alan16828

I have a question regarding the superchargers used in 2002 C230K Coupe and 2003 C230K Coupe. I understand that the 2002 has a 2.3L engine while the 2003 has a 1.8L engine. Who makes the supercharger that is used in the 2002 C230K? And who makes the supercharger that is used in the 2003 C230K? Is there any major difference between the two? Thanks.

Outland

The 2002 uses the 2.3L M111 engine- same as the SLK230 and previous C230 sedans- It makes 192HP and 208ft-lbs of torque on 5 or 6(depends on who you ask) pounds of boost from an Eaton M45 Roots type Supercharger. One of the amazing things about the M111 is that there is decent torque just off idle, and from 2500-4800RPM, always 200 or more ft-lbs available. This makes it feel like a considerably larger engine.

The 2003 uses the all new 1.8L M271 engine- the C230K Coupe was its first application. Its also in the C230 Sedan, and the upcoming new SLK(supposedly making 200HP in the SLK). It makes 189 HP and 190ft-lbs of torque from supposedly 10 or 11 pounds of boost from a modified M45. By many accounts, that's the upper limit of boost from the M45.

FrankW

just a minor correction: C180, and C200k both use the new 1.8 engine, so the C230k really isn't the first application. 180 being n/a and 200 with less boost from the s/c.

bajaiman

I could be wrong but from where I live (Australia), all 4 cylinder W203 are using the same 1.8L engine. So 2003 C180K, C200K and C230K are all 1.8L supercharged with different level of boost/tuning.

trench

You are correct, sir. Well, for the 2003+ models, anyway.

The previous model years used motors with displacements indicated by the badging.

- BT

FrankW

wasn't that wat i said? oops, nevermind, should've said 180k not 180...

seen

yes they use the same engine, but not only the boost but the compression ratio is different (180k, 200k, 230k)

[s]

Lynn

The ECU software is different, too

gmabm

So is it possible to fit a 1.8L C230K ECU into a 1.8L C180K and resulting 193HP?

I'm not being a cheapstake but its just that this new 1.8L C230K is not available through my country authorised MB agent.

Lynn

No, that wouldn't work, because of the different boost levels and compression ratios.

moomeh

sorry, this may be the dumbest question asked since i know nothing about engines. can't we just changed the compression ratio and get more power?

gmabm

The boost is controllered by the ECU, different boost levels would effect different compression ratios in the cylinders.

Therefore I believe changing of ECU is able to increase the power from engine. Moreover the displacements or rather the entire block is the same.

But I have noticed that there's another mechanical aspect which is not quite the same between the models are its gearbox ratios (or just simply a different final drive).

Matt230K

Nope, boost is not controlled by the ECU. It's controlled by how fast the supercharger is spinning. You can only control boost with the ECU on a turbo.

Lynn

To change the compression ratio, you have to change the pistons. To do that, the engine must be removed and disassembled.

gmabm

If that is the case, changing of pistons are not sufficient, we might also need to upgrade the crankshaft, conrod (& cam maybe?).

gmabm

What about changing the pulley, does it helps to increase boost?

But would the C180K ECU able to handle the addition fuel feed of a higher boost?? :P

Matt230K

Yes, changing the pulley will increase boost. Myself and many others on this forum have done that already. Unfotunately, there are not any pulleys yet for the 1.8L engine, only for the 2.0 and 2.3L engines.

As for fuel, there are different fuel settings and these can be changed by the dealer, and it changes the air:fuel ratio under certain conditions.

Lynn

No, just the pistons need to be changed. Compression ratio can be changed by changing the shape of the top of the piston.

iczer34

Haven't been able to fully utilized the "supercharger" ... still breaking her in

gmabm

Is this controlled mechanically by regulators or electronically compensated by ECU?

gmabm

Really? That makes the conversion even more simpler now.

moomeh

would it be cheap to change the compression ratio then to get more out of a car?

Lynn

To change the pistons, the engine must be removed from the car and disassembled. The oil pan must be removed to get to the rod bolts, and the intake and exhaust manifolds must be removed. The the head is removed. The pistons are pushed out their cylinders. The pistons must be separated from the con rods by removing the wrist pins. Now install new rings on the new pistons. The reassemble the pistons, wrist pins and con rods. Using a ring compressor, slide the piston and rods down the cykinders. Using new rod bolts and bearings, the rods and rod bearing caps are reassembled to the crankshaft. The oil pan, head, manifolds etc are reassembled. The engine is reinstalled in the car. This is just a brief sysopsis of the process. It is much more complicated. It will not be cheap, and I don't think higher compression pistons are readily available. They will be $$$$.

Now we are ready to use the engine, right? Wrong. The ECU might need be remapped if you are still going to use 91 or 93 octane gas. The engine will be more prone to detonate with the higher compression, so the ECU will need to retard the ignition advance. To make sure, you will need to do several tuning sessions on a dyno. On the other hand, you could use $4 to $5 per gallon racing gasoline.

Now, the engine is ready to go. Enjoy the break in period.

Matt230K

I'm not sure about this. I assume it's mostly electronically controlled. I think this is another question for Lynn.

Lynn

It is all electronic.