M157 AMG turbochargers successfully swapped onto C218 Mercedes CLS550 M278 4.7 liter V8

[Sticky]

The Mercedes M278 and M157 engines may differ in displacement but they are the same basic design. They actually share many commonalities. While the M278 is not an AMG engine the M157 is basically just an M278 engine on steroids.

The M278 has a bore and stroke of 92.9mm x 86mm and the M157 has a bore and stroke of 98.0mm x 90.5mm. The motors share the same basic block and obviously the same cylinder count.

Since the early days that the M278 went on the market in Mercedes 550 models people have wondered what M157 parts would transfer over if any. Well, wonder no more. A C218 CLS550 owner who goes by the name 'gardevski' on the forums swapped the M157 turbochargers onto his CLS550.

The result?

The car is prepared for the ECU tuning at the end of this week. The exhaust and turbochargers are installed and all fitted great. I can confirm that the turbochargers are direct swap with no additional or any other parts needed except the gaskets and o-rings (it's recommended to use new when changing or repairing turbocharger)

Will post dyno and photos of the exhaust and downpipes installation. Will keep you informed.

I have good news. The car was completed today and run 680hp on 91gas and 700+ on 93. I can tell you that this is a true beast. It's noting compared to the stock turbos.. Will prepare all the details tomorrow when i have more time including the dyno run and will let you all know more detail

The problem? He did not post the dyno run or details. We do not doubt he did it we just would like to see proof as well as information on who tuned the setup.

Suddenly the M278 looks like a Mercedes tuning value.

[Stevenh]

Who would have guessed that Mercedes would end up delivering one of the most interesting tuning platforms at this point? Simple things like swapping turbos from hotter models or full drivetrains from car A with a motor from car B... prettttty cool. Can we make it cheap next?

[Sticky]

Who would have guessed that Mercedes would end up delivering one of the most interesting tuning platforms at this point? Simple things like swapping turbos from hotter models or full drivetrains from car A with a motor from car B... prettttty cool. Can we make it cheap next?

The 550 models are a pretty good value namely used.

This swap is similar in a sense to swapping RS6/RS7 turbos to the S6/S7. Now if only some BMW tuner could figure out an S63 to N63 turbo manifold swap.

[Zeee_Q]

In that case, a hybrid turbo such as the Weistec W3 package should bolt on to the CLS 550 also. Guess we will finally find out how much that extra displacement in the M157 is helping.

[65AMG]

Don't want to be too pessimistic, because I am always open for direct swaps of original parts, because the parts themselves are proven.

But if you put more power on another engine, you should do a lot of research what parts are different in the engine itself. Normally AMG always make some "hidden" work in the engine to strengthen it for a higher output in the longrun, like special pistons or piston cooling, tweaked fuel pump, transmission and so on.

I wish you good luck with your projects!

[Sticky]

In that case, a hybrid turbo such as the Weistec W3 package should bolt on to the CLS 550 also. Guess we will finally find out how much that extra displacement in the M157 is helping.

This is a good point and it makes you wonder why no tuner simply sells their M157 turbos for the M278? I mean the development is done all they need is a tune and it's easy money.

It makes me think this is maybe not quite so easy.

[vdubpower]

can we get an analysis of how the 2 turbos differ, is there a major difference or was it just a compression thing, obviously the m157 is almost a liter larger which makes a difference but its not the same situation with rs7/s7 because both are 4.0

[Sticky]

can we get an analysis of how the 2 turbos differ, is there a major difference or was it just a compression thing, obviously the m157 is almost a liter larger which makes a difference but its not the same situation with rs7/s7 because both are 4.0

True.

I wish we had the breakdown of the specs for both...

[blowns4]

Gardevski's car looks very fast from the looks of this video

[JDScott]

Gardevski doesn’t give all the breakdowns in full detail on his build thread, but he does state the m278 is identical to m157 except smaller bore, smaller turbos (but 278 has a higher flowing turbo manifold as he states). He owns both cls63amg m157 and cls550 m278. He basically had to upgrade IC pump, heat exchangers, AMG fuel pumps, AMG brakes, and body kit for heat.) this is for the basic upgrade which many have done just the turbo swaps since he already took the risk and others with the m278 have seen massive dyno gains due to higher compression ratio. Still not an AMG vehicle by any means, but still very impressive motors. Very interesting build thread y’all should check out! He custom designed an entire new setup for both m157 and 278. He’s just now tuning the new setup and real world results he states will be posted with additional info. Definitely worth the read!

[Sticky]

Gardevski doesn’t give all the breakdowns in full detail on his build thread, but he does state the m278 is identical to m157 except smaller bore, smaller turbos (but 278 has a higher flowing turbo manifold as he states). He owns both cls63amg m157 and cls550 m278. He basically had to upgrade IC pump, heat exchangers, AMG fuel pumps, AMG brakes, and body kit for heat.) this is for the basic upgrade which many have done just the turbo swaps since he already took the risk and others with the m278 have seen massive dyno gains due to higher compression ratio. Still not an AMG vehicle by any means, but still very impressive motors. Very interesting build thread y’all should check out! He custom designed an entire new setup for both m157 and 278. He’s just now tuning the new setup and real world results he states will be posted with additional info. Definitely worth the read!

That's all true I just wonder why tuners don't offer turbo swap kits?

[JDScott]

If I had to guess, I would assume most tuners may be under the impression as many others that since the m278 isn’t an AMG stamped motor then it’s weaker. Granted this has been true for engines in the past, but it seems AMG didn’t really change the M157 much unlike their custom 6.3 monster. Also, they may think profitability would’ve been a factor since most who buy AMG are supposedly all about performance compared to their non amg counterparts. But hey, Gardevski has broken that chain and has innovated a completely new design with custom built charge pipes/intercoolers/intake system etc. Since he owns a large company he’s able to produce what he’s built with industrial level quality. So the tuning capability is about to change for a lot of people making for some very interesting projects for many in the future.

[Sticky]

If I had to guess, I would assume most tuners may be under the impression as many others that since the m278 isn’t an AMG stamped motor then it’s weaker. Granted this has been true for engines in the past, but it seems AMG didn’t really change the M157 much unlike their custom 6.3 monster. Also, they may think profitability would’ve been a factor since most who buy AMG are supposedly all about performance compared to their non amg counterparts. But hey, Gardevski has broken that chain and has innovated a completely new design with custom built charge pipes/intercoolers/intake system etc. Since he owns a large company he’s able to produce what he’s built with industrial level quality. So the tuning capability is about to change for a lot of people making for some very interesting projects for many in the future.

I'm surprised nobody is coming to market then with a swap kit since other tuners seem to be missing the ball.

PM me a link to take a look at what he has done.