Looking for a RennTech air box for my W208 CLK55. Wondered if maybe someone had opted for that upgrade on a lease vehicle and removed it prior to returning the car at the end of the lease. Or, maybe you are selling a W208 and want to sell the upgrade parts separately? Let me know. Thanks!

 

Why don't you just get your box covered in carbon fiber? The RennTech box is the exct same box you currently have with carbon fiber on it.

 

Josh, you make a valid point. I guess I was just hoping to get an actual RennTech piece if one is available. Even though RennTech advertises that their air box is worth a few ponies and a few lbs of torque, it looks suspiciously like a factory unit in carbon. I have been told that the RennTech unit is a bit deeper looking from the side (profile) where the filters insert so that there is a bit more room for airflow. I have also been told that having the whole box in carbon fiber (rather than just a thin veneer for looks) insulates against under-hood engine compartment heat and keeps incoming air a few degrees cooler than that factory plastic. Only a before and after on the dyno will tell for sure. If I find one, I will do a before and after test and post results!

 

ever open up a RENNTech airbox and compare it to a stock airbox???... air channels are different and have in fact been researched, modified and tested for better airflow allowing more HP and TQ and a freeer breathing engine!!!

 

Different from a 430 airbox, yes. But not from a CLK55 airbox. In case you don't already know, Renntech doesn't really fabricate anything of their own. They just about always use Mercedes parts and simply package them as their own. Ever compare Renntech Cams for a CLK430 with CLK55 ones? Identical. Ever take a look at a "Renntech" supercharger? I'll be damned it it isn't an AMG part. Ever put the Renntech Box next to a CLK55 box? Also identical. The Renntech box does breathe freer - than a CLK430 box. The gains you would get by putting it on a 430 are the same gains you would get by using the CLK55 box (because it's the same box). But changing a CLK55 airbox with what is essentially the same box? Sure, it's carbon fiber and looks cool, but you won't get any more power - unless you think stickers and carbon fiber increase power.

 

Ever compare parts for the 55? For your info, RENNTech does custom fabricate in house things that need to be done in house. R&D? Yes they do a lot of R&D. RENNTech uses what they feel is sufficient for a car... what can be better in quality then using OEM parts and modifying them to be better? Ive opened up the airbox on my buddies 210 E55 and opened up the RENNTech CF airbox on my ML55 and they are DIFFERENT inside. About the supercharger... you living in the past.. RENNTech did use AMG chargers b/c they have a very efficient design for airflow. For low boost applications and most high boost applications RENNTech is using a completely different supercharger system now.. it is a Lysholm style Autorotor supercharger and a custom fabricated airbox/intake system and in house designed intercooler system that is more efficient then the AMG intercoolers. Headers, intakes, and such were also designed and tested inhouse. You need to stop spreading false rumors that you "think" are correct and do a little research.

 

Of course the airboxes on a E55 and an ML55 are going to be different - the AMG boxes are different between the two cars! If the Renntech box really is "better" than the CLK55 box, show me the independent dyno numbers to prove it. FYI, I've opened up the box for the CLK and laid it right next to the AMG box. The only difference? They cut out the air channel that guides the air. Plenum size and shape is identical. Those intake runners are not present on the CLK430 airbox and AMG (also a tuner - with more R&D $$ than RennTech) put them there for a reason. But again, if you think the deletion of these runners gives a gain over the hp the CLK55 box gave me and is thus worth the extra 2100 bucks, post the dyno numbers.

 

How bout something better then a dyno chart anybody can pull out of anywhere and claim it to be a dyno chart from w/e mod...


I wasnt talking about just any ML55, i was talking about MY ML55... so your saying that this ML55 airbox setup is completely differnet from that of an E55..



Again, the RENNTech airbox is different inside then the AMG airbox is. Also, the back area of hte airbox near the MAF is a lot better flowing...theres less restrictions in that area b/c its a larger area.


When we put the RENNTech airbox on we did notice that the engine sounded "louder" due to better breathing, and thus more noise could be the reason why AMG did not design the airbox to be like the way RENNTech modifies it to.



see for yourself...


its also funny that when some ppl do intake mods to the M112, M113, or M104 motors that they end of screwing up the MAF... ive had the same MAF on my car since the RENNTech airbox and have never had a problem.

 

Maybe you should talk to Ben Kleinberg (formerly of EvoSport) who actually had first a Renntech box on his CLK430 and later a CLK55 box on it (before he got his Kleemann). When dynoed, the Renntech box showed NO gain (if I remember correctly it actually lost about 1 HP). The CLK 55 box on the other hand netter about 21 HP in conjunction with K&N filters (which the RennTech box also had). These are dynoed results on the same car.

The fact is, the Renntech box cuts out the intake runners which are necessary to guide the air to the center where the MAF is located. Taking these out leads to less directed airflow. I notice that the Renntech box also removes the screen before the MAF. I tried removing that screen from my Saleen and lost about 4 horses. Turns out the screen was necessary to break up the airflow so the MAF could take an accurate reading. Obviously the Mercedes is a different car, but looking at the dyno numbers between the two boxes on the same car, I'd probably leave that screen in. ;0)

I understand you're a RennTech dealer and I'm sure they sell some good AMG parts. But I'm just talking about the airbox, and besides looking nice it doesn't really do much.

Incidentally, do they include a replacement lower cover section to replace the original AMG one? I would hope so for all that $$$ cause the c/f with the OEM plastic just doesn't look right...

I've had the AMG box with K&N's on my car for the better part of 50k miles with no MAF problems. As my car is getting supercharged this summer, I'll be listing it in the classifieds soon.

 

Of course Ben is going to put down RENNTech, it was his competitor. I am not going to get into the tuner wars here b/c we obviously know who runs this board. As far as RWHP gains on the dyno... I dont have a dyno chart here to show you... as far as track results, i can guarantee you that YOU WILL see and hear a difference using the RENNTech airbox. All ill leave that with is that its been proven on the drag strip.

The bottom peice of the airbox is replaced, the whole airbox is replaced... RENNTech simply uses teh bottom peice they purchase from AMG and modify in-house. Its like buying the top quality metal and machining it... why refine your own metal?

As far as the screen being there to break up the airflow... wow, some1 needs to lay down the crackpipe. I bet whoever told you that has one of those "Tornado" things in their intake as well...lol. If you want to break up or disrupt any airflow, why not go with Mann OEM filters? You think a peice of chicken wire is really going to make that much of a difference to distribute airflow evenly? Hell, why even put Green or K&N filters, lets put a paper filter instead. Listen man, I back up what I research myslef, whether it be Carlsson, MKB, RENNTech, Evosport, MRP, Irish Mikes, w/e products... the truth is the truth and what is in front of my eyes to see is the truth to me. Some ppl just suck up what other ppl tell them with closed eyes. I dont care about dyno charts and time sheets, hell, go to the track and see the car run yourself, go to the dyno and see the car being dynod there yourself.

Im all for DIY and cost effective mods.. I have a couple myself, but sometimes the truth is the truth. There are some things better left to other ppl with more R&D and experience. It is just up to you to do the reasearch and make the right decision about who you are leaving your car with and what you want done to your car. Be there and see results in front of your face, not walk into a room blindfolded and do everything the first voice you hear in teh room tells you.

 

If Ben was going to put them down then why did he spend his money to buy the box? LOL He bought it cause he thought it would make a difference and it was dyno proven otherwise.


As for the "crack pipe," breaking up airflow is very different than restricting the airflow.

If it doesn't, then why does Mercedes put it there?

Too bad you're in Florida, there's going to be a dyno day at the House of Power on the 27th of this month. I'm going to find someone with a Renntech airbox and dyno my own car with the 430 box, the AMG box, and the Renntech box and end the debate once and for all. I'm sure you won't trust my dyno numbers but if you're not really open to reality unless you, yourself see it, then I don't know what to tell ya. ;0)

FYI, I do the research myself as well. I was planning on getting the Renntech box until it was shown that it offered no gains and that the AMG box did (and was over $2k cheaper).

 

I dont knwo why Ben spent the money on the airbox and frankly i dont care. Restricting and breaking up, blocking airflow...same ****!! It still contributes to restricting air from flowing through... i bet your a beleiver in the "tornado" POS too huh. Yea, too bad I'm in FL, id love to come to Cali and prove you wrong, maybe even race that supercharged 430 of yours with my little V6 kompressor. You keep mentioning those fins inside the airbox... well have you looked and measured the volume of air on the top part of the airbox? The RENNTech airbox has a much larger capacity. It looks like you did your research but only based on what one person told you. Yes, the RENNTech airbox is much more expensive, but yes it has gains, not phenomenal gains (unless you did the conversion with the ML) but there are gains, especially at higher RPMs when the engine is running out of breath. Also, CF is not cheap... the labor cost it takes to build the boxes in house is not cheap as well. You did research, but do a little more next time...

 

After all this arguing about the renntech airbox I went to the dealer yesterday and talked to a few techs as well as put the renntech airbox side by side with a CLK55 airbox. I used to think they were the same like Josh. But in reality they are not! Besides all the differences bezoamgpower has mentioned, the top half of the renntech is larger than the AMG, thus increasing airflow. Therefore making more power. I would like to do a dyno between the two to see the difference in hp/torque but I dont have a CLK55 airbox. If someone in the DC area would like to donate their airbox for an hour and split dyno costs I would like to put this debate to rest. By the way, a dealer of any product is biased.

 

As I've been debating on buying a Renntech airbox, but have been hesitant because I don't know if it's proven to increase horsepower. It does sound to me that while the Renntech airbox looks similar, there are some differences, but the question is whether or not those differences help it to make more power...

I also want to add a couple cents to some of the points made in this thread...

First of all, I don't agree that breaking up airflow is the same as restricting it. While I personally do not know enough about MAF sensors to know if turbulent airflow gives a more accurate reading or not, I do know that trubulent airflow IS beneficial inside the combustion chamber.


Secondly, while it seems to stand to reason that a larger airbox flows more air, and hence more power, that may not necessarily be the case. Things aren't as what they would seem to be when you're talking about aero and thermal dynamics. An increase in airbox volume could lead to a decrease in air velocity which is critical in cylinder filling. It's the same reason that intake ports only need to be "big enough", and hogging them out can lead to a decrease in power. Now don't get me wrong, I'm not disputing what Blackbenzz is saying as he very well may be right. I'm just saying that it's not necessarily a fact that a larger airbox increases horsepower.

While we're on the subject of Renntech, does anyone now why they are so incredibly expensive? I don't think that the cost of their airbox/ecu kit is unreasonable (It's expensive yes, but not extraordinarily expensive) and some of their suspension bits are reasonable, but some other items are insanely expensive. The two best examples are the bigger crankshaft pulley for the E55 that costs $2495 (!!!!) and their headers which are $3995!! Am I missing something here? $4000 for headers?!? Hand-made or not, that's still very, very expensive. I'm also curious about how it's offered for the C55 and not the CLK55... Aren't the front ends of the two cars virtually identical? I really wish Renntech would bring the price down and offer it for the CLK55 as I'm desperate for some headers as the OEM manifolds look about as restrictive as they possibly can be. If any car will benefit from headers, it's the AMG V8's!!

Anyway, I appreciate the info I'm learning here, and I hope to find out what the real deal is...


Best regards,
Matt