M156 vs m157 amg engines c63 e63 amg

[Steve84N]

I find it hard to look past the parasitic nature of how they fundamentally work.

Whilst this is true they always add more than they take away. All your other ancillaries take away power but they mean the engine can run for long periods.

I do love a supercharger and the V8 engine shape is made for them. Twin smaller parallel turbos work great too on modest engine capacities, like 3-4 litres. Very little lag and boost from low down.

Big power turbo builds aren't very nice to drive, at least with big power supercharged builds they remain driveable with smooth power delivery throughout the rev range.

 

[jimjamiejames]

Whilst this is true they always add more than they take away. All your other ancillaries take away power but they mean the engine can run for long periods.

I do love a supercharger and the V8 engine shape is made for them. Twin smaller parallel turbos work great too on modest engine capacities, like 3-4 litres. Very little lag and boost from low down.

Big power turbo builds aren't very nice to drive, at least with big power supercharged builds they remain driveable with smooth power delivery throughout the rev range.

In my view superchargers are old hat. They're heavy and high up so bad for center of gravity. They have more issues with heat. They put a lot of load on the crank to drive them so the engine has to be stronger to cope. The faster they spin the more power they take to drive and less effect at higher rpm. Oh and less fuel efficient.

I think the days of big turbo lag then huge boost are all but gone. Modern turbo cars don't really suffer that any more. variable geometry turbos or even electric hybrid turbos can provide smooth effective boost across a wide rpm range. I like sequential turbos although it's a bit of a nightmare plumbing wise.

Just my 2p

 

[Steve84N]

Lots of valid points there. I was mainly thinking about modified cars as factory stuff is all pretty tame.

You need a big capacity supercharger to avoid having to spin it too fast and cause heat issues, another reason they nestle nicely in a V8 or V6 for that matter. The centrifugal ones are lighter and work well on things like Honda engines in a Lotus Elise.

I was impressed by the C63 Biturbo I drove as it had little lag but top end the power tails off, the disadvantage to having two small responsive turbos. I've also tried a modified N54 in a BMW 335i and with a decat it spools very fast.

I've now got a 535i and it is a bit laggy due to how restrictive the factory cat is. As emissions regulations have ramped up it's hurt the performance of turbos. Yes you can use electric but then you're adding weight again...

Swings and roundabouts with some applications suiting one approach over the other imo.

 

[sgregory124]

I was impressed by the C63 Biturbo I drove as it had little lag but top end the power tails off, the disadvantage to having two small responsive turbos. I've also tried a modified N54 in a BMW 335i and with a decat it spools very fast.

Out of interest, at what speed/rpm range did you feel the power tailing off? I only ask because I was only thinking the other day, just how much power is available from say 80-130mph (as in, enough to push you back in your seat once you open the taps).

 

[Steve84N]

@sgregory124 speed I expect it keeps on going, I've never taken one over 100mph. Rpm from about 5k it goes a bit flat, still plenty of shove but not the same rate of change of acceleration. That 5-7krpm is exactly where the M156 zips to the redline (after a remap to release the standard latent potential).

You can see it on the chart here.

 

[E55BOF]

How about somebody posting the same chart for an M157 after MSL have 'released the latent potential'?

 

[sgregory124]

@sgregory124 speed I expect it keeps on going, I've never taken one over 100mph. Rpm from about 5k it goes a bit flat, still plenty of shove but not the same rate of change of acceleration. That 5-7krpm is exactly where the M156 zips to the redline (after a remap to release the standard latent potential).

You can see it on the chart here.

Ah fair enough, never seen a dyno chart from a standard car, so that's interesting to see.

 

[AMGeed]

How about somebody posting the same chart for an M157 after MSL have 'released the latent potential'?

My departed beast 572bhp and 593ftlb at the crank before remap.
After remap 666bhp and 775ft lbs. Amazing transformation.
MSL figs used for correction of 18%

 

[350cls]

I lean towards supercharging than turbos. Prefer the instant low down torque and the sound of the whine, reminds me of a jet fighter

Once a 156 man, always a 156 man
Dont be praising that Supercharged turbocharged junk

 

[E55BOF]

Once a 156 man, always a 156 man
Don't be praising that Supercharged turbocharged junk disappearing into the distance ahead of you

Fixed that for you. Yawn...

 

[350cls]

Fixed that for you. Yawn...

You do alot of yawning listening to that quite M157, it would make me nod off also .

 

[E55BOF]

As opposed to an M156 - nice, but not quite an M157?

 

[AMGeed]

As opposed to an M156 - nice, but not quite an M157?

Don't rise to the man child Dennis.
He is just trolling as usual.

 

[E55BOF]

So am I...

 

[Steve84N]

There's often a lot of capping turbo torque from a manufacturer, which is obvious on so many charts.

Here's the equivalent chart for an M156 in a C63 showing the artificially restrained power by limited throttle opening. The difference is as noticeable as remapping a turbo car from behind the wheel.

 

[E55BOF]

We've come a long way from simply replacing the carburettor tops on some big bikes to allow the slides to raise fully at full throttle.

 

[badgx]

Once a 156 man, always a 156 man
Dont be praising that Supercharged turbocharged junk

She's an old gal and i love her to pieces. Need some money please for a Weistec I can build it myself.

 

[E55BOF]

She's an old gal and i love her to pieces. Need some money please for a Weistec I can build it myself.

Respect. I can strip and rebuild an engine, and not have any important parts left over, but I wouldn't tackle something like that these days.

 

[350cls]

She's an old gal and i love her to pieces. Need some money please for a Weistec I can build it myself.

View attachment 132511

That's a cracking looking engine. Leave it as was originally intended, it didn't win awards for nothing . Even though it was in the 50's. When some of these 157 past owners were young men

 

[Steve84N]

We've come a long way from simply replacing the carburettor tops on some big bikes to allow the slides to raise fully at full throttle.

Have we? The same thing is essentially happening via electronics...