Brabus SL

Hi all , I have a 2003 SL55 AMG Based BRABUS SK55 K8, I would like to find out if anyone knows what the "Charge Air Temperature" for a standard SL55 AMG should be, I recently had my car put through the STAR diagnostics and my "CHARGE AIR TEMPERATURE SENSOR" and "INTAKE AIR TEMPERATURE SENSOR" values are 50 C, is this normal, I had my car put on the Dyno and I should have 550 hp, instead I have 510 hp, where has all those horses gone??? I was told that my temperature may be to high causing the ECU to reduce the engine power!!!

Thanks in advance.

Benz-O-Rama

Probably a bad I/C pump. Very common in the 55K cars.

Brabus SL

Thanks for your reply Benz-O-Rama ,
tell me, If it was a bad intercooler pump would it not show up on the Star Diagonostics as a fault, also does the temp seem to be a normal reading, especially as it is has a BRABUS modification (additional intercooler and addiional intercooler pump?) I was not sure if 50 C was normal, even for a standard 55K engine

jmf003

If I'm doing the math correctly 50C = 122F, which should be okay. Forum wisdom holds that the ECU starts reducing power when the intake air temperatures rises above 140F = 60C.

The missing 40 HP could be due to any of a number of factors, including dyno setup and fan cooling. For that reason a lot of guys measure their performance changes by track numbers rather than dyno numbers.

Unfortunately Star Diagnostics won't throw a code until the pump fails completely. When the pump is still limping along, Star indicates no problem.

For what it's worth....

Brabus SL

Thanks for the info, what I am confused about is that I dont think that there is an issue with the Dyno cooling as I today put the can on another Dyno run at another specialists garage and received almost the same results! my friend has recently purchased a 2007 CLS55 AMG which is standard and I beleive it has around 476 Bhp, I believe even a standard 2003 SL55 AMG has around 496 Bhp and weighs almost the same as the CLS55 AMG so with all my BRABUS Mods (Pulley, BRABUS ECU Remap, Sports Cats, additional Charge Cooler and an addition cooler pump, how could I only have 510 Bhp and even with all those mods the CLS begins to creep up to me between 90 mph and 150 mph and if it was not for his limiter he would most likley pass me. I think all he would need is a good ECU Remap and he would leave me standing, that can be right, unless there is something wrong with my car, which is what I am trying to find ou but it is proving difficult to find someone who knows or or understand the issue I have!!!!
I am going to contact BRABUS in Germany I hope they are going to be helpful. I must point out the there is no BRABUS in the UK, the Cars are sold through MB dealership but the dealership are useless, they are only used to selling BRABUS Body Kits and giving you free cups of tea!!!!
I am thinking of buying the johnson Charge cooler pump.

Brabus SL

Just came of the phone from speaking to BRABUS in Germany, the technical person I spoke to was very helpful, among the things he suggested was to send the ECU to them and they will remap it for free as during the cars life Mercedes Benz may have upgraded the software during a service, clearing the original BRABUS ECU remap!

The other recomendation was to remove the Charge Coolers (Mercedes & BRABUS) and clean them out and/or replace the BRABUS Chargecooler Pump and the Mercedes Benz Charge Cooler Pump.

Or Bring the car the BRABUS in Germany and they will check it !
seven hours drive away!!!

sprins

Do that. Have them check the car out thoroughly. Get a loaner from them and enjoy some of Germany. Make a short vacation out of it.

If you like wine: http://en.wikipedia.org/wiki/Ahr_(wine_region)

Brabus SL

Hi All I think I am back!! (Maybe)
MotorAid checked both pumps on my car and found the AMG (Bosch) pump not working at all! so only the smaller BRABUS pump was operating and its job is to only pumping the water around the smaller additional charge cooler, the water was not flowing through the larger AMG charge cooler causing the Supercharger temp to rise to high also causing the air intake temp to also rise. The faulty AMG pump did not show up in Star as the BRABUS pump was wired in parallel to the AMG pump therefore there was still a resistive load telling star all was working. my "BRABUS" power seems to be back now albeit my charge temp at idle still remains at 50C but at driving on the proving ground the air intake temp sensor measurement was recorded as follows.
40 MPH -38C
50 MPH -40C
70 MPH -42C
80 MPH -57C
90 MPH -60C
100 MPH - 61C
120 MPH - 58C
130 MPH - 77C
140 MPH - 73C
150 MPH - 75C
I was told that the Air intake temperature readings are to high causing power loss but the car feels more punchy! Its very difficult to find ot what would be considered to be normal as BRABUS say 50C at idle is OK but two independent Mercedes Tuning specialist say its to high and it should be between 30's and early 40's and not 50C, apparently Mercedes state 50C is the Max, but with all my additional BRABUS cooling the temp should be considerably less! not quite sure what to do next if the air intake temp is to high, I have now changed my air filters to BMC Air Filters which contain no oil like the K & N filters which I have read the oil from the K&N Air filters can damage the MAF sensor, not sure if the is true so I did not want to take the chance.
I will have to compare with my friends CLS55 AMG, yesterday he has it remapped by Evolve, prior to his remap he told me he had his exhaust mid-boxes removed which may have given him additional BHP when we first compared the performance of our cars, he now has 535 BHP from his Dyno Run, i will be seeing him soon!

contigo

I am getting hot coolant temp when driving hard very close to the top 120 reading, should i look at what is mentioned here?

Brabus SL

Hi Guys of Wisdom,
I would like some help here please, I understand that you guys in the USA are great fans of the AMG V8 55K Engines, over here in the UK it is proving vary hard to find a specialist that can help me with the problem that I am having with my BRABUS K8 Modified SL55 AMG, as I have mentioned previously I am experiencing what seems to be a loss of power, let me explain.
I have a 2003 SL55 AMG Modified by BRABUS in Germany,

This is the specification I found from Wikkipieda

"The BRABUS K8 performance kit for the top-of-the-line SL model (SL55) comprises modifications to the supercharger drive in the form of a custom vibration damper and a new pulley for improved belt- drive geometry, high-performance metal catalysts, and an auxiliary circulation pump with opposing radiator. The power developed by the modified supercharged engine is increased from a standard 476 hp (355 kW)to 550 hp (410 kW) at 6,200 rpm. The maximum torque is 780 N·m (580 lb·ft) torque at 3,000 rpm. After the power treatment the roadster races to 60 mph (97 km/h) just 4.1 seconds, passes 120 mph (190 km/h) after exactly 13.6 seconds and reaches an electronically limited top speed 186 mph (299 km/h) with the limiter removed top speed would be well over 200 mph (320 km/h)"

Now here is my problem, I have a data logger which I now use to measure my IAT as I think my car looses power under hard pulls, I am not sure what my IAT should be before my power starts go, what should my IAT read above the ambient temp, is it 10C above? I am finding several cars pulling away from me from 50 mph, cars such as CLS55 AMG (standard) CLK63 AMG (with ECU Remap 510bhp) BMW 335! (380 Bhp ECU remapped only) once upon a time I would leave Lambo Gallardo 520Bhp EGear, Aston Martin DB9, Porsche 996 911 Turbo off the line and from kick down from 50MPH. from a standing start I am off but it seems that the harder I go the more power I loose, I raced against my friends modded CLK63 (ECU Remap and Mid Silencer removed) and he leaves me by about 5 car lengths from 50 mph to 140 mph!
Yesterday evening the ambient temp was around 18.5C and at 100 mph my Data Logger was displaying a IAT of 79C and the CLK63 was pulling away from me HARD!!!
So today I decided to check my IAT before I started my car, the Ambient was 20C but my IAT reading was displaying 48C as soon as I started my engine, this made me think, "is my sensor faulty and giving an in correct reading to my ECU causing the ECU to think the charge cooler temp was to high and adjust the timing, dump fuel then cause the electromagnetic clutch for the S/C to disengage (how do you check if the sensor is faulty and where is this sensor located, maybe I have an air lock in the charge cooler system, a faulty charge cooler pump, I have had my car on a Dyno and it reads 510 Bhp, a year ago when I first noticed that I had power loss I took it to a Mercedes Tuning Specialist and the said a remap may solve my problem, so i agreed to have a remap, recently I had it put on another Dyno again and it achieved 510 Bhp I then had my ECU altered by the tuning specialist and the BHP went from 510 bhp to 567.1
below is the readout


There is no BRABUS network dealership or Technicians in the UK and MB dealers don't have a clue on where to start! this is really stressing me out as I have what should be a Great Rare and Fast Car, but maybe its not as fast as I thought and just rare and looks good!






You guys have a much hotter climate than us in England so I am sure you are faced with excessive IAT, I hope you guys can help.

Thanks in advance
Cliff

jmf003

I agree that your IAT readings are too high. Try replacing the intercooler pump (also known as the charge air cooling pump). It's quick, easy, and not that expensive as Mercedes repairs go.

Good luck!

Brabus SL

Hi jmf003 thanks foy your reply, I forgot to mention that I had changed the I/C pump around 200 miles ago as the Bosch pump had failed, my car has 2 I/C pumps and they are both working!

is it possible that the IAT sensor is faulty?

Brabus SL

Hi all, I have changed my IAT Sensor hoping that was my issue but it has made no difference, my next step will be to flush the charge cooling system, clean the charge cooler fins then get the MAF cleaned. Can any one tell me when you plug a Data Logger in to the ODB port what sensor is it reading for the IAT.

Is there more than one temperature sensor?

Is there a sensor that reads the coolant temperature that flows trough the charge cooler system and what temperature should I expect to get for a standard SL55?

Using a temperature measuring device where is the best point to measure the Charge Cooler temperature from?

At what temperature does the ECU start dumping fuel and disengage the clutch for the Supercharger?

Am I right in thinking that the IAT sensor located just under the throttle body only reads the temperature of the air coming in?

Thank you in advance.

Sunir

What is a "custom vibration damper"? From my understanding the harmonic damper is part of the pulley assembly, so does this mean that they put on a bigger pulley and belt? Other than that seems like all they did was swap cats and add a secondary H/E and a secondary I/C pump. Did they tune the car even?

How much does the K8 package cost? Seems like just a few very basic cooling upgrades, pulley, and performance cats??

Brabus SL

I am the second owner of the car, the original owner had purchased the car directly from BRABUS in Germany which is where all the modifications were done, from what I understand the K8 kit in 2003 cost around £13,000!!!! all of that for an extra 50 hp! that also excludes the BRABUS body styling, BRABUS Monoblock VI wheels, BRABUS exhaust, BRABUS lowering module, BRABUS 220 mph speedo, BRABUS V max removal and interior upgrades.

Oh and yes BRABUS do include an ECU Remap!

Sunir

Well the car certainly looks fantastic!! Even if only 50hp, I think the main up- sell point for the package is all the other interior and style upgrades that make the overall car a Brabus.

Brabus SL

I just wanted to add that with the additional work on the car carried out by BRABUS the total bill including the engine performance upgrade totals over £56,000 excluding the cost of the car or Mercedes Benz extras!!!

Sunir

So does the Brabus K8 package (including interior, exterior, and 50 hp of power upgrades) cost 13,000 BP or 56,000 BP?

Brabus SL

In 2003 the total cost of the modifications, interior, Exterior and engine mods carried out by BRABUS came to a total of £56,000 BP, plus the cost of the car £1000,00 BP a Grand total of £156,000 BP

Sunir

holy crap that's rediculous ...there are SOOO many other cars I'd rather get for that price point that would better the Brabus K8 in most every way comparatively!!! Ferrari, Lambo or Porsche just to name a few even as competitors in '03 with money spared to mod the car. That's crazy money for only 50 or so more bhp...I'm not so much into interior or appearance mods...

contigo

Does anyone know if the pumps on the 65 are similar to the 55? Any one have a DYS instructions for replacemnet?

trabots

I searched IAT sensor and came up with this thread. I sent off my AFRs from a 3rd gear 3,500-6500 rpm run from my just warmed up (SL55). They started in the high 11:1 (11.99) and richened to mid 10:1 (10.56) at 6,500 rpm. My exhaust tips are sooty black confirming the rich condition. I know AFRs for S/C engines are kept lower than N/A engines for safety but I can't help but think there is more to come with leaning things out up top. I can do several runs without slowing indicating my IATs should be ok. I measured the water right after the I/C at 90F after a hard run so I don't think hot IATs are the source of the rich AFRs. What do you all think before I argue with my tuner who wants to keep things where they are?

My car has a 77mm pulley, belt wrap kit, dedicated water tank, extra H/E, Piersburg 50 pump, bigger T/B and injectors, shorty headers (stage 3 kit), no cats, K&N filters.

trabots

The tuner leaned out my AFRs with immediate improvement in 100-160kph time, 4.1sec down to 3.9sec. The best my car could do stock was 4.8sec but for only one run before heat soaking. My car with a separate tank, does not heat soak anymore.