BMW 135i owner, now looking at 4.7L SL500 or 4L C63

Flyingsparks

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Hi all

Never owned a Mercedes but think I will soon :)

Apart from the SL500 being 2 seater and C63 4 seater, is there much else different between the two models?

The engines outputs in terms of HP and torque are both similar. It looks like the SL500 has the M278 engine, and the C63 has the M177 engine. Is one engine "better" or more reliable than the other..?

I'm coming from a BMW 135i N54 engine, which has plenty of reliability problems and during my ownership plenty of money thrown at it. Do either of the above AMG engines have any common problems?

I was also looking at a BMW M4 but want to try something else and to be honest I'm a bit fed up with the long list of engine problems that BMWs can have. I'm hoping it's different with AMG engines?

I'll most likely be looking at 2016 models. Any info or links to other websites/videos appreciated.

On another random note, does anyone know the reason why the SL500 4.7L engine isn't listed as an AMG engine on Wikipedia? 😅 Mercedes-AMG - Wikipedia
 
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AMGeed

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Welcome to the forum:thumb:
No contest...................go for the C63 with the 4lt Biturbo unless you really want a 2 seater. The performance is incredible with scope for much more with just a remap.
I haven't read of issues with either engine (M177 /M278)

Regarding the M278 engine, it was never fitted to any AMG model ,so won't be listed as an AMG engine.
 
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Flyingsparks

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Thanks guys :)

Both are biturbo, are they so different in performance? Apart from the SL500 engine drinking more I imagine..!

What engine is in the SL500 then!? There's no 4.7L engine listed on that wiki AMG page.

BMW engine numbers are way more simple..!

I see you've had a couple AMGs...how have you found them? Had to spend much/anything on repairs etc?
 

Lennox

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Two very different cars. SL is a big cruiser, and the AMG an amazing uber saloon.

What are you looking for?
 
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Flyingsparks

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If I choose the C63, it will be a 2 door (probably coupe).

Dimensions wise...looks like the SL500 is about 10cm wider, but the c63 about 14cm longer.

I find it interesting how you describe the SL500 as a big cruiser when it's supposed to be a sports car..isn't it? 😅
 

Bobby Dazzler

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If I choose the C63, it will be a 2 door (probably coupe).

Dimensions wise...looks like the SL500 is about 10cm wider, but the c63 about 14cm longer.

I find it interesting how you describe the SL500 as a big cruiser when it's supposed to be a sports car..isn't it? 😅
Welcome to MBClub. You have picked two fantastic cars, I’m sure you would be delighted with both, however the driving experience is worlds apart.

If being generous then the SL500 could be described as sporty, although this is mostly because of the perception of what a 2-seat Roadster “must be” rather than the driving dynamics. @Lennox describes it perfectly, it’s really a relaxed cruiser.

The SLS AMG and AMG GT were intended to be the more sporting cars in that generation of the Mercedes range, although SLs are all quick, and the SL63 AMG is properly quick, and adds a sharper edge to the cruiser feel.
 

Bobby Dazzler

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What engine is in the SL500 then!? There's no 4.7L engine listed on that wiki AMG page.
As @AMGeed suggests, the SL500 is not an AMG model, and the M278 wasn’t fitted to any AMG models, and so it’s not listed as an AMG engine. It was fitted to a variety of Mercedes. Idea though, including the S-Class, E-Class, CLS-Class, (all 500 models).

In that generation of Mercedes, the AMG V8 engines were the W157 5.5 biturbo and the W177 4.0 biturbo (as fitted the C63 you’re interested in). There are ithe AMG V8, but those were the mainstream V8s for most AMG models, for most of the last decade.
 
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Flyingsparks

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Aha I'm so clueless on Mercs, thanks for that info.

Sounds like I had better go to a dealership and take a C63 on a test drive.

Am I correct that it's the M177 engine in the 4L biturbo C63? Do many people map these cars? Are there ever issues running higher boost? I assume Mercedes also void any engine approved used/extended warranty if you remap as well.
 

C240Sport97

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Try the SL500 too for completeness. It’s actually quite agile, handles surprisingly well and stonking quick. It’s all aluminium and other ‘exotic’ materials and thus lighter than you think.

chassis is mega stiff and I have never experienced scuttle shake.

and much rarer than a C63.
 

Bobby Dazzler

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Aha I'm so clueless on Mercs, thanks for that info.

Sounds like I had better go to a dealership and take a C63 on a test drive.

Am I correct that it's the M177 engine in the 4L biturbo C63? Do many people map these cars? Are there ever issues running higher boost? I assume Mercedes also void any engine approved used/extended warranty if you remap as well.
Yes the M177 is fitted to the current generation C63, and it’s tuned. Big name Mercedes-specialist tuners include Brabus, Renntech, Weistec, but there are plenty more. Google MSL Birmingham for a good idea of what’s possible.

There can be issues with tuned engines but I’m not aware of any specific to the M177, and yes you should expect you warranty to reject claims which are a result of tuning.
 
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Flyingsparks

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Thanks for confirming the engine. It's nice to google "M177 engine issues" and virtually nothing comes up. Try that with my BMW engine (N54) 😅 or even the M4 engine (S55), although they're definitely better than the N54.

How about things like turbos, injectors, fuel pump issues etc? No repeated issues? It sounds like a pretty bullet proof engine.

As expected with warranty/tuning. Tbh most dealerships try to blame the tune no matter what the cause.

What do you mean when you say "and it's tuned"?
 

bolidemichael

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Try the SL500 too for completeness. It’s actually quite agile, handles surprisingly well and stonking quick. It’s all aluminium and other ‘exotic’ materials and thus lighter than you think.

chassis is mega stiff and I have never experienced scuttle shake.

and much rarer than a C63.
I saw one the other day and was surprised as I'm accustomed to seeing an SL400 badge. I didn't realise that they released an SL500.
 

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Hey mate. I came from a highly tuned 135i N55 (which was bullet proof I have to say) to first the 6.2 litre C63 (w204) which I drove like hell for a couple of years and then the 4.0 litre biturbo w205 C63 (saloon) which I still have. So I've been on the same recent car journey as you. The w205 is without doubt, and easily, the best car I've ever owned. It is a beautiful drive and even nipping to the shops is an event. Make sure, whatever you do, you get the switchable exhaust option for the full snap crackle and pop. Good luck
 

Lennox

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If I choose the C63, it will be a 2 door (probably coupe).

Dimensions wise...looks like the SL500 is about 10cm wider, but the c63 about 14cm longer.

I find it interesting how you describe the SL500 as a big cruiser when it's supposed to be a sports car..isn't it? 😅
The SL? No not necessarily, the basic SL was always the older gents sporting GT convertible with the CL the coupe of the S class lux limo. And it just didn't sell. The in fact the current model looks to be on its way out with massive £25k discounts available off the bat.

The SL depending on the spec could be seen as a sports car but put it this way, have you seen an SL being used as a Nürburgring track toy?

Sounds like a carefully run in and then tuned by a respectable company (rolling roads only) C63 would be your car.

And re tuning that car, and absolutely do it, and it will be awesome. However, traction will be a big issue. I'm a 4 staunch wheel drive fan as I want power and traction. I do, however, have a 600bhp garage queen that is useless in anything but warm dry roads. And wouldn't know which way my baby AMG 300bhp+ toy went in the wet, cold.... Basically most days.
 
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RickMM

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Hey mate. I came from a highly tuned 135i N55 (which was bullet proof I have to say) to first the 6.2 litre C63 (w204) which I drove like hell for a couple of years and then the 4.0 litre biturbo w205 C63 (saloon) which I still have. So I've been on the same recent car journey as you. The w205 is without doubt, and easily, the best car I've ever owned. It is a beautiful drive and even nipping to the shops is an event. Make sure, whatever you do, you get the switchable exhaust option for the full snap crackle and pop. Good luck
I made exactly the same journey (N55 --> 6.2 --> C63 4.0 Biturbo) and totally agree with Iggu. The W205 (with the switchable exhaust) is far and away the best.
No reliability issues either.
 
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Flyingsparks

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Hey mate. I came from a highly tuned 135i N55 (which was bullet proof I have to say) to first the 6.2 litre C63 (w204) which I drove like hell for a couple of years and then the 4.0 litre biturbo w205 C63 (saloon) which I still have. So I've been on the same recent car journey as you. The w205 is without doubt, and easily, the best car I've ever owned. It is a beautiful drive and even nipping to the shops is an event. Make sure, whatever you do, you get the switchable exhaust option for the full snap crackle and pop. Good luck
Nice!! Hope you don't mind a few questions now..!

How did you justify the switch from the 6.2 to the 4L turbo? Or you just wanted a newer car?

How does the 4L turbo compare to your modded N55? (Performance, interior, ride comfort when cruising, handling when pushing it). I'm amazed you say your was bulletproof but then I guess you had an N55 and mine is N54.

Great to hear how much you love it. I'm getting excited now...this really feels like my next car :)

I've got to ask, and I know it's not why we get these cars, but occasionally I do long trips...how does the MPG of your AMG compare to your N55? Currently in my N54 I get about 22mpg combined and I imagine it'd be similar in the AMG.

Switchable exhaust? Is that the " AMG performance exhaust system" that I can see listed with cars on autotrader? How do I actually check for it when I inspect cars?


I made exactly the same journey (N55 --> 6.2 --> C63 4.0 Biturbo) and totally agree with Iggu. The W205 (with the switchable exhaust) is far and away the best.
No reliability issues either.
Amazing! Thanks for this Rick :)

Which other extras are must haves (or worth looking into)? I like the idea of the panoramic sunroof.


BTW - why are the 2 door versions about £5000 more than the 4 door versions? Is that just current ads on autotrader or that's just how it is..? (I'd be getting a 2 door!)

Thanks for all the info on the Roadster Lennox. All the ads on autotrader state AMG but it doesn't seem like it is actually an AMG...!? Bit strange.
 

flowrider

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The SL is several classes above the C class in quality so if you drive both the experience will be very different. A more relevant comparison IMO would be an SL500 against an S63 coupe.
 
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Flyingsparks

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Interesting to hear! Where would you notice these quality differences?

Please can someone also tell me what the "premium" designation means that I see with some C63 models?
 
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Flyingsparks

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Just looking into insurance now - any particular companies I should look at for these cars?
 

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