M272 2.5L airbox mods
Thread Starter
MBWorld Fanatic!
Joined: Mar 2007
Posts: 1,518
Likes: 1
From: STL
W203 C230SS
M272 2.5L airbox mods
I was out in my shop this afternoon when I got home from work and I was just poking around the car. I've read of airbox mods for other cars (MB and other brands. I decided to take mine off and see what it looked like on the inside. See if I could find any cheap improvements for flow. I noticed a bunch of tall ribs that ran against the airflow. In my mind taking those off would greatly improve the flow. Especially the ribs just before it heads to the intake/throttle body/MAF area. I don't know why they would be in their in the first place. Possibly to quiet the intake or make the airbox more sturdy? Either way, I took them out via a dremel and a pair of pliers. I also used some thick rubber gasket material I had in order to increase the volume of the airbox a little. It's more or less the same concept as the Renntech box for the other engines- it's pretty much a smoothed out factory box that's slightly taller (more volume). Granted, the Renntech is CF, it's still roughly the same concept.
Was my theory correct? Just curious what everyone else thinks. I know there won't be very much gained, but it sure looked like it couldn't hurt. Before and after pictures.
Was my theory correct? Just curious what everyone else thinks. I know there won't be very much gained, but it sure looked like it couldn't hurt. Before and after pictures.
Last edited by bumpnzx3; Mar 16, 2009 at 10:03 PM.
Senior Member
Joined: Feb 2004
Posts: 252
Likes: 0
From: CT
Did you happen to get a chance to install it and take it out for a spin?
I'm interested to see if the intake got louder, and although I doubt there were any performance gains to be had, it sure would be nice.
I'm interested to see if the intake got louder, and although I doubt there were any performance gains to be had, it sure would be nice.
Thread Starter
MBWorld Fanatic!
Joined: Mar 2007
Posts: 1,518
Likes: 1
From: STL
W203 C230SS
The table in the pictures is actually the top of my bar out in my sunroom/4 season room. It was a work in progress for a little while
I ended up making my own version of the LET intake that's available for the C32/C55. I hollowed out the airbox and used my rubber material I had as a spacer to creat a tad more volume. I then took off the factory snorkles on the front of the car and used some spare 3" tubing I had from my Focus tuning days, along with a couple clamp on universal filters right in front of the intake holes in the radiator support.
I first drove it with the K&N filters I had in there to begin with, hollowed out airbox, and factory snorkles. I didn't notice any difference in performance, but maybe a shade louder under acceleration or free-rev from idle. When I used my home-made franken-intake, it may have spun up faster from around 4.5k to redline. It sure seemed like it did, but then again, the mind seems to experience what it wants to from time to time. The intake also seemed to be a little louder. Overall- I think I will leave it with the hollowed out airbox and my snorkle/filter setup. I looks better, sounds better, and seems like it might be a little faster. Even if it isn't faster, it sure seems like it is.....kinda the same concept behind a SprintBooster
If anyone decides to do something like this- be sure to plug the two 1/4" holes in the bottom of the stock airbox. If not- the engine will be sucking in unfilter air from those two spots.
I ended up making my own version of the LET intake that's available for the C32/C55. I hollowed out the airbox and used my rubber material I had as a spacer to creat a tad more volume. I then took off the factory snorkles on the front of the car and used some spare 3" tubing I had from my Focus tuning days, along with a couple clamp on universal filters right in front of the intake holes in the radiator support.
I first drove it with the K&N filters I had in there to begin with, hollowed out airbox, and factory snorkles. I didn't notice any difference in performance, but maybe a shade louder under acceleration or free-rev from idle. When I used my home-made franken-intake, it may have spun up faster from around 4.5k to redline. It sure seemed like it did, but then again, the mind seems to experience what it wants to from time to time. The intake also seemed to be a little louder. Overall- I think I will leave it with the hollowed out airbox and my snorkle/filter setup. I looks better, sounds better, and seems like it might be a little faster. Even if it isn't faster, it sure seems like it is.....kinda the same concept behind a SprintBooster
If anyone decides to do something like this- be sure to plug the two 1/4" holes in the bottom of the stock airbox. If not- the engine will be sucking in unfilter air from those two spots.
MBWorld Fanatic!
Joined: Nov 2007
Posts: 1,423
Likes: 0
From: Phoenix, AZ
2014 Ghibli S Q4 & 2008 C350
Interesting post. I was just thinking of modifying the airbox on my M272 3.5L to see if there was anything to gain in there.
Could you retrofit an airbox off a 3.0L or 3.5L on to your 2.5L? That is assuming they are in fact larger, are compatible and would fit under the hood...
Could you retrofit an airbox off a 3.0L or 3.5L on to your 2.5L? That is assuming they are in fact larger, are compatible and would fit under the hood...
Trending Topics
Thread Starter
MBWorld Fanatic!
Joined: Mar 2007
Posts: 1,518
Likes: 1
From: STL
W203 C230SS
I asked that same question a while back. A few of the long time members said it wouldn't work because the intake manifold was a lot different. I never really looked into it any further. I am sure you could mod it somehow to get it to work, but then I wonder if it would look hacked together? They also told me that the factory airbox on the M272 was a better design than the older engine.
I just know that the shape of the intake tubes/the bottom section of the airbox not shown in my pictures forces the air to the top of the airbox- right into the ridges that I cut off. Again, not sure if I truely accomplished anything, but it sure seems like I did, so that's good enough for me.
I just know that the shape of the intake tubes/the bottom section of the airbox not shown in my pictures forces the air to the top of the airbox- right into the ridges that I cut off. Again, not sure if I truely accomplished anything, but it sure seems like I did, so that's good enough for me.
MB World Stories
The Best of Mercedes & AMG
7 Craziest Things AMG Gas Ever Built
Verdad Gallardo
New Electric Mercedes-AMG GT 4-Door Coupe Unveiled: 10 Things You Need to Know
Verdad Gallardo
6 Mercedes Models That Did NOT Age Well (But Are Somehow Still Cool)
Verdad Gallardo
Manual Mercedes? 6 Times Sindelfingen Let Drivers Have All The Fun
Verdad Gallardo
Mercedes SLR McLaren 722 S Is Extremely Rare Example Modified by McLaren
Verdad Gallardo
8 Classic Boxy Mercedes Designs That Have Aged Like Fine Wine
Verdad Gallardo
Flawlessly Restored Mercedes 190E Evo II Heads to Auction
Verdad Gallardo
Electric Mercedes C-Class Unveiled: 11 Things You Need to Know
Verdad Gallardo
Mercedes EQS Gets A Major Update: Everything You Need to Know
Verdad Gallardo
Thread Starter
MBWorld Fanatic!
Joined: Mar 2007
Posts: 1,518
Likes: 1
From: STL
W203 C230SS
I still have around six good months left in me.
MBWorld Fanatic!
Joined: Nov 2007
Posts: 1,423
Likes: 0
From: Phoenix, AZ
2014 Ghibli S Q4 & 2008 C350
I asked that same question a while back. A few of the long time members said it wouldn't work because the intake manifold was a lot different. I never really looked into it any further. I am sure you could mod it somehow to get it to work, but then I wonder if it would look hacked together? They also told me that the factory airbox on the M272 was a better design than the older engine.
I just know that the shape of the intake tubes/the bottom section of the airbox not shown in my pictures forces the air to the top of the airbox- right into the ridges that I cut off. Again, not sure if I truely accomplished anything, but it sure seems like I did, so that's good enough for me.
I just know that the shape of the intake tubes/the bottom section of the airbox not shown in my pictures forces the air to the top of the airbox- right into the ridges that I cut off. Again, not sure if I truely accomplished anything, but it sure seems like I did, so that's good enough for me.
Last edited by Krytech; Mar 17, 2009 at 02:58 PM. Reason: Added quote
MBWorld Fanatic!
Joined: Apr 2008
Posts: 3,809
Likes: 4
From: Chino Hills, CA
Mercedes C300 Sport, BMW 745Li, VW Mk6 Golf TDI
hmm, interesting. Logic is sound and you should have better airflow with the ribs removed. Might have to crack mine open and consider this.
Former Vendor of MBWorld
Joined: Sep 2008
Posts: 1,935
Likes: 5
AMG
Yes & yes pretty much, although you don't need that much support really, its not like its supporting alot of weight. It is mainly more so for sound. With K&N airbox panel filters you will get more sound and maybe a bit more airflow.
Junior Member
Joined: Dec 2008
Posts: 18
Likes: 0
From: Sherman Oaks, CA
2007 C230 Sport
Wild thought, but is it possible it is supporting the integrity from vacuum forces (keep it from collapsing in wards with a hot engine)? I mean, it's not like air is being forced into the engine as much as it is being sucked.
Thread Starter
MBWorld Fanatic!
Joined: Mar 2007
Posts: 1,518
Likes: 1
From: STL
W203 C230SS
i'd like to think it's got that much suck, but i kinda doubt it. went i get back from my business trip, i hope to get a little more drive time. i never drive the car, but the weather is great this week- too bad i had to leave last night.
Former Vendor of MBWorld
Joined: Sep 2008
Posts: 1,935
Likes: 5
AMG
Also your physics is backwards... Air is never "sucked" in, its forced in by natural atmospheric forces at roughly 14psi, Air is PUSHED into the cylinders not pulled in.
Super Member
Joined: Jun 2009
Posts: 526
Likes: 2
From: NYC
08 ML CDI
lol, i did the same with my air box few weeks ago, how come i didnt come upon your thread?? weird..anyway, same conclusion, no significant difference.....
...awaiting my new intake parts, will post photos when complete.....this is extreme intake design.....i think i have some kind of theory to solve our intake problem i hope im right
...awaiting my new intake parts, will post photos when complete.....this is extreme intake design.....i think i have some kind of theory to solve our intake problem
i hope im right
