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View Full Version : C43 & V8 Airbox Suck, Poorly Designed



speedybenz
07-09-2003, 03:55 PM
I am coming to the conclusion that the engine mounted airbox is not just bad, but really bad.

It sits on top of the engine soaking up heat and the volume is very small which is not what you want for your engine.

I would guess the engine losses 6-10Hp from the lack of volume and torturous path the air must travel to exit the airbox.

Can someone look up the part numbers for the air snorkel that connects to the manifold nad comes out and around the side, like what Kleemann uses on thier supercharger stuff.

A larger smooth tube with an airbox like J Irwins with the air inlet coming off the fog light might be the Hp ticket.

However the sytem must be airtight from the pickup at the foglight to the manifold.

Jeff

J Irwan
07-09-2003, 04:11 PM
Originally posted by speedybenz
I am coming to the conclusion that the engine mounted airbox is not just bad, but really bad.

It sits on top of the engine soaking up heat and the volume is very small which is not what you want for your engine.

I would guess the engine losses 6-10Hp from the lack of volume and torturous path the air must travel to exit the airbox.

Can someone look up the part numbers for the air snorkel that connects to the manifold nad comes out and around the side, like what Kleemann uses on thier supercharger stuff.

A larger smooth tube with an airbox like J Irwins with the air inlet coming off the fog light might be the Hp ticket.

However the sytem must be airtight from the pickup at the foglight to the manifold.

Jeff



tell me about it
I've been complain about it since the I4-I6 engine airbox design..
They are routed on top of the valve cover then goes down next to the exhaust manifold...
In addition to that the airbox tunnel is not really free-flowing since it has so many sharp corners ..

No wonder in generall W202 vs E36 3 series is more inferior in term of the engine breathing , throttle response and the performance.. ;)

I don't undersatnd Why mercedes so stupid, why they didn't put the airbox on the driver side, away from the exhaust manifold..

(no wonder they have a lot more avaliable intake for BMW 3 series E36 in particular. The airbox is on the driver side and the exhaust manifold on the other side) so at least the intake won't suck up the heat directly...


Jeff, about putting up with the heat, you could try to put a heat-refelctive tape under the airbox..on you4 C43 (this also applies to other V8 engine).

I read somewhre at Mercedesshop forum that you could benefit 2-4 hp you lose from the heat (this topic recently has been brought up again at mbworld.org as well.)

PS: even my intake canister will get hot sometimes... the good thing about my intake is the air pass through really quick so the air temperatures inside didn't increase that much..higher at all..
I didn't measure the temp outside vs inside the canister, but I Can't tell you this even when it was 98 F outside I still don't have the lag feeling when mashing on the accelerator :p)



Regardz,


J Irwan

CKlasse
07-09-2003, 07:37 PM
woohoooo... another project! :)

Denlasoul
07-09-2003, 07:51 PM
I ordered some heat shielding for the underside of my airbox. Hopefully, it will bring down the temps a bit.

BenzoAMGpower
07-09-2003, 08:34 PM
Denlasoul......where did you order this heat sheilding?

Denlasoul
07-09-2003, 08:49 PM
I cant remember from which dealer, but I got it form this site:Heat Shielding (http://www.thermotec.com)

kodiak
07-10-2003, 09:54 AM
J Irwan -- You have got to release the design and specs for that intake. There are just too many of us with I6 engines that suffer from intake heat soak. Have some pitty! :D

~dnm

KurumaGOD
07-14-2003, 01:49 AM
TRUE! J Irwan...share wit us man! :D

5.52
07-16-2003, 08:27 AM
Snake Oil for Sale! HP increases to your hearts content!

...seems to be quite a bit of speculation here

dynos & testing in different ambient temps/ stop and go vs, highway & testing air flow rates/ air turbulence rates & air/fuel %'s will hold the truth (serious tuned cars do it all the time):

even if MB airboxes suck...do you really think they suck so bad that it would be easy to gain 2-4hp?? and what's 2-4 hp at the crank do?....hardly nothing at the rear end

... be better off taking a performance driving course and deleting all the heavy stuffs from the car vs. chasing reduced heat soak merely in the intake tube and airbox...perhaps even a rear end re-gearing if your after 0-60mph performance

after all, once you get moving (forward) the issue of heat soak becomes moot

also keep in mind that- - that metal tape mod or metal sheet mod used below the air box to prevent heat soak....it also absorbs heat and takes extra time to cool once the car is moving

keep in mind that many tuners find MB airbox volume adequate for stage 1 and stage 2 mods and that if you're going to play with this minor piece to increase performance you'll still be limited by the software, throttle capacity, fuel capacity/ mapping, exhaust capacity, cam, timing, crappy fuel etc.

I'd be sure to do business with a professional R&D tuner w/ Dyno proof before wasting time on chasing what may turn out to be empty promises

There's plenty of unsubstantiated hype re: performance tuning and many folks gullable and ready to take one's word/ spend $ vs. seeing actual proof with guaranted results....Anyone try the Tornado? At least there appears to be dyno's available for those...:bandit:

Sorry to sound like a bummer....just thought I'd interject a little reality into the conversation

5.52
MB are luxo heavy beasts
5.52

speedybenz
07-16-2003, 09:08 AM
5.52,

Much of what you said is true. However I have it on good authority that the airbox is costing around 10Hp.

Your right it is still only 10Hp.

But you are missing the point of what most of us like to do. We like to Tinker with our cars. Some if not all of the mods may make little difference, but sometimes they can make a pretty big difference in drivability and engine response.

As far as driving classes, many here have gone to driving classes and track days.

If you are into making small DIY mods to your car this board is a great place to share your ideas, good and bad. It is a great hobby that gets me off my butt and sometimes the changes make a very large change to the drivability of my car.

My phenolic spacers between the intake manifold and cylinder head is one example.

No one is trying to sell anything, certainly not snake oil. So leave your car stock and enjoy. More power to you.

Jeff

Renn 208
07-16-2003, 01:20 PM
Big Daddy...you should check out the man's ride, and his driving skills. They are both a sight to behold. And while Jeff does post about little power tweaks here and there, I'd be willing to bet that he's made the greatest gains off of his suspension tuning.

And I for one would like to see an MB...any MB hit 1:30 at willow. That would put pretty much all of the aftermarket tuners to shame, esp. since I've seen big buckaroos spent on modded MBs yet none break 1:35. Definitely not an appropriate goal for every MB owner...but if there's anyone out there to do it, it would be Jeff.

Here are my candidates for fastest MB around willow:

Sleestack and his 6.2L 600+ HP CLK Kleemann monster $$$$$$$$
and
Speedybenz.

possible third place of Vadim and his C32....gunning for 400+HP but it's gonna take lots more than that to do it


Just imagine the ramifications if Jeff can pull it off without spending $200K+ to get there.

714guy
07-16-2003, 01:39 PM
Originally posted by Renn 208

. . .

Sleestack and his 6.2L 600+ HP CLK Kleemann monster $$$$$$$$

. . .

Just imagine the ramifications if Jeff can pull it off without spending $200K+ to get there.

:eek: :eek: Was that what that Sleestack guy droped into his car.:eek: :eek: :eek: He's probably got a money tree farm huh??

5.52
07-16-2003, 02:06 PM
Jeff- - Eaaaassy snapper! No need to tell me what to do mister: ("...so leave your car stock and enjoy. More power to you")

please re-read the main point brought up in my previous post: 'Speculation and not proof'

My post has nothing to do about keeping a car stock and/or enjoying their ride in whatever state they decide to own it. It's a free country for gosh sakes and you can do whatever you like to make your car yours

However, the points expressed is but one opinion be it a most sensible perspective (re: claimed perf mods)
at the end of the day- whatever floats your boat and makes you happy is cool... I'm not downing tinkering at all

To reiterate- I call it as I see it: No proof = pure speculation and/or 3rd party heresay....

If one chooses to use a butt dyno, tinkers jus to tinker, or jus cares little about clinical/ disciplined / balanced performance upgrades....well to each his/ her own, we don't live in a perfect world

re: performance driver education- my senses beg to differ..."many" have NOT attended perf driving school and practiced on the track days... and in the very least many don't even have 20 hours of unrestricted track time ...further, many folks cars will not even pass a competent tech inspection to let them on the track

speaking of the track....most serious perf enthusiasts use the same performance barometer in evaluating or recognizing which mod is "snake oil" vs. 'style' vs. "perf upgrade" (cold hard test=proof)

I agree that this is a good place to share ideas- good and bad ---so I'm confident you'll appreciate the ideas I have shared
;)


5.52
kumbaya

5.52
07-16-2003, 02:42 PM
Renn - I'll take your word re: a sight to behold and chasing the magic 1:30 and Willow

My post is not to put down Jeff, his ride, suspension tuning, or driving...or even tweaking here and there

Understand that it's provided as a perspective toward a reality check (re: mods- speculation vs. proof )

5.52
:cool:

speedybenz
07-16-2003, 04:09 PM
5.52,

Link to old Racebike Article in Sportbike Magazine: http://www.fzrarchives.com/fzr/articals/fzr400_600.html

Just a little background info. I raced AMA, AFM and WSMC events on my two Suzuki 750 Superbikes from 1997-2000 and before that many other bikes from a 1992-1997. In the early years of racing I built so many engines I cant count them. But I still build engines for young guys who look to be fast learners. My last AMA spec 600cc motor made 118Hp on race gas, as tested on a DYNOJET dyno.

I had a full on team with a mechanic's and support from local dealers, Suzuki (bike and parts), Arai helmets, Kerker exhaust pipes, Bates Leathers, Dunlops tires and others.

I worked for Dunlop tires as a test/developement rider, with most of the testing done at Willow Springs. My best time there was 1min 22 sec. I was the AFM Superbike Champion for 1998 and 1999 with 10 consecutive wins at Willow Springs, Buttonwillow, Sear Pt and Thunderhill where I still hold the official lap record.

Our team dyno testing everything with our in-house dyno. Oil, exhaust pipes, ECU boxs to alter ignition timing and the fuel curves, Cam timing. Cylinder head porting. Combustion chamber shapes. Oil pump and pressure. Spark plugs, Ram air systems. Etc.

We once spent an entire weekend running different oils through the motor on the dyno to see which ones made the most Hp.

Winner was Mobil 1, 5w-30.

So I believe I am very serious tuner and I do back up each of my mod's with data. I may not post the data but it is there.

For example my new cat-exhaust produces only 1psi of backpressure from the cats back. My intake heat spacers reduced the intake manifold temps by 30-50 degrees F.

And since there is no winner at the end of a modding spree I do not see the reason to go dyno test each and every little change. I do like to make several changes and then go dyno test to see how well the changes intergrate with the engine.

So I like to think that when I suggest or state an opinion on some change that may lead to Hp it is based on hours and hours of serious dyno testing and not just smoke and mirrors type guesses. Most of what I post is based on dyno work our team did on our race bikes, work that did see notable changes to engine performance.

Jeff

CKlasse
07-16-2003, 04:41 PM
STILL, I don't see why there is a need to undermine someone's "speculation" what's better for his/her car. :(

Back to the topic... as far as my little 4 cyl.. here are some of the goodies, I'll be using for the intake side -- keep in mind, I ll be running 14psi boost.

Air intake duct - lower grill
http://www.revotec.com/images/flexducting/id15075.gif

tubing to the custom filter box
http://www.revotec.com/images/flexducting/hoseblue.gif

I 'speculate' larger volume of air going into the Turbo! ;)

5.52
07-16-2003, 05:15 PM
Jeff- thanks for busting out the credentials...it certainly publicizes a degree of subject matter knowledge and track experience. I heartily encourage you on in developing and integrating as many race bike perf and tech into the MB and I support the spirit within which you offer mods ideas here

CKlasse- - no need to interpret as "undermine", and my post was not intended in that color......merely interested in seeing things from a clinical approach (test results)- - keep in mind this appears to be from a single perspective at this time and if others are not interested in it seeking the same and/or it is not a popular stance- - more power to everyone- - different interests and perspectives for different folks

...back in the dark Medieval Ages: when we tuned (bikes and cars), it required many test and tweek sessions;;;, test and tweek, test and tweek ...till finally the perf parameters contained the target characteristics...

5.52

Renn 208
07-16-2003, 05:23 PM
Really, I think that 5.52's original post should have been directed to most any other reader of the MB boards. Jeff, I'm sure you've noticed that the community of those who tweak and get measurable results are far outnumbered by the individuals who mod without verification. Similarly, those with track experience are very much out numbered by those without.

How many times have people posted poorly thought out mods that do little to the performance of their cars? Also, how many individuals out there look for chips, intakes, exhausts etc. to make their car faster while they neglect the two biggest areas for a beginner to improve in: driver skill and suspension? Why? because everyone can quantify HP, SPL, or even Wheel size...

I may be twisting 5.52's message, but in his own style, he's reminding everyone who has not developed to 9.5/10ths of their abilities that there may be cheaper and less time consuming ways to go faster.

Why mess with your airbox or spend $800 on a brand name euro exhaust when you can't drive a decent line? For the fun of it would be my guess.

CKlasse
07-16-2003, 06:32 PM
Originally posted by 5.52
keep in mind this appears to be from a single perspective at this time and if others are not interested in it seeking the same and/or it is not a popular stance- - more power to everyone- - different interests and perspectives for different folks


Exactly! back to the subject please :) :) ;)

speedybenz
07-16-2003, 08:53 PM
5.52,

You stated you have some racing experience. I hope you will share some of those stories with us so we can all gain from your experience as well.

Welcome to Club202.

Jeff

JasonH
07-17-2003, 10:27 AM
Wow, lively conversation... :nerves: You both bring up very good points/perspectives throughout the discussion, and I’m glad to see it appears to be ending with a positive tone. Clearly you both are two of the most technically knowledgeable on the board, and I enjoy and appreciate your input. :D

Hey Cklasse, it’s going to be interesting to see who ends up being quicker between the two of us ;)

I too am planning on running around 14 –15 psi of boost this time around. My car is finally getting pretty close to being put back together… yeah! When will you be up and running? One of the biggest hold-ups was Crower not being able to get their s$#% together & get my order out, & then correct. Did you end up getting those cams through them (can’t remember who they we farming that out to)? I decided to stay with the stockers. However, I did get some 30lb over valve springs with titanium retainers and caps from them... which took forever. Did you go with JE for the pistons? I am pretty happy with the Venolia’s, I just wish they would have built and delivered them a whole heck of a lot faster. Manley was great though, and my rods came very quickly.

Hopefully I’ll be up and running very soon.

Jason
www.TurboBenz.com

5.52
07-18-2003, 07:56 AM
Thanks Renn for re-phrasing...though peppered- it is apparently an unpopular perspective.

My apologies to Jeff as the original comments do not appear entirely appropriate based upon his talents, experience, knowledge, and spirit within which he posts.

As Renn and others can attest, I support MB enthusiasts both on the track and in the garage (gratis).

Jeff and Jason- thanks for the welcome feel free to PM me if you feel I can offer any useful perspective from my experience/ knowledge.

Also, let me know the next time you'll be going to the track, I'd like to join you, perhaps GTG!:D

CKlasse- re: the tubing- does it have some outer insulation? If not, in an effort to reduce the heat soak into the tubing you may wish to tightly spiral wrap the outside (with something like header wrap)- you may also wish to see if there is a way to ensure the inside of your tubing is as smooth as possible to maximize ram air...re: brakes- do you have some of that nice intake tubing directing cooler air straight to the brakes as well?

Be safe
5.52:D

Renn 208
07-18-2003, 08:02 AM
kinda off topic...but as far as I can see, Eurotuner fest has been canceled this year :( Claus...wassup wit dat?

5.52
07-18-2003, 08:08 AM
Renn- I checked a couple of weeks ago and ...looks like it is cancelled

5.52

speedybenz
07-18-2003, 08:13 AM
Renn & 5.52,

I completely agree with you both on learning to drive better and if people would do this they would be surprised at how fast thier stock cars cdan really go.

Renn can attest to how well my C280 went with a stock motor and some well designed suspension modifactions. My C280 out handles my C43 by a pretty good margin, but I hope to change that soon. My old C280 would have left my C43 for dead on a twisty road.

And for me there is no better thrill than to bend the steering wheel into a corner posted at 30mph while still doing 65-70mph. Feel the front tires bite and distort to thier maximum slip angle and then approuch the apex and feed in the gas, all the while feeling the rear tires starting to reach and surpase the limit of grip and go into a slow drift for a milimeter of time only to hook up again and drive out to the next turn.

This to me is very fun, and provided I keep it 8/10ths I have a pretty large margin of safety.

I wish more people could experience this type of driving, but realize it takes time and money spent at the track to develope these driving skills to point where they are second nature.

Jeff

BrabusCClass
07-18-2003, 12:08 PM
Hmm. Well back to the subject, after hitting the dyno about 20 times I can tell you that the Airbox does not suck in design. Acutally it sucks very good and channels air down much better (ram air) than a tube/pipe or K&N. I have been wanting ever since I got the kleemann to design a better intake but no prevail. MB did a great job with their intake. I dont think it was just for simplicity that they made it like that. I do hate the way it looks though since it goes right on top of the blower and you cant see squat. Oh well... my .02 :D

Renn 208
07-18-2003, 12:14 PM
J, you talking about a 43/55 airbox? on a N/A car?

BrabusCClass
07-18-2003, 12:25 PM
The airbox on the C240, looks bascially the same as my C43. I never tried to do anything with the C43 thou after I went crazy on the C36. Haha. I learned to leave AMG alone. :D Thats why i traded in the C36 and bought the C240 so I can go crazy on that. ;)

2phast
07-24-2003, 10:22 AM
Most of my performance decisions (Corvette) were not based on heresay or "seat of the pants" or even manufacturer claimed HP increase but by reviewing before/after dyno runs. I have continued this with my own vehicles, always performaning before/after dyno runs. While there can be variances between cars and dynos, when you see three or four positive HP increases, thats usually enough to rule out the odd fluke.

The inline 6 can definately benefit from a improved airbox although I suspect that a AMG airbox would be the logical route (for the non-amg vehicles) but there is plenty of available space to construct a cold air/ram air intake as well.

To substantiate your performance improvement claim, just perform a before/after dyno run, it sure will eliminate the conjecture.

Oh, I race as well, not as much as I used to as I am now a instructor but there is nothing more enjoyable than being handed your a$$ by a Cobra :D

http://www.2phast.com/C36/amgsir.jpg