😒 CONFIRMED: FACELIFT C63S HAVE SMALLER TURBOS
how the 2mm smaller FL turbos are better for performance and us enthusiasts?
Have you measured boost threshold and boost lag between the two? Have you torn down each turbo and compared all the components to confirm your theory that these are “next gen” turbos? The only reason for downsizing a turbo is to increase response, but you’re sacrificing power when you tune and increase the boost.
So I’ll take the extra 2mm and the 20-30 HP more I can get on my tuned PFL. For the folks staying stock, you won’t notice anything different.
Two posts ago the response couldn't be noticed, now it's the only discernable difference! Maybe they did it so those pesky new owners can't get as much power on a tune? U know, just to annoy them a bit.
In the UK facelift cars are having no trouble getting the same power as PFL cars after a tune.
Why wouldn't they improve on a 5yo design? The last aftermarket turbos i bought have, incorporating xona cartridges and next generation aero blades for improved performance, it's not exactly a massive surprise or wild assumption to make.
So how much cost did Mercedes save re-engineering, re-tooling, testing and manufacturing new turbo units, for what?
The most likely reason (going by years of dealing with manufacturing suppliers) is the turbo supplier has engineered new technology and incorporated it into their offerings, you see it's difficult to continue producing old stuff when they need to stay competitive outweighs the benefit. It's just normal lifecycle/obsolescence and with it comes better performance. If they didn't, Mercedes wouldn't keep using them. The only cost saving is dropping the production of old technology.
So your PFL turbos are obsolete. Sorry to have to have to break it to you.
So who cares if you have FL or PFL...for most considerations on a grand scheme they are the same generation of cars. So, who cares.
Last edited by tobeit; May 17, 2020 at 01:14 PM.
So who cares if you have FL or PFL...for most considerations on a grand scheme they are the same generation of cars. So, who cares.
Same thing happening to the FL R8 and imo it’s just a better car. Noise is an issue we’re just going to have to deal with aftermarket post 2020 models. That’s the new reality.
Last edited by elitex; May 17, 2020 at 01:33 PM.
So who cares if you have FL or PFL...for most considerations on a grand scheme they are the same generation of cars. So, who cares.
Actually I've just measured the thread thickness on the steering wheel stitching, the FL is 3 microns thinner, therefore the PFL is clearly better and more durable. Bloody Merc cost savings again..🤦♂️




https://youtu.be/7lLzG3K3psE
The Best of Mercedes & AMG
I bought my Coupe in 2016 the moment it was available to order and I’ve enjoyed every second of it. I laugh every time MB sends me an upsell letter trying to get me to trade in my car for one with an LCD screen for ONLY 30k!
Two posts ago the response couldn't be noticed, now it's the only discernable difference! Maybe they did it so those pesky new owners can't get as much power on a tune? U know, just to annoy them a bit.
In the UK facelift cars are having no trouble getting the same power as PFL cars after a tune.
Why wouldn't they improve on a 5yo design? The last aftermarket turbos i bought have, incorporating xona cartridges and next generation aero blades for improved performance, it's not exactly a massive surprise or wild assumption to make.
So how much cost did Mercedes save re-engineering, re-tooling, testing and manufacturing new turbo units, for what?
The most likely reason (going by years of dealing with manufacturing suppliers) is the turbo supplier has engineered new technology and incorporated it into their offerings, you see it's difficult to continue producing old stuff when they need to stay competitive outweighs the benefit. It's just normal lifecycle/obsolescence and with it comes better performance. If they didn't, Mercedes wouldn't keep using them. The only cost saving is dropping the production of old technology.
So your PFL turbos are obsolete. Sorry to have to have to break it to you.
Keep in mind, the OG post says 1.8mm in BOTH the compressor wheel AND the compressor housing itself. That is not adding efficiency, that’s taking power off the table when you start to push the turbos beyond the efficiency table.
And I’ve done my share of R&D with these turbos. If someone wants to send or donate a FL turbo, I’ll do the same measurements as I did here:
And here’s a set of stage 2 turbos with upgraded compressor and turbine wheels:
I’m happy to share my findings with this forum (unlike many others), so if someone wants to share all the dimensions of the FL turbo (inducer and exducer for compressor and turbine wheels), then we can actually have something of substance to discuss besides FL
vs PFL.
Last edited by AlexZTuned; May 17, 2020 at 04:02 PM.
I bought my Coupe in 2016 the moment it was available to order and I’ve enjoyed every second of it. I laugh every time MB sends me an upsell letter trying to get me to trade in my car for one with an LCD screen for ONLY 30k!




As for R34 owners, myself being a JDM junkie and growing up in that era, I can tell you those cars gave you a feel you just can't replicate in today's cars. You didn't have to worry about 1000 sensors that can go wrong, electronic gremlins once you're past the factory warranty, etc. It was everything you needed in a car (with a manual trans), and none of the stuff you didn't. And the car did whatever you told it to do, right or wrong. Made you a better/more careful/calculated driver too. I actually used to own an R34, and I can tell you, when I tracked a GTR (new gen), it felt like a BOAT, and sure, it did everything you wanted it to do, and it did it very well...no doubt, it was an amazing car. It accomplished nearly everything perfect. It simply forgot one central thing: The Driver. The driver's experience and feel of you being in actual control of the car vs 20 computers guiding your every move... You simply lost the connection to asphalt that old school gave you. So yea, newer isn't necessarily better (albeit it may mean faster).
I'm in the market for another C63S right now, and I'm specifically limiting my search to 17s and 18s, cuz I don't want a FL. Finances isn't a concern; if you gave me a FL, I'd sell it and get a PFL instead. Cuz that's my actual preference.But then again, I'm probably one of the older guys in this crowd (growing up in the 90s era of JDM sportscars), so while I value simplistic yet functional, many of the newer gen are all about the the new tech and gizmos, even if you'll never really use or need it.
Having said that, I won't be surprised at all if the W205 C63 ends up marking the end of an era...loud exhausts and big block motors, due to the new EU regulations. Might be worth holding onto your cars in the long run...
Last edited by FDNewbie; May 18, 2020 at 04:44 PM.
As for being a boat, it's the nimblest big car I've ever owned and belies it's size.
You said you don’t understand how people can justify the PFL with all the new fluff features added to the FL - again, you’re disregarding the majority of members on here that purchased PFL’s when they were still brand new. Why do you keep assuming the only people that own a PFL are second hand owners? I still have a factory warranty remaining through the end of the year on my 17’ Coupe.
In terms of visuals, both exterior and interior, I prefer the PFL. The changes are so minor and superficial (compared to other facelifts in the past) that there is nothing visually appealing to me about the FL. The Panamericana grill is cool, that’s about if. I could not care less if I had redundant mode selector controls on my steering wheel, or digital black slab to stare at. I hate the new FL headlights, maybe that’s just me - most people probably don’t even know the difference.
For what it’s worth, I’ve had my engine/trans/suspension updated multiple times - and just had the latest suspension software updated when I had my car in for service last week and every setting feels more compliant and better. The PFL has only gotten better and better over time.
You can keep the new 9 speed. I have a fundamental disagreement that you should not need 3rd gear to hit 60 mph if you have a twin turbo V8. I know it’s faster, yadda yadda yadda, but that new gear ratio is more suited for a 2.0L turbo than a twin turbo V8. The only cool thing about the 9 speed (assuming it can stay in one piece when tuned) is the possibility of swapping the E63S trans and front drive axles to do a 4 matic W205 C63 swap 😉





But MAN lol, i'm glad I have the PFL.
And that's great! We should all love our cars.
But I don't get why almost every PFL owner does everything they can to make their car look like a FL.
Might as well get a FL and fix the sound, rather than get a PFL and change everything about it.


