MJ, go away and think about that - you know better than type that.
M271 supercharger type, screw or roots
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MJ, go away and think about that - you know better than type that.
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The M271 engine started it's service life as a 1.8L supercharged unit, with 3 levels of tune.
Later in life there was also a 1.6L variant (which will probably be of little interest to you).
The supercharger was dropped in favour of a turbocharger. The latter CGI (strafified Charged Gasoline Injection) engines all have turbo chargers instead of supercharges.
So the C230 Kompressor will have a 1.8L M271 supercharged engine producing 201bhp.
The C250 CGI will have a 1.8L M271 turbocharged engine producing 201bhp.
You could get one of those as your starting point.
Later in life there was also a 1.6L variant (which will probably be of little interest to you).
The supercharger was dropped in favour of a turbocharger. The latter CGI (strafified Charged Gasoline Injection) engines all have turbo chargers instead of supercharges.
So the C230 Kompressor will have a 1.8L M271 supercharged engine producing 201bhp.
The C250 CGI will have a 1.8L M271 turbocharged engine producing 201bhp.
You could get one of those as your starting point.
Smart is turbo so no power from the crankshaft to realise its boost.
For mechanical superchargers I think the assumed power draw is circa 25% of crank hp. Which means that it is internally stressed higher than a TC motor as the actual power generated within is some 30% greater than appears at the crank.
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Stocious
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Is there a N/A version of the 1.8 M271
Cheap cam combo a they usually have higher lift , the diameter of the follower determins how aggressive you can go with cams, especially with a shin over bucket design, just to put it out there
Cheap cam combo a they usually have higher lift , the diameter of the follower determins how aggressive you can go with cams, especially with a shin over bucket design, just to put it out there
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I know that there are AMG Mitsubishi’s before they were bought by Mercedes-AMG
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The M271 has some design elements that Mercedes picked-up from Mitsubishi during previous joint work on engine projects.
But the M271 is not a 'Mitsubishi engine' as some put it.
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Not as far as I am aware. Maybe as prototype, I don't know, but the first Mercedes cars that had the M271 engine (in 2002/2003) where all supercharged.
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Would it be reasonable to think that the head flows well as standard,
It’s above par with to 20vt VAG unit
Adding 25% brings crank hp to 205hp on mine if I did sums right correct me if I’m wrong?
That’s a nice number but if correct the 230k engine is highly stressed at 251hp crank
Or
There a very stout engine, maybe heavy internals considering the 6k redline, that’s modern diesel ballpark!
Rev limiter can be removed , but I’d like to see a dyno graph first, but boost did hold till redline!
That may be something for me to explore ?
A 500 rpm bump, as long as it was in comfort mode it’d be safe, unless the rev limiter can be raised not just removed.
Whole different set of possibilities without needing to acquire and fit new engine as of yet
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And just for fun I’m holding an ACE, but that’s yet to be disclosed 
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Excuse the word crank in the above post, potential may suit better
Not really - it's a 2valve/cyl set-up but with small (circa 65mm) bore and twin plugs its detonation threshold will be relatively high. It's all about low down torque.
The 75hp (80hp in Roadster form) uses a bigger turbo and different cam. They also run shorter upper three gear ratios.
It’s above par with to 20vt VAG unit
Adding 25% brings crank hp to 205hp on mine if I did sums right correct me if I’m wrong?
That’s a nice number but if correct the 230k engine is highly stressed at 251hp crank
Or
There a very stout engine, maybe heavy internals considering the 6k redline, that’s modern diesel ballpark!
Rev limiter can be removed , but I’d like to see a dyno graph first, but boost did hold till redline!
That may be something for me to explore ?
A 500 rpm bump, as long as it was in comfort mode it’d be safe, unless the rev limiter can be raised not just removed.
Whole different set of possibilities without needing to acquire and fit new engine as of yet
The way I see it is a SC motor with say 200hp at the flywheel will have to make around 250hp at the crank. 200hp to the flywheel, 50hp to drive the blower. That would be a generalisation based on typical boost values of say 0.5 to 0.75 bar. Higher boost would require more power, lower boost less power.
Very generalised as power that would be absorbed by the crank just to ingest air is no longer absorbed there so that figure should be subtracted from the blower work.
Around a third of fuel energy (about the same as flywheel hp) on a NA engine goes as heat to coolant and all pumping work - air included. The friction of all that is also accounted for there but it gets difficult trying ascribe particular values for each as they are so interconnected. Eg, the induction stroke absorbs energy (NA unit) just drawing air - but there's also piston and ring friction in that stroke. Put bluntly, one third of fuel energy is expended over three pumping strokes (on a 4 stroke) when everything is factored in (and the heat loss to coolant isn't as drastic as it first appears as much of it occurs too late in the cycle to be of any real use - unless you were intent on capturing the energy in the exhaust stream that is).
I suspect some diesel 'strength' finds its way to petrol engines.
And just for fun I’m holding an ACE, but that’s yet to be disclosed
I'm intrigued.....
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Displacement, the m271 thread says for F3 they were bored to 2000cc
Problems : cylinder head, I’m going by they had to use what they already had.
Head gasket
Custom pistons - not impossible
Use piston from another engine - example: Toyota pistons are used in a Audi S2 stroker, diesel block and crank = 300cc increase.
M271 engine has forged rods already
Shot peening can make them even more durable.
Anything is possible
I’d have to see cylinder head and measure piston block protrusion
Way way in the future but worth noting here.
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One of the engine centers near me keep stock of aftermarket pistons, must be for rallying, I’m sure the could answer/help with any questions/needs I have.
But not if I went there not sure of the process
Boyracers don’t fit with this, I know who to ask when time comes, plus there have been custom piston group buys on old forum, MAHLE are the best, noise and oil consumption wise,
Research and development
But not if I went there not sure of the process
Boyracers don’t fit with this, I know who to ask when time comes, plus there have been custom piston group buys on old forum, MAHLE are the best, noise and oil consumption wise,
Research and development
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Questions for the day, all worthy.
Does it have oil squirters/piston cooling?
Knowing that fuel/ign tables would have to be changed, how many if any knock sensors are present, BOSCH were using two in 1991?
Can a wideband o2 sensor still provide for a O/E ECU? Or do you have to run it independently?
Does it have oil squirters/piston cooling?
Knowing that fuel/ign tables would have to be changed, how many if any knock sensors are present, BOSCH were using two in 1991?
Can a wideband o2 sensor still provide for a O/E ECU? Or do you have to run it independently?
If you are referring to my smart - yes, it has oil squirters.
Smart has one. My SB Chevy has one - despite being a V8. It doubles as a coolant drain plug - seriously!
Can a wideband o2 sensor still provide for a O/E ECU? Or do you have to run it independently?
Don't know but the ECU for my LPG system (Chevy) can be configured for either type.
I fear you will spend a fortune (in money and time) reinventing the wheel.
Here's my take on how to engage with engines.
1) Make the best of what you have by small acts of fettling. Eg, the throttle response and speed of automated gearchanges on a smart is enormously improved by the simple expedient of smoothing out the moulding frazes in the plastic induction pipes. Fettling, which doesn't take the engine far from its design point but improves it in ways the factory didn't have time for. The factory will have arrived at the best compromises for its intended role. Move too far in one direction and inevitably one or more compromises will become less favourable.
2)Decide on a desired power output and achieve it by the simplest, cheapest most economical, easily maintainable, and reliable route. Eg, if I was chasing 260hp - Chevy SB. By the time you have taken a 2.0 litre four cylinder unit to 260hp it is as bulky, heavy, and nearly as gutsy on fuel as a SBC.
Variations on the theme are sourcing a more powerful engine known to fit the chassis (easy with MB's V6 and V8 offerings) or just buy the complete car (assuming a good example can be found).
3)Embark on a project to develop some new concept. Done as proof of concept (long term) reliability isn't a concern but it will soak up cash and time (but the expectation is that it would return that investment and more if made commercially successful).
What I won't do is expend that level of resource retreading old ground (even with alternatively sourced components). Because, the required power is already available elsewhere, and, soon enough something will appear within your grasp with the desired power and characteristics and you are left with a pile of expensive parts on a work bench and no real use for them or prospect for resale. The vehicle as intended recipient may no longer be viable - or desired by the time the engine is ready.
Only to break new ground would I embark on such an involved project.
Your reasons are known to you but if you are as outlined chasing the most power from the block in front of you just for the challenge - I'd advise against it. The challenge wanes when the same can be bought off the shelf for a fraction of the cost - and can be deployed and enjoyed much sooner. Only my opinion.
