Mercedes-Benz Forum banner

1 - 20 of 84 Posts

·
Registered
W107 W113
Joined
·
1,309 Posts
Discussion Starter #1 (Edited)
Hello:

I was wondering why the 560 SL engine power rating is so much lower than the european 560 engines.

The first low compression 560 Euros with catalitic converters had 252 PS, while the high CR (10:1) reach 279 PS.

Where are the differences?

Camshaft, DME, injectors?

Just curious.
 

·
It Is What It Is, Dude
Joined
·
22,839 Posts
.



What was the compression ratio for NA production 5.6L engines? No where near ten to one, that's for certain.
 

·
One of the BW Old Guard/R129, W204 Moderator
1997 SL500- 40th Anniversary
Joined
·
7,150 Posts
Hello:

I was wondering why the 560 SL engine power rating is so much lower than the european 560 engines....
Can you say, Eee Pee Aaa,? Smogged to death, is my opinion.

CR is 9.x:1, but can't remember exactly. 9.4 sticks in my mind, for some reason.

Edit...
From Piel De Toro: http://www.pruebas.pieldetoro.net/web/MERCEDES/dossier.php?ID=5

560SL (Sólo para el mercado USA)
Producción: Septiembre de 1985 a Agosto de 1989.
Nº de ejemplares construidos: 49.347
Motor: M117, 8 cilindros en V.
Diámetro/Carrera: 96,5x94,8 mm.
Cilindrada: 5.547 cc
Relación de compresión: 9,0:1.
Alimentación: Inyección Bosch CIS-E.
Potencia: 227 CV SAE a 4.750 rpm.
Par Máximo: 28,4 mkg a 3.250 rpm.
Transmisión: Cambio standard automático de 4 velocidades: 1ª-3,68:1, 2ª-2,41:1, 3ª-1,44:1, 4ª-1,00:1.
Grupo cónico: 2,47:1.
Suspensión: Independiente a las 4 ruedas, delantera con trapecios transversales, muelles, amortiguadores y estabilizadora, trasera con brazos oscilantes, amortiguadores y estabilizadora. Opcionalmente control de nivel hidroneumático.
Dirección: Servo asistida de recirculación de bolas y diámetro de giro de 11,5 m.
Frenos: Circuito hidráulico doble. Discos a las 4 ruedas y ventilados los delanteros. ABS.
Neumáticos: 205/65 VR 15.
Dimensiones: Largo 4,580 m., Ancho 1,790 m., Alto 1,290 m. Batalla 2,455 m., Peso 1.715 Kgr .
Velocidad Máxima: 137 Millas/h.
Aceleración: 8,0 Seg. 0/60 Millas/h.
Consumo: de 14 a 17 litros/60 Millas.
Tanque de combustible: 90 litros.
 

·
Registered
1986 560 SL
Joined
·
7,300 Posts
Can you say, Eee Pee Aaa,? Smogged to death, is my opinion.
Fast forward 25 years ..... modern car engines are making undreamed-of HP numbers while emitting exhaust that is actually cleaner than ambient air in many locales. And achieving decent mileage too.
Magic!
 

·
One of the BW Old Guard/R129, W204 Moderator
1997 SL500- 40th Anniversary
Joined
·
7,150 Posts
Fast forward 25 years ..... modern car engines are making undreamed-of HP numbers while emitting exhaust that is actually cleaner than ambient air in many locales. And achieving decent mileage too.
Magic!
Ah, yes... The influence of CAFE at work. Could we have had the same in the 80's?
Of course, consumer demand does influence manu to a certain extent, C'Nest Pas? Maybe, but it was a lot easier to just band-aid the situation, rather than spend the research dollars until "forced" to.

Yeah, I know... I'm jaded a bit.
 

·
Registered
1986 560 SL
Joined
·
7,300 Posts
Ah, yes... The influence of CAFE at work. Could we have had the same in the 80's?
Of course, consumer demand does influence manu to a certain extent, C'Nest Pas? Maybe, but it was a lot easier to just band-aid the situation, rather than spend the research dollars until "forced" to.

Yeah, I know... I'm jaded a bit.
Funny how the impossible becomes possible, with the proper incentives.
Remember when airbags too were said to be impractical? Now some cars have seven or so.
 

·
One of the BW Old Guard/R129, W204 Moderator
1997 SL500- 40th Anniversary
Joined
·
7,150 Posts
Funny how the impossible becomes possible, with the proper incentives.
Remember when airbags too were said to be impractical? Now some cars have seven or so.
Yep!

On fuel economy, my LS430 recently, returned 29.7mpg on a trip to Mobile, at 60mph. I drove at 60 just to see the affect on fuel consumption. At 70, it returned 24.6... This is a 290HP V8 (320 ftlbs), mind you. Total fuel economy, since the last reset a couple of years ago is just north of 22mpg (mostly short city driving, with occasional road trips)...

Of course, all the numbers are generated from the on-board computer and can be suspect.
 

·
Registered
1978 450 SLC
Joined
·
47 Posts
I'm pretty sure it's the combination of the compression ratio, possibly cam profile, and the exhaust. The euro version of the 450s that I've been looking at don't have cats and the addition of them in the US version caused an extreme decrease in power.

Is the combustion chamber in the head on these engines along with the 450?? If so you can just shave off some of the head to bump the compression back up. A machine shop can do that fast and it's super easy to do. Slap it back on and you should be good to go. I wouldn't think that these engines would have the valves anywhere close to the pistons to be worrying about them slapping each other with stock cams.

I'll probably be making a new exhaust for my 450. Not sure about the exhaust manifold. I finally got to see one and the stock US 450 exhaust manifold is HORRIBLE. It's way to small and it's just designed horrible.
 

·
Registered
500SLC #2624. Black on Black.
Joined
·
5,120 Posts
I'm pretty sure it's the combination of the compression ratio, possibly cam profile, and the exhaust. The euro version of the 450s that I've been looking at don't have cats and the addition of them in the US version caused an extreme decrease in power.

Is the combustion chamber in the head on these engines along with the 450?? If so you can just shave off some of the head to bump the compression back up. A machine shop can do that fast and it's super easy to do. Slap it back on and you should be good to go. I wouldn't think that these engines would have the valves anywhere close to the pistons to be worrying about them slapping each other with stock cams.

I'll probably be making a new exhaust for my 450. Not sure about the exhaust manifold. I finally got to see one and the stock US 450 exhaust manifold is HORRIBLE. It's way to small and it's just designed horrible.
D-Bat, once again, get some Tri-Y's for your 450.
 

·
Registered
1978 450 SLC
Joined
·
47 Posts
I am going to once I find a set somewhere. I haven't seen any pics yet of a set of tri-y's. I'm wondering how big the exit is compared to the size of the ports.
 

·
Registered
1978 450 SLC
Joined
·
47 Posts
Took a loot through ebay.de and didn't find any. Just full engines. Maybe I didn't search with the right german words but even so. Buying those on there would be at least a hundred or two plus shipping. I think I'd rather fab up a tri-y with a cross/x-pipe somewhere down the line. Main thing that would stop me from doing that is the exhaust manifold flange which I can get a CNC shop to cut me out one. Toss on some V-Band flanges and call it a day, or a few days rather to get the whole thing done. :p

Making a full header makes me want to put some turbos onto the end of them though. :p Ya know what I mean?
 

·
Registered
500SLC #2624. Black on Black.
Joined
·
5,120 Posts
I am going to once I find a set somewhere. I haven't seen any pics yet of a set of tri-y's. I'm wondering how big the exit is compared to the size of the ports.
They were good for 380HP when M-B built the 500SL rally cars. (yes, 500SL, not SLC).

All LHD 500SL's should have them, find someone wrecking one, or just buy the parts from the classic centre or parts.com.
 

·
Registered
560SL,380SL
Joined
·
4,012 Posts
You definitely can't shave these heads to any point where it would help much, the manual gives a limit. Also, shaving the heads brings up a whole slew of geometrical problems - the shims (or possibly even shortening the valve stems!), the timing chain gears have to be offset, the intake manifold might have to be built up or assembled (very risky) with two sets of gaskets - hopefully, the valves and pistons wont hit (higher C/R engines have pistons shaped and relieved differently), and then, there is the issue of the combustion chamber itself and it's new, possibly non-optimal configuration. The engine might actually start knocking even on premium, so then you have to back down the timing...which might put you back where you started in terms of power.
 

·
Premium Member
1972 280CE
Joined
·
4,198 Posts
My Friend David Poole of European Performance here in Dallas told me that he put a set of Tri-Y's on a 560SL and he said that it felt the front wheels were about to lift off when you punch the gas.

I've not seen the 560SL exhaust set up but if it's anything like a 560SEL, then I can believe it.

Bang for buck, it's probably the best way of freeing up power from your US spec 5.6 engine.
 

·
Registered
1978 450 SLC
Joined
·
47 Posts
Is most of your thoughts speculation on what "could" happen because I realize that stuff like that could happen but when shaving a head to raise compression one point it's not really that much they are taking off. I know on my VW motors that have timing chains they can be milled a few times without any problems with the timing chains on those. I'd like to have some numbers to push around if anybody has them on valve clearance. I highly doubt they put a radical cam with high lift in these motors. If shaving the head for one point makes them slap, then putting in a higher lift cam would do the same exact thing.

The manual probably gives a limit because it wants you to stay with in factory spec. If you are bumping up compression you are obviously going out of factory specifications. I don't think you'll see any manuals that say shaving the head is ok on any car to bump up the compression. I say to bump up the compression because as we all know shaving the head to resurface them is common practice when doing head work. Shaving off .030" to .040" is a decent amount but I some how doubt it'll make the difference for the intake manifold. Saving off .030" to .040" should get the increase in one point.
 

·
Registered
1999 Porsche 911 / 2013 ML350 / 2006 Mini Cooper S
Joined
·
671 Posts
About those tri-y headers: are they pretty much an Ebay item or can they be found through a parts dealer? There is a shop locally that could fabricate some custom headers for my 560SL, but the cost would be astronomical.

I did a search but it didn't get me anywhere. :eek:

Any feedback appreciated!! :thumbsup:
 

·
Registered
1978 450 SLC
Joined
·
47 Posts
I looked on ebay.de since it's an Euro item and I couldn't find them on ebay. If they are not readily available or cost a whole crap ton I'd like fab up a set and then make a welding jig incase anybody else wanted a set. Making a jig after the product is done is super easy.

Or if somebody let me borrow their 500sl exhaust manifolds I can just re-create those. :p
 
1 - 20 of 84 Posts
Top