Renntech CF Airbox Installed - Review

I am on the quest for 12's N/A, having high flow filters, Kleemann Headers and tune, the Renntech box just seemed like the next logical step.
Figured, I would compare the AFE Dry Flows vs the Stock filters first.


If you notice the AFE filters, are much thinner than stock. While the K&Ns are even thinner the the AFEs. The quality of the AFEs are superb, however, fitment was much better on the K&Ns. On the AFE's fitment it takes some finessing, as they seem about 1mm to short. Going oil-less was worth the compromise IMO.
Now on to the CF box.
Next to each other on the work bench



Notice the CF is much taller than the stock box, right around a inch. Or 50% larger.
What do they look like inside though? Stock Box

Renntech Box

This is where I see the biggest the difference. The renntech box is completely baffle free. That combined with the larger space, I can see how these are making more power at the wheels.
Before:

Installed:

Installation was simple of course, though getting that front vanity cover on was a bit of a chore. Since the box is much thicker than stock it will take some oopmh to get it to clip in.
Driving Impressions:
There is a definite increase in throttle response and the sound did change. I love it. Reminds me of the days on carburetor engines when you flip the air-cleaner lid upside down. Much deeper and louder, sounds fantastic. I can also honestly say I felt an increase in the **** dyno as well.
Overall, I would say the Renntech CF airbox is worth the freight if you can find one used. There are at least 3 independent dynos now showing a consistent whp increase ranging from 10-20whp. I have no reason to doubt those gains. Thanks again Betrezra for selling me the box.
Track time will have to wait to spring as winter is official here.
The CLK55 is now in storage and winters are on the ML55.
Next up, high flow secondaries and perhaps a retune on a dyno.
Last edited by Nachtsturm; Dec 12, 2011 at 12:42 PM.
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1895$ is pricey! Renntech is general is just overpriced!!

My goal is anything in the 12's and 110mph traps. The needswing dual CAI, is that actually coming to fruition? Thought it was nixed. Be great for people to have more options.1895$ is pricey! Renntech is general is just overpriced!!

If you find one used, I'd buy it. Don't forget at the 1895 price, you also have to sacrifice your stock AMG box.
It is expensive, but it is the best option out there for intakes. You could do an E55 intake, but remember Hooleyboy's dyno'ed the E55 intake and Renntech box back to back. The Renntech made 15whp more. Also it seems a decent E55 complete setup is around 450ish, I would just spend the extra 4-5hundred and get the real McCoy.
What I do is lift the back end and gut the inside and make it smooth for a much better air flow than stock.
With that done the engine breathes much better so it makes power and has better throttle response.
This is just and overview of what I do, it's not an easy job but worth the time and effort.
The price is $480.00 shipped within the USA.
And I provide the top air box so you can keep your stock one.
All you need to do after receiving my air box is install your filters and the covers.
Than install it on your car like normal, fits like oem, no issues to deal with.
Take it for a drive for a few hours and you will LOVE how your car now performs with my speede43 air box. It will rev so much better thoughout all RPM'S. Throttle response is everywhere, my air box will make your engine come alive.
The dyno showed 10HP/10TQ for the C43 air box, your air box will make the same or better. I do not have a dyno on your boxes yet, but the power will be there.
Thanks for reading.
You can contact me at speed43mods@gmail.com if you're interested or have questions.
I take payments using PayPal. I'm 100% legit, check the reviews, the guys that bought the boxes from me are not friends or family. They are long time forum members and their review comes straight from them.
https://mbworld.org/forums/clk-class...ml#post6833940
Last edited by speed43; Oct 7, 2019 at 11:43 PM.




Here's one I modded and also painted the front cover to match the box. I also did the same setup in flat black for a customer. 385 with customer providing the air box.

Unfortunately I am in the Middle East and so sending my airbox over is a bit difficult :-(
speed43mods@gmail.com
speed43mods@gmail.com
Any with Sascha Greiner’s signature? ;-)






