B Feelgood

So I have a low mileage 2005 SL65 with the following mods.

-ECU tune
-TCU tune
-Catless downpipes
-4" intakes
-Billet BOVs
-Renntech cooling package

The problem I have is that the car doesn't really "feel" that fast. Flooring it or going WOT from a dead stop, there is a tiny amount of wheelspin but after that it's docile. It doesn't feel much faster or at all faster than my SL55. I understand tat the motors build and deliver power differently but it just doesn't seem like and estimated 700hp and 850tq.

I have attached a small data log. On my SL55 I'm used to seeing IATs 20 degrees above ambient when cruising and climbing to maybe 40 above going WOT but quickly dropping.

Maybe I have a huge boost leak and the pump is dead?

euphoriaDSM

A boost leak is obvious, the car will rev and you hear the turbos spool but you go nowhere. Look at the y pipe to the intercoolers and the flat pipe from the intercooler to the turbo. If both of those are nice and tight I'd go to a shop that has star and test your ic pump.

B Feelgood

I have a working STAR clone here. What's the procedure for testing the pump through DAS?

Jimshorts

I'm still feeling out my car after having an E55. It really might just be the turbos vs S/C. You really feel these 65s in the upper rpms. When your driving around what modes are you in and do you leave T/C on?

V12TTenthusiast

Those IATs and summer time heat will do it. Look into a trunk tank. Makes a huge differance. I have data logged when pump died and I'll get over 200 idle and 170-180 driving so I dont think its a dead pump. But with a trunk tank ill be in 90-130 until all the extra fluid gets warmed up but it does take much longer for the car to heat soak. Same can be said about cooling the tank down, but you can always open it and add some ice when you want to cool faster

BlownV8

Even in 90 plus degree weather, my 600 will instantly ignite the 335 rear tires. Something is wrong with your car.

euphoriaDSM

335? Can you pm me more info on your wheel/tire setup?

BlownV8

It's a wide body with 18x13 wheels in the back.

Ed954

Did you dyno the car?

AMG-Driver

I bet your IC-Pump is dead.

Constant intake temperature like 70-80 Degrees Celsius means there is zero cooling.

Was the same with my car and it made a BIG Difference with the new pump.

B Feelgood

Thanks for the suggestions everyone.

The ambient temperature during that log yesterday was around 93 degrees with a dew point of 71, so it was incredibly hot and humid.

I always just leave the trans in Sport mode with traction control enabled/on.

The pump that comes with the Renntech package is the modified Pierburg CWA-100.2. I called Renntech and they said the previous owner had the kit installed way back in 2008. I had originally thought that something may of been wrong with the pump so I wired it into the fuse box so it would be on 24/7 when in key position 2. It seems that the IAT's were the same as whenever it was being controlled by the ECU or even a little worse with it running all of the time. I actually have a brand new Pierburg CWA-50 pump here that I was going to install until I found out the car had the Renntech pump. However, I'm not 100% sure that the pump is dead?

I have a dyno session scheduled for tomorrow morning to get an idea of what the car is actually making. I also, made an appointment at Mercedes on Monday to have the coolant drained/filled/bled. I've done the coolant change on the 55k cars a handful of times as it's pretty easy but from what i've read, the 65k cars require a vacuum or pressure tool to get all of the air out.

Can anyone provide me with any tips for a smooth dyno session tomorrow? What is the correct procedure for enabling dyno mode on a 2005? The pull should be made in 4th gear and is 1:1, correct? Exactly where should the tech hook up for the tach/RPM signal? The shop I'm going to has a DynoJet 424X Linx.

Speedriven1

Second. Most common things to check are 1. pump, 2. boost leak, 3. intercooler not bled properly after IC pump/heat ex. upgrade. There's also the possibility that your ECU/TCU tune may have an issue, but that's unlikely if you went with RT.

AMG-Driver

Hmm,are you sure you have the Pierburg in the car because I think in 2008 it was not on the market. When you have air pockets near the pump it will not work. But your IAT definately is way too high and the hint that there is no real changing in IAT normally relates to not working pump. What are IAT when you start with cold motor? Near ambient or higher? When higher it could also be the IAT sensor which is faulty. Good luck!

Speedriven1

That's a good catch! I was working at RT in 2008, and we were using a Denso unit.

B Feelgood

Hmm, maybe it is a different pump? Here are a couple of pictures of the pump that's currently installed which I was led to believe was the cwa100 by RT. Without uninstalling it, these are the best pictures I could get. It certainly doesn't look like any other pump that I've seen before but I remember reading that RT changed the casing on the units.

Speedriven1

That's the Denso: http://sunshinesupercars.blogspot.co...to-forced.html

B Feelgood

Bingo! I scoured the internet for hours trying to find something that looked similar to that.

"Our previous generation intercooler kits utilized a race optimized Nippon- Denso pump. This pump offered extremely reliable performance and increased flow over the troublesome OEM unit and fit the bill for most performance applications."

I wonder what the flow characteristics of this Denso pump are? Is there any way to test the pump through Star to see if it's still functioning correctly? With the key in position 2, I can audibly hear it running. Also, if I squeeze one of the coolant tubes, I can hear the coolant running though it inside. However, I'm assuming that doesn't necessarily mean that it's running at 100% efficiency?

As mentioned, I have a brand new Pierburg pump here but I would hate to replace the Denso one if there's nothing actually wrong with it.

B Feelgood

I have read a few threads stating that other 600/65 members couldn't get a torque reading from a dyno due to their shop not knowing where to tap for the tach/RPM signal. Where is the best place to to do this on the V12 TT motors as I'd definitely like to get a torque reading tomorrow morning?

Speedriven1

Injector pulse or cam sensor at the back of the engine.

RaceHorse

I could never get a torque reading off a dynojet. I was told an "optic sensor" was required to pick up RPM and every attempt, at a few different facilities, were always unsuccessful at getting it from an injector wire. Good luck getting things sorted out. It sounds as if you are headed in the right direction. Bad enough driving in summer heat feels like giving up 100HP.

B Feelgood

At the dyno now!

MTV10

Report back with the #'s ! !

Ed954

The car looks great BTW!

Jimshorts

Can't wait to see the results. Personally I always have the car with ESP off. I've noticed a huge difference. The car feels like it is cutting power and tq when I have it on playing around.

BlownV8

Those big a$$ wheels.won't help your power but they do look nice.