Modding a naturally aspirated S55 Engine - thoughts?
I am actually very happy with the "seat of the pants" feel of my S55, I think it pulls pretty strongly. I've driven various newer AMG's, (S55k, SL65, C63, etc) and while obviously they are faster, in lower speed driving I did not feel a night and day difference, just a mid-day to evening difference. (haha
) Anyway - I'd like to possibly mod it in the future for a bit stronger performance, regardless - as I think I can get a bit more out of it.
So I've done some research, and while I have not really seen many people mod this NA S55, some work has been done to the CLK55, E55 W210, etc - which is the same engine.
So what can I do, and how much power can I realistically gain from the stock 354hp, 391lbs of torque it currently has?
Here is what I think, let me know if my gain estimates are off:
Headers (Like Kleeman or Evosport) Can I get at least 20hp/tq from these?
Pulleys (Should give me around 11hp gain?) My engine can take upgraded pulleys correct?
ECU - Another 15-20hp gain?
So with those above mods, can I realistic gain close to 40/50hp? Or is that too optimistic and I'd be around 30hp total with all of those?
Any other mod that is reasonable and would get me gains? I don't want to supercharge, I know that's an option, but I just want a little more lively performance out of it and nothing mind boggling.
Thanks!




I am actually very happy with the "seat of the pants" feel of my S55, I think it pulls pretty strongly. I've driven various newer AMG's, (S55k, SL65, C63, etc) and while obviously they are faster, in lower speed driving I did not feel a night and day difference, just a mid-day to evening difference. (haha
) Anyway - I'd like to possibly mod it in the future for a bit stronger performance, regardless - as I think I can get a bit more out of it.
So I've done some research, and while I have not really seen many people mod this NA S55, some work has been done to the CLK55, E55 W210, etc - which is the same engine.
So what can I do, and how much power can I realistically gain from the stock 354hp, 391lbs of torque it currently has?
Here is what I think, let me know if my gain estimates are off:
Headers (Like Kleeman or Evosport) Can I get at least 20hp/tq from these?
Pulleys (Should give me around 11hp gain?) My engine can take upgraded pulleys correct?
ECU - Another 15-20hp gain?
So with those above mods, can I realistic gain close to 40/50hp? Or is that too optimistic and I'd be around 30hp total with all of those?
Any other mod that is reasonable and would get me gains? I don't want to supercharge, I know that's an option, but I just want a little more lively performance out of it and nothing mind boggling.
Thanks!
If you like your car and will be happy with just a little extra, go for it. Maybe get AMS shorty headers to save a but cash.
But that's just my .02
I love my s 500 and know won't be getting anything next two years, so I'm thinking of doing all same as you mentioned and it will be plenty for me.
I'm not sure I would spend all this money.
I'd talk to Jeremy at OE Tuning and see if he can do a tune for you. You'll get some more power, better throttle response, and the cost should be reasonable.
But definitely take a look at your other options too, and if you can afford doing other mods then go on ahead with it. In the end it's your car not ours!
In regards to tune, you should definitely try contacting OE Tuning! They make great power and they're also very reliable. My car can vouch for that!
Good luck to you and I'm sure what ever you end up doing to your car, it will definitely put a smile on your face!
Trending Topics
So if he does manage to spend all that time finding a vendor that sells that part, good luck making sure they even have that part readily available. We're talking about an 11 yr old aftermarket headers here... So the next thing would be getting one off headers made which would most likely cost you more than an entire custom Primary-Catback exhaust.
Just coming from experience, never buy headers unless you are 100% sure the quality is there, and the gains out weigh the price. Headers are not as easily accessible compared to a Prim Cat back so if you need to make changes to the headers or if problems occur... its a pain to get them checked and taken out of the car.
If you don't mind spending the money, then you'll be in my shoes. I ended up getting a very re-known local shop to make long tubes for my car. I mean sure... vendors make e55, cls55, sl55, etc.. headers.. but just because its the same engine doesn't been it'll fit because non of them fit in my s55 only because the clearance issues are completely different in each platform. So just a heads up! Don't want you to buy a set of headers that are for the same engine but in return it ends up sitting in your garage because you can't get them installed!
Last edited by ShangoAshe; Feb 12, 2011 at 02:16 PM.
The Best of Mercedes & AMG
This is all your personal choice, but regardless... If you want to mod, ECU FLASH is the way to go! I really do suggest you contact OE Tuning as I have previously stated, they are one of the best!
Also, only do the Primary Cat back if you're craving for a more beasty sound and if you don't mind spending the money... if not, an ECU flash will definitely be sufficient! so yah good luck bud
1.) Does the ECU tuning affect that? i.e should I get the exhaust mod first, and the ECU tuning is based on that, or is the ECU tuning just based on other things and that would not affect anything?
2.) You mention primary cat back - now what is the best exhaust mod for the price, that will give me some more performance, and make the car sound better? (Not overkill) And how much would this exhaust mod typically cost with labor/parts?
1.) Does the ECU tuning affect that? i.e should I get the exhaust mod first, and the ECU tuning is based on that, or is the ECU tuning just based on other things and that would not affect anything?
2.) You mention primary cat back - now what is the best exhaust mod for the price, that will give me some more performance, and make the car sound better? (Not overkill) And how much would this exhaust mod typically cost with labor/parts?
1.) Well there are two kinds of ECU tuning you can get. You can just get the basic "FLASH" which is the most optimal for a stock car and usually the most inexpensive. (or) a dyno/street ECU tune which will cost more but the tuner will accomadate with your car's mods.
If you do plan on doing a Prim-Cat back system you probably don't need to go for an actual dyno/street tune because it really does not effect the car's performance (that) much. So overall your car is still pretty much stock, IMO there is no use of paying more for a more defined tune!
2.) Pending on what you're looking for. If you're looking for just a slight increase in volume a resonator delete would be sufficient. That'll probably cost you parts w/labor around $200...
If you're looking for a little more power but without the overkill volume then delete both the secondary cats & resonators. The Prim and Secondary Cats create most of the restriction in the exhaust system so deleting them will definitely give you power. But if you delete both, your car will sound insanely loud (like mine) BUT in turn, gives you a very good exhaust with no restrictions...
Don't quote me on this; but, a Secondary Cat & Resonator removal would most likely cost you around $700 or so because it is more time consuming with the issue of taking apart your exhaust! Keep in mind, pending on where you live the actual steel you use is also very important. I live in the North West and we're famous for rain, and the occasional snow! So I opted for T304 Stainless for my entire exhaust system. Some people might think its overkill but if you live in a wet region, the last thing you want to worry about is a rusting exhaust with holes/leaks from mild steel! (Which is a LOT cheaper to buy)
Hope that answered your questions!
Last edited by ShangoAshe; Feb 12, 2011 at 06:36 PM.
1.) Does the ECU tuning affect that? i.e should I get the exhaust mod first, and the ECU tuning is based on that, or is the ECU tuning just based on other things and that would not affect anything?
2.) You mention primary cat back - now what is the best exhaust mod for the price, that will give me some more performance, and make the car sound better? (Not overkill) And how much would this exhaust mod typically cost with labor/parts?

My whole entire exh was custom built except for the Kleeman headers that I have. Look at some of the pics of the headers made for the different models,W209CLK55,W211E55 and trust me it's not a hard thing to figure out.
If room is an issue on your car as far as headers are concerned you can go from the cats back which will make a difference. Headers will add more but a primary cat back system will be effective. I have tried them all. Plus the fact I see you live in NY so if you need more help you can pm me. Alot of guys I know have all kinds of custom setups from turbocharged C36's to my friend Jody (GodSpeedV12) who has just dropped a CL600 TT V12 into his 2k5 E55k. Then there is my C43 with the 5.4L motor.
Read in the E55 W211 forums and you will read all about his car. NY is full of guys that can make what you want work. I personally know quite a few by the way.






