M111.975 Compression Ratio?

[Pagz]

Iv spent a fair amount of time attemtping to find the CR for my M111.975(M111 kompressor engine)

A while back i got a ratio of 8.8 from someone(maybe slammedc) can anybody find a document that states this ratio?...Ross?

Its likley im about to have new pistons made and there is a chance we may change the CR this time...but only if it seems alittle high...


Thanks all,
Paul

[xvvvz]

Engine 2,295-cc DOHC 16-valve inline-4, cast-iron cylinder block, alloy head.

Net power 185 hp @ 5,300 rpm

Net torque 200 lb-ft @ 2500-4800rpm

Compression ratio 8.8:1

Fuel requirement Premium unleaded, 91 pump octane.

Fuel and ignition systems ME 2.1 sequential multipoint fuel injection and ignition with antiknock control. Electronic throttle.

(Data directly from the Mercedes USA site for the 1999 C230K which has the M111.975 engine)

[Pagz]

Hey,thanks

Interesting!...that must be the US spec engine??...from all my googling im pretty sure the Euro spec is 192hp,and uses minimum 92 octane?...Im wondering if there was any changes to compression or did they simply run slightly a slightly different map?....hmm i would think map.

Wikipedia:
Four cylinder diesel models were equipped with the same OM601 engine of the 190, in the 2.0 L and 2.2 L versions. Many of these diesel variants were sold as taxis, due to their low fuel consumption and strong reliability. There were also more powerful five cylinder engines (OM602) which were available in naturally aspired (C 250 D) and turbocharged (C 250 TD) forms. The Turbodiesel was introduced in 1995 and is one of the novelties in the engine range available from this year. The most important was a supercharged version of the M111 straight four, the C 230 Kompressor, using a Roots-type supercharger to generate 193 PS (190 hp/142 kW) at 5300 rpm: Mercedes-Benz reused supercharger technology after 50 years. Due to Italian and Portuguese car tax rules, export models in Portugal and Italy featured a supercharged version of the smaller 2.0 L (C 200 Kompressor), which had a similar output of the C 230 Kompressor.


Paul

[Pagz]

hmmm then i found this:

The C230 Kompressor is powered by the same double overhead cam, 16-valve inline-4 that goes under the hood of the SLK roadster. The crankshaft-driven supercharger compresses intake air that is then cooled by an intercooler packing the engine with a dense charge. The 2.3-liter engine produces an impressive 185 horsepower at 5300 rpm. Maximum engine speed is only 5800 rpm, but the supercharger and 10.4:1 compression ratio yield a broad torque plateau, generating 200 foot-pounds of torque from 2500 rpm to 4800 rpm. That's more torque and at lower revs than the 2.8-liter V6 in the C280. The C280 is smoother and quieter, while the Kompressor rewards the driver with more mechanical sounds when pushed hard.


Source:

http://www.automallusa.net/1999/mercedes-benz/c-class/reviews.html

[Pagz]

and then this...which gives 8.8 and 193hp

http://www.autowp.ru/mercedes-benz/c-klasse_202/specifications/

[xvvvz]

>>that must be the US spec engine??<<

Correct. It is the same data that is written in the 1999 brochure.

>>from all my googling im pretty sure the Euro spec is 192hp,and uses minimum 92 octane?...<<

There is variation. The variation can be from year to year and model to model (e.g. SLK230) as I remember from reading/comparing specs over the years.

Don't forget that later "230" engines weren't really 2.3 liters. I wouldn't trust the specifications quoted by auto review sites for an important technical decision because I have seen them get the numbers wrong more than once.

[dshenberger]

My owners manual has the engine specs in it.

[Proven Guilty]

the euro spec was usually run on better gas. the best we get in the stats is 91 in california, and sometimes 93 octane in the midwest.

i'm pretty sure the 8.8:1 is the compression designed pre-boost. the 10.4:1 on the article from the SLK is probably what its deisgned for while everything is functioning and running.

i'm curious to know slammed_c's compression with his kleeman at 11lbs ;)

[Cru328prod]

msn shoots different numbers

2.3L 185 hp I4
Horsepower 185 @ 5500 RPM
Torque (lb-ft) 207 @ 1800 RPM
Valves/Valve Configuration 16/DOHC
Displacement (cc) 2290
Bore X Stroke (in.) 3.54 X 3.54
Compression Ratio 9.3:1
Fuel Type/System Gas/MPFI


i want 11 pounds of booost!!!!

hey paul did u ever get my message, i'm trying to figure out that PCV valve crap..i managed to use a coupler and put it back, but i want to replace the whole system. I'm getting a very strange rev now, its all the time now.....if i drive around and put it in park it will stay above 1k rpm like if i was tapping the gas, even when i'm driving it will "ghost ride the whip"

[SLAMMED_C]

Yo Paul!!.. I was always under the impression the compression ratio for the C230 Kompressor was 8.8:1.. and I just looked it up in my owners manual and verified it. it is indeed 8.8:1.

I run between 11-13lbs of boost (depending on how cold the air is!) Kleemann kicks ass!!

[Cru328prod]

whos stilllllll selling it?

[c280nz]

im running 7pounds at 10:1 comp :D
what are u up to paul? hows the project going? new pistons needed?

i cranked it up to 9pounds and the clutch didnt like that much when the torque came on at about 4000rpm :( so later this year i mite uprate the clamp on my clutch,
ive settled for 7 til then

[SLAMMED_C]

Originally posted by Cru328prod
whos stilllllll selling it?
kleemann does not sell it any more, ASP sells a kit still I believe. And dynospot I think makes a pulley. Not as much boost as the kleemann pulley, but still an improvement.

[Cru328prod]

yea i know its only 8pounds........

i don't get what proven was telling me before.....i thought a smaller pulley would make it do more rotations?

[Proven Guilty]

Originally posted by Cru328prod
yea i know its only 8pounds........

i don't get what proven was telling me before.....i thought a smaller pulley would make it do more rotations?

the asp pulley is a crank pulley with a larger diameter, but uses the stock pulley on the supercharger. if the supercharger pulley was smaller it would make it spin faster. it's the same effect

[Cru328prod]

ahhhhh im soo fu*kin dumb i get it now