Over the last few months, I have been debating about what to do with my car in regards to improving the engine performance of my 03 CLK55. I'm not necessarily looking to go a whole lot faster in so much as I would just like to be able to drive in the manner that I like to with less effort. I like the idea of being able to gently roll on the throttle from low-ish rpm and walk away from other traffic quickly, and quietly. Obviously I'm looking for more torque, but I would like to do so without compromising my top end power for those rare occasions when I'm really getting on it...

Note that I said that I'm looking to improve engine performance and not necessarily engine power, which leads me to my question about Renntechs ECU & airbox upgrade. I have been thinking about geting either an HPS, or Kleeman supercharger, which would MORE than take care of my goal, but I am reluctant to go that route because of the cost, and some concerns about reliability.

Obviously, with the Renntech upgrades supposedly delivering only 20 hp and 24 lb/ft of torque, we're talking about a fraction of the potential that the supercharger packages offer, but I'm curious if the numbers here might be a little misleading...

Just for the record, and to be absolutely clear about this, I'm well aware that the Renntech upgrade in question won't deliver anywhere near the performance that the two superchargers do, but I also think that the Renntech upgrade may do more than their low numbers might suggest...

For one, I read that while the Renntech package offers a peak gain of 24 lb/ft of torque, I also noticed that the torque peak comes in at a 1000 rpm less, 3000 versus 4000 rpm. I don't know how much torque the stock CLK55 engine makes at 3000 rpm, but if it's let's say, 6 lb/ft less than what it makes at 4000 rpm (Not an unreasonable guesstimate imho), then that's a actual gain of 30 lb/ft... Still not much, but more than the peak numbers suggest...

I also understand that Renntech's ECU eliminates the "adaptive accelerator" logarithim, and switches the stock throttle opening map for a much faster, and more linear throttle opening map of their own...

So my thinking is that possibly between the actual torque gains combined with a more asggressive throttle map, both may go some ways towards mimicking more power. Anyone who's driven either an E46 M3 can tell you how far a sharp throttle response can go towards improving an engines power delivery. At 269 lb/ft, the M3's 3246cc inline 6 comes up better than 100 lb/ft short in torque, but damn it if it's wickedly sharp throttle response (It does have ITB's afterall!!) doesn't seem to make up for a good part of that defecit!!

So, anyway, is anyone familiar with the Renntech set-up? Does my logic stand to reason in your opinion?

A big factor will be whether or not I will be able to add other upgrades without having to lose the Renntech bits later on, like an exhaust or cams (I can swallow having to have my ECU reprogrammed again for something like cams). I like the idea of keeping my engine naturally aspirated, and of being able to improve my engine in "steps", a few thousand dollars at a time rather than having to cough up $15000 or so all at once. Anyway, any thoughts and comments are appreceiated as always!


Best regards,
Matt

 

Matt,

You remind me of me. I have an '01 CLK55 and I, too, have been kicking around the Renntech airbox and ECU upgrade. I seem to have the same questions you have. I also stumbled onto POWERCHIP, as EvoSport markets that brand of ECU upgrade. They advertise significantly stronger numbers in HP and torque gain than Renntech (with no airbox, just ECU remapping), but Renntech seems to have the reputation for really knowing benz products and understanding how to safely and reliably improve them. I do NOT want a car with such dramatically advanced ignition timing that I run into detonation problems on a hot day. (these AMGs tend to run a little on the hot side to begin with). I am also a bit nervous about shipping the ECU cross-country and hoping it comes back safe and sound with no hiccups or glitches. I would be much more confident if these upgrades were available at a local shop where a trained mechanic handled the process and you had a place to go if there were any problems down the line. Finally, though not the same car, I did upgrade the ECU on my 92 BMW 850 with DINAN engine and trans chips and I was able to tell a noticable difference in acceleration. (Then I went crazee with Extrude Honed intakes, aftermarket exhaust, and a lower geared Limited-slip rear diff... WOW) Anyway... if anybody out there has first hand experience with either the Renntech ECU/Airbox upgrade for a naturally aspirated AMG V8 or with the POWERCHIP upgrade, I am very interested in hearing all about it.

 

I have the renntech intake (No renntech ECU upgrade, I have the Speed Tuning USA ECU upgrade). I never put my car on the dyno but I felt a difference when I put the intake on. The chip made it even faster. I dont know how much the airbox is going for nowadays but its pretty expensive. I like the way it looks and I am pleased with the performance. If you live in the DC area we can go take a spin. Anyways, I cant compare these products to anything else because I never had anything else.

 

I have the Powerchip, Evosport pulleys and K&N filters.
My car dynoed at the wheels 285 whp stock
The K&N and pulleys brougnt me to 294whp.
Now with Powrchip I'm at 310whp and 324tq.
I'm guessing my new hp it is about 375 crank hp and 410 tq
I'm very happy with my results. I have more Hp and better MPG. My car was running at 11.5 air/fuel and now is at 13.0 , which is perfect for a N/A car.

I thought about going with hearder but for $3000 with installation I have heard you only get 8whp. I have also heard the AMG intakes are some of the best out there, so I have not desire to get an aftermarket one. The only thing I would like to get is lower gears for my car. I think the gears will make the biggest difference. The M5 guys says the gears make a bigger difference than ECU, intakes, hearders, an exhaust put together.
Good luck
Mario

 

Did you go with the "Gold" Powerchip upgrade (the 93 octane version) and if so, have you ever had any detonation issues resulting from higher operating temp and greater ignition advance? Finally, did you pull the ECU yourself and send it in? Pretty easy DIY project? Thank you.

P.S. I think Harton Motorwerks can provide a 3.07 LS rear diff. for you car for about 2K. Stock is 2.82. That is about .25 difference. Multiply that by the 3.59 ratio for first gear. That would give you close to a .9 rev improvement in first gear. That would DEFINITELY make a difference for acceleration, and with a .82 5th gear, the difference in top gear cruising at 80 mph would only be about 225 rpms... VERY tolerable. I went from a 3.64 to a 3.91 in my BMW 850 which is a very heavy car and it made a noticable improvement in around town acceleration.

 

Not sure what chip i went with but I live in California with low 91 octane and there is no problem, I even took it to AZ and it was over 100 and still no problems. Powerchip did all the work for me since they are so close, they even gave me a renta car.
As far as the gears I'm going with a 3.27 which should be a 15% increase. Do you have the number to Harton Motorwerks and location?
Thank you
Mario

 

My mistake, it isn't Harton, its "Berg Werks" that can provide upgrade diffs for our AMG Benzes. Their number is 877-230-5736 or check 'em out at Info@BergWerks.com.

Good to know about the steady temp. with the pulleys and chip. I know one of the underdrive pulleys drives the water pump. I already think my CLK55 runs a bit hot. It gets well over the midway point of 80 degrees on the temp gague. I was told that AMG cars have a 90 degree thermostat and non AMG cars get a cooler 80 degree thermostat. I almost wonder if an 80 degree unit wouldn't be a good idea for a fairly aggressive chip and underdrive H2O pump pulley? Sounds like you haven't needed it, though.

 

I didn't want you guys to think that I haven't been paying attention here! So far, what I've read has been encouraging, but I'm hoping that there may be a few more first hand testimonials or maybe even some empirical data. I'm still waiting to hear more about HPS next gen intercooled supercharger, and more about the Vortech superchargers from "House of Power". I've always preferd the idea of a roots type, or positive displacement supercharger over centrifugal superchargers as they provide more bottom end power and a more linear power curve, but I read an interesting article in "Sport Compact Car" magazine that provided a good argument for centrifugal superchargers, and now I'm not as sure. Apparantely peak cylinder pressure occurs when an engine is at its torque peak, which is around 3000-4000 rpm for the na AMG 113V8, and at those rpms, the centrifugal/Vortech superchargers are making less boost so there won't be as high of a risk for detonation. A roots type blower will be making peak boost throughout the rev-range and cylinder pressures will be awfully high at peak torque rpm. An eleven to one compression ratio's awfully high for a forced induction engine, and I'm concerned about what engine temperatures will be like when I'm stuck in bumper to bumper traffic on a high 90 degree summer day...

Ideally, I'd like to do an intake/exhaust/ECU/cam upgrade, but costs of such an upgrade will surely be well in excess of $10,000!

How feasable would it be to buy a motor out of a wrecked CL/E/S/SL55?? Has anyone looked into that? While it will still cost a bundle, it does have the advantage of having OEM R&D and reliability, and I would imagine that my stock motor could be sold. I guess the trick would be to find a kompressor V8 at a yard that really doesn't understand its value...

Well, I guess I'll just have to keep waiting and saving! Thanks again for all of the responses!


Best regards,
Matt

 

Yep ,the roots type blower would definitely stress the 11 to 1 compression 5.5 because of it's capability to provide instant HP and TQ.It would be hard on the 10:5 to 1 5.5L motor as well. you can find a thick as hell head gasket to lower the compression to the 9's.That would be your best bet on top of studding the heads.


This is what they do with the E36 M3's.They use a thick headgasket(to lower compression),head studs ,then full turbo system with front mount intercooler from ActiveAuto 510whp.

Check out www.ICSperformance.com Keep in my mind stck engine internals.

Imagine what can be done FI with our MB 5.5L.It will be as powerful as the new 5.5L FI and almost as reliable IMHOP.This is what I would do if I go FI on my C43/55(lower the compression with thicker headgaskets and use the stck internals.). I guess for now I'll just stick to turbocharging my BMW and keeping my Eagle Talon.

 

Mario,you had no issues with the Air Mass and K& N filters?