S320 W220 Quick or Easy tune-ups.

Azer

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Hi All,

I come from the world of carb.'ed motorbikes and so have a rather limited knowledge of fuel injected petrol engines.
I have a 2001 Petrol S320 with the V6.

Just wondered if there was a quick and/or easy way to adjust the tuning. I'm not looking for huge increases in performance or economy.
Mainly interested to know which adjusters do what on the fuel pump.

Thanks
 

DSM10000

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The fuelling, injector timing etc is controlled by the ECU and feedback from numerous sensors.

You cannot just "tweak" settings anywhere to alter performance.
 

DSM10000

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With normally aspirated fuel injected engines there are very few power gains to be had by changing the mapping.

You might get some reasonable gains with cleaning up and opening ports in the head but the cost would be prohibitive.

If you want more performance then the only realistic answer is to buy a car with a larger more powerful engine.
 
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Azer

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With normally aspirated fuel injected engines there are very few power gains to be had by changing the mapping.

You might get some reasonable gains with cleaning up and opening ports in the head but the cost would be prohibitive.

If you want more performance then the only realistic answer is to buy a car with a larger more powerful engine.
I did have this suspicion, just wondered if perhaps the same pump was fitted to all the petrol engines on the S class and therefore I have the same job as the 500. Which had been de-tuned. Giving "somewhere to go" by adjusting something.
Just a thought.
I'm wasn't and still am not, a boy racer.

Thanks again.
 

DSM10000

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I did have this suspicion, just wondered if perhaps the same pump was fitted to all the petrol engines on the S class and therefore I have the same job as the 500. Which had been de-tuned. Giving "somewhere to go" by adjusting something.
Just a thought.
I'm wasn't and still am not, a boy racer.

Thanks again.
The fuel pump isn't the arbiter of performance..

Unsure of what you are used to working on but fuel pumps are not usually adjustable but even if they were the injection timing, injection duration, ignition timing, camshaft phasing etc etc control the performance. 👍
 
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Azer

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Unsure of what you are used to working on but fuel pumps are not usually adjustable but even if they were the injection timing, injection duration, ignition timing, camshaft phasing etc etc control the performance. 👍

Motorbikes with carbs.
I was equating the pump and it's pressure settings with the jets in carbs.
1 or 2 sizes up on the main jets gives slightly better acceleration.

I don't have loads of experience with any of this stuff. Nor do I claim to be well informed. I just find it interesting.
 

DSM10000

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Motorbikes with carbs.
I was equating the pump and it's pressure settings with the jets in carbs.
1 or 2 sizes up on the main jets gives slightly better acceleration.

I don't have loads of experience with any of this stuff. Nor do I claim to be well informed. I just find it interesting.
The engine ECU controls everything.

If you increase the fuel pressure then it will either be regulated down or throw an error code.

A carburetor setup has no active feedback mechanism (as far as I know)

A modern engine has many sensors to help keep emissions in check and to monitor various parameters to give optimal performance.

There are Oxygen sensors in the exhaust that provide data to the ECU to optimise fuel injection, timing etc etc.

A Mass air flow meter on the induction side to measure air flow into the engine which is then used to calculate the optimum amount of fuel to be injected with the optimum ignition timing etc and all of these parameters are adjusted automatically depending on load, temperature etc.

The days of bolting on a pair of twin choke large bore Weber or Dellorto carbs and free flowing exhaust etc are long gone.

Tuning for extras power can be done but is usually far easier to achieve with forced induction engines where the engine map is altered to give more fuel flow, higher boost pressure, modified ignition maps and so on. 👍
 

Bellow

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Motorbikes with carbs.
I was equating the pump and it's pressure settings with the jets in carbs.
1 or 2 sizes up on the main jets gives slightly better acceleration.
All of that is covered by the ECU. It knows when to go rich (supress detonation) and when it can run leaner - from all the sensors. All you have to do is keep the sensors up to snuff.
 
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Azer

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The engine ECU controls everything.

If you increase the fuel pressure then it will either be regulated down or throw an error code.

A carburetor setup has no active feedback mechanism (as far as I know)

A modern engine has many sensors to help keep emissions in check and to monitor various parameters to give optimal performance.

There are Oxygen sensors in the exhaust that provide data to the ECU to optimise fuel injection, timing etc etc.

A Mass air flow meter on the induction side to measure air flow into the engine which is then used to calculate the optimum amount of fuel to be injected with the optimum ignition timing etc and all of these parameters are adjusted automatically depending on load, temperature etc.

The days of bolting on a pair of twin choke large bore Weber or Dellorto carbs and free flowing exhaust etc are long gone.

Tuning for extras power can be done but is usually far easier to achieve with forced induction engines where the engine map is altered to give more fuel flow, higher boost pressure, modified ignition maps and so on. 👍
Thank you, m' learned friend.
 

Petrol Pete

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Azer , you like me ,probably remember when it was pretty easy to get noticeably more out of a Kawasaki Z1000J with nothing more than a decent 4 into one exhaust (weight saving alone !) and a few jet/needle position changes.

In the dim and distant past I fitted a Dynojet kit along with a free flow air filter to my Honda Fireblade (1st edition) and spent time balancing the carbs . I did a before and after Dyno run and just on the ride back to the dyno I could feel a massive difference in the power delivery and the dyno proved that the dip in the curve at the midrange - that they used to 'engineer in' to pass noise tests - was gone. The kit added sweet FA to the peak power.

As others have said , those days are gone on N/A engines . My own C55 AMG has an M113 5.4 V8 engine, your first thought would be Wow! I bet you can tune that thing up !

You can , but it's not worth it ,MB took the same engine and bolted a supercharger on it for an instant 100bhp , To get an extra 100bhp out of a N/A M113 would probably be impossible without wasting a whole lot of cash.

Enjoy it as it is :thumb:
 

DSM10000

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Thank you, m' learned friend.
You are welcome although learned is a little too high a compliment.

I know some theory of how modern ic engines work but don't ask me to fix then unless it is simple 😁😁😁👍
 

RickMM

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Azer , you like me ,probably remember when it was pretty easy to get noticeably more out of a Kawasaki Z1000J with nothing more than a decent 4 into one exhaust (weight saving alone !) and a few jet/needle position changes.
And by sheer coincidence I just happen to have a Z1000J... with a decent lightweight exhaust... and a few jet/needle position changes too !
That's my old original one from the 1980's in my sig picture.
 
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Azer

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Azer , you like me ,probably remember when it was pretty easy to get noticeably more out of a Kawasaki Z1000J with nothing more than a decent 4 into one exhaust (weight saving alone !) and a few jet/needle position changes.

In the dim and distant past I fitted a Dynojet kit along with a free flow air filter to my Honda Fireblade (1st edition) and spent time balancing the carbs . I did a before and after Dyno run and just on the ride back to the dyno I could feel a massive difference in the power delivery and the dyno proved that the dip in the curve at the midrange - that they used to 'engineer in' to pass noise tests - was gone. The kit added sweet FA to the peak power.

As others have said , those days are gone on N/A engines . My own C55 AMG has an M113 5.4 V8 engine, your first thought would be Wow! I bet you can tune that thing up !

You can , but it's not worth it ,MB took the same engine and bolted a supercharger on it for an instant 100bhp , To get an extra 100bhp out of a N/A M113 would probably be impossible without wasting a whole lot of cash.

Enjoy it as it is :thumb:
Oh Aye!
Never got up to the dizzy heights of 1000CC bikes.
Last I had was a Honda NT400.
What you mention there, is more or less what I did. Though I was/am too tight to actually pay someone to measure it on a rolling road/dyno.
I miss being able to pull carbs. apart and fiddle. I have been toying with the idea of buying another bike for a few years now. But that would be a 3rd vehicle for me.
 

DSM10000

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Oh Aye!
Never got up to the dizzy heights of 1000CC bikes.
Last I had was a Honda NT400.
What you mention there, is more or less what I did. Though I was/am too tight to actually pay someone to measure it on a rolling road/dyno.
I miss being able to pull carbs. apart and fiddle. I have been toying with the idea of buying another bike for a few years now. But that would be a 3rd vehicle for me.
That's why I bought an MX5. I can do the majority of things quite easily

Plug changes, brake discs, pads, brake fluid changes etc. Have also replaced all of the brake hoses and some of the suspension over the last couple of years.

When it comes to work on the E Class or Range Rover they go to a specialist.

Without a proper garage lift they are just large unwieldy to work on plus the need for manufacturers diagnostics. 👍👍
 

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