M111 Larger Crankshaft Pulley

[EndPoint]

I own a w203 with the m111 e20 ml evo engine. I currently run a 23cm crankshaft pulley but I need more hp so im thinking of upgrading to a 24cm pulley. are there such pulleys available ?

 

[carat 3.6]

I think kleeman do an upgraded pulley, but I cant remember what size it is.

 

[EndPoint]

kleemann's size for w203 (m111.955) is of ~215mm while its pulley for the 2.3l m111 is 240mm! but i dont think that could fit my car because its inner diameter is different

 

[EndPoint]

if i find a 240mm pulley is it going to fit right in place or would i have to install a smaller waterpump pulley as well ?

 

[carat 3.6]

Not sure about the waterpump, but I think you would need to change the alternator pulley due to it being "geared up".

Have you thought of fitting a smaller pulley to the kompressor?

 

[EndPoint]

its basically the same thing, either larger crankshaft pulley or smaller s/c one. it's strange no one produces any smaller s/c pulleys for the m111 evo engine as there is no clutch on the kompressor any more. though, its easier to install an overdrive crank pulley than a smaller s/c.

 

[carat 3.6]

Maybe you could get a local machine shop to make what you need out of solid aluminium? Wont be cheap, but will be less expensive than the kleeman stuff.

 

[EndPoint]

I dont understand why kleemann and other big companies like carlsson etc state that installing a larger crankshaft pulley u need a idle pulley or a waterpump pulley as i have my 23cm crankshaft pulley installed with no issues of fitment

 

[mauno]

tension

 

[EndPoint]

u could easily use a larger v-belt

 

[mauno]

ratio of rotation?

 

[flango]

I dont understand why kleemann and other big companies like carlsson etc state that installing a larger crankshaft pulley u need a idle pulley or a waterpump pulley as i have my 23cm crankshaft pulley installed with no issues of fitment

ASP racing do underdrive (supercharger) and Overdrive (crank) pulleys in various diameters for your engine. Easy shipping from USA and they know their stuff. Just google them if what you want is not on the website, give them a call they will be able to help for sure, but you won't find anything in the UK, we have tried for years.

 

[EndPoint]

flanaia1 pal, from al the research I've done, ASP can do ANY pulley for u just as u order it! but the pulleys they currently make for these engines are no bigger than ~215mm in diameter. not so aggressive like kleemann and ck which are 230mm. The only bigger than 230 is HS's 250mm(!!!!) and that scares me a bit...

 

[flango]

flanaia1 pal, from al the research I've done, ASP can do ANY pulley for u just as u order it! but the pulleys they currently make for these engines are no bigger than ~215mm in diameter. not so aggressive like kleemann and ck which are 230mm. The only bigger than 230 is HS's 250mm(!!!!) and that scares me a bit...

ASP do 232mm pulleys but not sure on what engine, is not the easy way to change the charger pulley?

I have a Brabus smaller charger pulley on mine which came as part of the K1s tuning kit

 

[Dieselman]

Do these overdrive pulleys actually work over a wide rev range.
The reason I say that is because the supercharger efficiency drops dramatically as back pressure and charger speed builds.

It would be interesting to measure the effective flow rate before and after. In addition getting the stopwatch out might be interesting.
What happens to the fuelling when the MAF tops out?

 

[EndPoint]

s/c efficiency is affected only by the heat which is produced if u over-spin it

 

[Dieselman]

s/c efficiency is affected only by the heat which is produced if u over-spin it

The greater boost pressure will increase air temperature which will reduce efficiency.
The issue is will the additional boost compensate for the reduced efficiency?

Add to that the greater likelihood of pre-ignition, I'm not sure there will be any gain.

 

[EndPoint]

The greater boost pressure will increase air temperature which will reduce efficiency.
The issue is will the additional boost compensate for the reduced efficiency?

Add to that the greater likelihood of pre-ignition, I'm not sure there will be any gain.

This is gonna happen only if u spin the s/c over the maximum rpm the manufacturer suggests and use poor quality fuel.

 

[flango]

The greater boost pressure will increase air temperature which will reduce efficiency.
The issue is will the additional boost compensate for the reduced efficiency?

Add to that the greater likelihood of pre-ignition, I'm not sure there will be any gain.

I agree with all of the above but there is absolutely no point in fitting either overdrive or underdrive pulleys without fitting a bigger intercooler, as DM rightly points out if you don't then the increased temperature reduces efficiency and increases the likelyhood of pre det and you will probably find you have gone backwards in terms of power.

If you take care of the temp with a larger intercooler then on the 2.3 engine you end up with a net gain of 23bhp by using a smaller SC pulley.

 

[Dieselman]

This is gonna happen only if u spin the s/c over the maximum rpm the manufacturer suggests and use poor quality fuel.

As flania says, the increased pressure will increase air temperature so reduce density and may lead to less oxygen being ingested.