with a tune it will run better.

hitokiri89

Any idea what your gains are ?

MBfinatic

Not yet. I will be taking it to the dyno again after the re flash and I fix my master cylinder

Stock I put down 232whp and with the cat removal I did 235whp. Im hoping to at least hit 260whp if not more .

jimmythegreek

I have read the slk 350 makes more stock HP than the new style C350s. I see in your sig that u have an 06, they are exactly the same? I thought I read somewhere that there were some basic changes, Im wondering is it a straight R&R to a w204 too?

MBfinatic

Yes my engine is the same M272.960 A straight R&R?

Quoted from Cale himself.. (Another 06 C350 6spd owner)
"Using the 09-11 SLK350 w/ M014 upgraded engine performance pkg (with the "red stripe" on the engine cover) as a muse, I've been in the process of upgrading several key components of my 3.5L engine designation 272.960 to the upgraded fare in the engine designation 272.969 found in that particular SLK350.

Ratings:
"c350" aka 272.960:
approx 270 hp @ 6500rpm

slk350 aka 272.960
approx 300hp @ 7200rpm"

Here is a picture from Cale that shows the stock manifold and the manifold used on the SLK 350

MBfinatic

Has anyone decided to do this mod?

hitokiri89

I'll probably do the throttle body , hard to say ill commit to the intake when the stock intake is so good . Also I don't know if it drops right in on the w204 chassis .

MBfinatic

It will work just fine. Also you cant just do the throttle body, You have to use all these parts together. Im hoping to be hitting around 260whp with the tune. Why wouldnt it fit on the w204?? The is to the engine?

hitokiri89

Idk , I guess because no one has done it on the w204 yet . When you hitting the dyno ? I'm not against being the first guy to do it but I have a lot mods coming up so it wouldnt be for a few months . Why can't I just do the throttle body ?

MBfinatic

Well you can be the first! Its the same motor! If you need help your free to pm me. I should be hitting the dyno shortly after I move (have a lot of stuff to do). Well because the inlet to the intake manifold is a different size. What other mods are you doing? This is a great mod for top end performance!

hitokiri89

New wheels coming in so I need tires , throwing stock mufflers back in for back pressure , Akebono brake pads , new grill , gonnd do suvneer's 63 style bumper , need to buy tips for stock mufflers , smoking head lights and fogs , hid conversion for fogs , full exterior and interior led swap . Powdercoat the new wheels , and sway bars . A lot of stuff lol . Also I got my new tune coming up too .

MBfinatic

Sounds like you have a lot to do. I cant wait to get back on track with the mods.

RedStripe

A w204 c350 owner over at MBJunkies already has done the intake manifold conversion.

Regardless of the chassis, an m272 is an m272. Specifically in regards to this swap, it's a viable option for ANY chassis.

The 09-11 SLK300 also has this setup, but all of the SLKs also have 3.23 final gear ratios, allowing for loss in low-end torque due to tumble flap deletion. Unless the 3.0L owner plans on following up with the 272.969 cams & valvetrain, I would stay away from this mod as a c300 owner. The c350 still has poor gearing (I corrected this the best that I could with a gear swap from the stock 2.82 to 3.07), but it has enough extra power, that after a tune - the loss in low-end is tolerable considering the incredible gain in the upper RPM.

It has been documented (Karo) that with the appropriate tune for the manifold/TB from OE Tuning (& OE only, Jeremy has dyno-tuned this mod personally), that 30 extra hp can be had, peaking somewhere near redline.

MBfinatic

Im excited to get my tune!

jimmythegreek

I was looking at throttle bodies the other day and it seems that the same one is used in alot of the MB cars, the part # cross references many platforms and engines. Is the one listed in this thread a specific one to a performance package on the SLK? I can get these parts pretty cheap Im just wondering if its worth the trouble

MBfinatic

If you have the 3.5 than I would do it. Like he said its not worth it on the smaller motors. I would do it again on a C350 no doubt.

rb23lb

damn jimmy the greek let me know if you do this mod.... I trust your judgement after reading all your posts so if you have success I think I am going to buy these parts as well

will be the first certified 30hp mod for the w204 c350 yet!

MBfinatic

I will be posting a dynograph soon.

until the end

Keep us updated i think ill do it 2