Hello all,
I am building a W205 C63s 2016 w/ 25k miles. I am currently at stage 3~ with plans to move forward 4,5 etc. The car is underperforming. We have done numerous passes and re-tunes and can't get past 540whp. Max at Benz has hooked up to Xentry and we have No codes, No lights, Camera/snaked the interior engine block no damage (some hotspots little pits nothing crazy). Exhaust has been smoke tested. Plugs have been changed three times from OEM's to HKS colder plugs. We had initial issues High IAT's which we diagnosed was a bad water pump. We then had knock at idle and WOT with fresh benz plugs to which we then swapped for colder plugs, emptied gas tank did fresh 93 and solved the issue. After these two items were sorted we finally were able to a few consistent passes 520-540 on a Dynojet. However these passes were at around 29-lbs of boost the car is nowhere where it should be and the dyno graph indicates so aswell. Before we re-tuned my car we did Charlies from Vintage Motoring C63. He has a C63 w/ e63 twinscroll turbos, same supporting mods as me. However he has a AWE track exhaust and Catless Downpipes. He did 585whp.
We used his same file on my car and did like 426whp.....!!!!!

The cars software is up to date. We've tuned and retuned. The car is hitting boost targets. I am at a wits end with this and so is my tuner and both performance shops that are assisting.
I would like to preface this discussion by stating that everyone involved in this project has and actively are assisting me with open doors and excellent communication BAR NONE. I feel like we are hitting a wall and not seeing something which could quite frankly be simple or overly complex to get the full potential of this car.

After having done all those deductions we crafted another list of possibilities;

1. Catted Renntech HighFlow DP's might be restricting
2. I myself think maybe soft limp mode because of battery? (the car was at the shop for probably 3 weeks, paint corrected, its not my daily)
3. Charcoal canister? idk I read it somewhere else on the forum
4. Exhaust flap thing? There should be a code?

Performance Shops: Vintage Motoring and Mbenz Motorsports in South Florida
Tuner: Edgard at @DSMLights
Product Sponsors: Cris at Modal Works and Zane for Zefer Performance

Current mods;

1. Modal Works Cooling Kit (center and auxiliary),
2. Zac Intakes w/ Shields,
3. GAD Blowoffs,
4. Renntech Catted 200cell Downpipes, (No AMG Performance Exhaust -Just OEM Exhaust)
5. Pure 900 (calibrated at 12~ HGSI),
6. One step colder plugs gapped @ .22 (recently installed)

I would appreciate if any fellow C63 build's chimed in with any issues they ran into or plausible explanation.


The graph has TWO OVERLAYS Top is C63 with Catless DP's & e63 Twinscroll Turbos Bottom is C63 w/ Catted Highflow and Pure 900
Top car did 585 HP at around 23lbs of boost vs. My car did 540 HP at almost 29lbs of boost

 

Couple of thoughts. E63 twin scrolls are better than pure 900's, why is the E63 turbo'd car only making 580whp. A stage 2 PTG car made 570whp / 705wtq on a dynojet. Why are both of ya'lls numbers so low.

 

That’s strange cause my pure 900 with modal works intake makes around 700 to the wheel. No meth, just catless dp & 93. I’m try to find my dyno and will post it on here.

 

Second pass after some table work car did 600hp easy. The boost levels are around 23lbs. That 585 number was after multiple passes, heat soak, and hot dyno room. I’m sure if we did a cool glory pass the car would easy be above 600whp.

My car however did 426 on its first pass with that same file. It was not heat soaked. It had spent more the most part 3 hours just chilling outside in cools weather with the hood propped up. So cool in fact you could touch turbos and they were barely luke warm

 

Your input is appreciated.
We are guesstimating the CATLESS dp would help over the 200 cell Highflow. From my understanding there shouldn’t be that much of HP loss or increase just from catted to catless. Ofher members are doing better numbers than i am with less mods.

 

Dyno numbers vary wildly between different dynos or even the same dyno on a different day. The best test of your car’s performance is with a Dragy or at the drag strip. Do you have a Dragy? If so, post up your 1/4 times with trap speed and your 60-130 times.

 

Who is your tuner? How are your AFR’s? Are you sure it’s not a fueling issue? Are you seeing any knock during the pulls? What kind of timing/spark advance are you running. Catless will help but probably not your biggest issue. My car made 540whp just tuned with downpipes and no intakes on 91 Oct only making 18psi. Stock gapped plugs. Zero misfires or knock. Something is up here.

 

That is very strange. You should definitely be making more power.

That C63 with the E63 twin scroll turbos, where did he source the E63 exhaust manifold?

 

Thankyou for this. I just ordered the draggy. Will be doing a few pulls and reporting back. I got trashed today by another c63 did not feel good lol

 

edgard @dsmlights is my tuner here in Florida
very competent tuner.
we have been slowly but surely remediating issue that have popped up. As of now nothing really jumps out to him at the dyno. But there’s always a chance were also missing something in the logs.
another member on facebook mentioned checking the pumps. They jad a similar issue where on lpfp was a bit weaker and starved the car on top. I plan on getting the car hooked up and checking pumps

in regards to dyno i do think another member touched on this is they are calibrated differently or they are of a different type. My point of reference is a car that was tuned an hour before mine. Beyond that the tuners own results on the same dyno albeit other variables can affect and come into play but the general consensus is i show to be underpowered.
the draggy 60-130 will tell a full story.

 

He did this swap about 6 years or so ago. I’m asumming when parts where a bit more accessible and there was also no aftermarket product offerings that were bolt on at that time.

 

Are you sure pure didn't send u back stock turbos ? You need to bleed the hell out of the heat exchanges with xentry to get them done right as the car pumps them at different times and can have air in there.

I would get the exh flap coded out and change the evap things near the drivers headlight that click. They get gloged up and can cause the car to run weird like a soft limp mode.

 

yeah my purge valve solenoid / evap solenoid (it’s all one part) had failed and I made 100 less whp with misfires. It was extremely loud like a lifter tick

 

I built a 800whp mustang and the secondary lpfp was failing. It was only making 650 at the top end due to fuel starvation. Dropped in a new pump and made another 150whp. I’d just check pressure at the fuel rail during wot along with AFRs/ fuel trims. I don’t think the dyno is reading THAT low unless you have serious traction issues. Did you try any dyno pulls in 5th?

 

So in regard to heat exchangers the consequences of bad bleed would be high IAT temps. Which we had experienced before due to a failing pump. FIXED

The exhaust flap would throw a code.

Not sure if Evap is a big deal like in the previous gen. Bit will check

Our current state; We went full CATLESS DP’s and did a E30 mix. The car is not getting past the 540 whp. The car has been smoke tested twice up to 40psi. Wastegates have been checked.

At WOT the waste gates duty cycle goes as high as 75% the car is heavily retarding itself.

Our dyno run still is showing knock/detonation even with the E30 mix. We are thinking possibly bad turbos? Overspin causing excess heat and air.

 

my car barely made 420whp with knock and detonation (26 misfires in two months) now I’m making 612whp on 101 octane with modalworks intakes and zac dp. Failing evap/purge valve caused all of my issues. Throw a new one in.

 

If you are hitting a consistent HP number and not exceeding it even with alternative fuel, your tuner is most likely missing a torque limit. Doesn't matter what you do with timing/AFR/boost if the torque limits are left stock it will make stock power. There's a lot of torque limits in the MED17.7.5, if you get stuck please give me a call or email me at matt@hdtuning.net and I'll help you.

 

is the ticking from the solenoid and indication that it has failed? I know I’ve read it’s normal. Or is there a symptom other than the ticking that would give this diagnosis? Does it just get louder and is constant? Just purchased my w205 a week ago and I know it’s the solenoid making the sound, can feel it when touching it. Thought about replacing it just as preventive work.

 

My car was low on power in the higher gears... ---> 3 leaking injectors....

 

is this fixed? I’m having the same exact issues on my glc63 with DSM.