Is the 230 kompressor motor any good?
 

I am thinking of buying a slk. I see the slk versions have some features which are interesting. Are these motors well thought of? I resisted them at first not liking the complexity but now I tend to think the blowers are prolly pretty bulletproof.

They should be lighter than the v6...?

In general they are pretty solid engines, the supercharger isn't bulletproof at all - service life seems to be 130-180k miles and then the bearings start to make noise and it you ignore it for too long the complex rotor lobes will start interacting and then things really get interesting. Unfortunately the supercharger is switched on by an electro-magntic clutch that is also susceptible to wear and these often also have to be replaced. You're looking at approximately 2K for the supercharger and the clutch assembly.

Fuel economy is pretty decent, my C230 would return 30+ highway MPG. The biggest downside of this engine is its refinement..... of lack thereof. At higher rev ranges it actually puts of a nice supercharger whine and sounds pretty nice....... at lower RPM ranges my Kubota tractor puts it to shame in the refinement category.

Power output is also very good, around 190hp and there is zero supercharger lag.

In short crude but effective is how I'd describe the experience.

Thanks Tim! If you take it easy most of the time does the compressor rest?

If you're concerned about compressor wear, could you install a cutout switch for the e-m clutch?

As I recall the compressor engages at 2050 RPM, you'd have to be very easy with the throttle and keep the speeds < 30 mph to keep the compressor out of the game. Once engaged it doesn't disengage based upon engine load however there is a computer directed bypass valve that can vary the effective delivery of the compressor by short-circuting the input to the output. This basically permit "free-wheeling" operation when your just cruising down the road.

So in a sense if you're careful with the throttle you'll be rewarded with better economy - no big surprise there.

I'm sure you could, I'm guessing the check-engine light would come on in about 2 seconds. The ECU checks for a certain resistance through the clutch coil windings and it will trigger a CE light.

Of course a smart young man like yourself would invariably try to substitute a properly sized resistor to satisfy the resistance check. Of course that wouldn't work either because I'm sure you'd then confuse the ECU when it was expecting a certain level of boost at a particular throttle position. It would then assume (correctly) that there was some sort of problem with the supercharger and it would trigger a CE light. It may also do other things like restrict throttle inputs or fuel delivery. You'd have to check with the people that wrote the engine management software to know for sure.

And as a final 'nail in the coffin' for this idea you should also be aware that the supercharger also functions as an air-pump for the secondary air injection system. There are a series of switchover flaps and check valves that will direct supercharger output into the input air supply for the air injection system. Your mod would effectively disable the air pump and it would trigger a P0410 code.

I guess you could ignore the CE lights but its been my experience that trying to fool around with the parameters of modern engine management systems will bring unpredictable results.

YMMV.

From what I'm told, the older 2.0 engine is far more solid than the 1.8. Seems to be the norm at auction as well. I see lots of 2003 and newer 230 engine cars at the auction with engine problems.

Common theme with the older ones (2002 and older) is a worn sounding supercharger, which isn't the end of the world.

Why not go for the SLK320 V6? That would be my first choice of the bunch... well not really. R129 would be my first choice.

I am hoping to find one which will be competitive at the autocross course. I figured the 4 was prolly lighter and I saw it came with wider rims on the rear some years so am giving it some thought. My first feeling was to go for the 3.2 v6.

Honda S2000? Later Toyota MR2?

Of course the S2000 is always a nice option, and perhaps the MR2. I was perhaps dreaming that the slk equipped correctly might be competitive. I like its hard convertible top.

What is the failure mode of the supercharger clutch? On the 55K cars the electromagnetic clutch is also a common fault. On that engine it is the bearing in the clutch which generally fails. However it is possible to source a replacement bearing in the aftermarket and repair the clutch at minimal cost; no more than $100 for parts and machine shop services. Is a similar repair possible on the C230 supercharger clutch?

My Mercedes Guys tell that there are better choices unless you just want to mess with a supercharger.

They are kinda old school and would tell you that aluminum is iffy for blocks and heads, cast iron is the way to go.

Get an R53 Mini......

Very proven auto cross car

I prefer rear wheel drive.;)

Get a Miata then. The NA's are so simple yet effective why go with a bloated SLK that is going to puke its supercharger in short order.

I was all for RWD until I bought a MINI. It's a ton of fun and it really sticks to the corners