OJwerks

Im working on retrofitting a C32 supercharger (thanks AMG Jerry) on to my SLK320..... One thing im stuck on is what would be the best method to lower the boost??? I believe the C32 blower peaks out at 14.5lbs stock ?? Is this true?? Anyways, I need to lower it to a solid 6lbs.... should I get a custom "larger" pulley done for the blower itself or should I get a smaller crank pulley ?? Any ideas / suggestions greatly appreciated.........

N.M.M.

I would assume it would cost less to have a custom crank pully made. probably easier too.

sales@eurocharged.com

I would go with the smaller crank pulley.

Another option would be to use a thicker head gasket / spacer to lower the compression ratio.

I lost about 3.5lbs of boost after I ported my heads, so that would be an option too. If you get the heads ported, then they could do some work on the combustion chamber and lower the compression ratio there too.

Good luck with the project!

Eurocharged Rick

the one thing to keep in mind when going with a smaller crank pulley is that if you do this, you will have to address the other accessories that will be slowing down...in other words, you don't want to go too small otherwise you will cause other problems...

i can probably have a custom crank pulley made for you, just let me know if you are interested and i can check into it...

spr

I have read about how more efficient exhuast also reduces some boost... why is that exactly? Would it have to do with the valve overlap and the fact that it is allowing more to get out before the exhaust valve fully closes? That would make the most sense.

m444

It is not really boost per se, that gives more power, it is the volume of Oxygen and Fuel combustion , one can push through the engine, per revolution. The boost is just a measure of how much extra air is being pumped into the engine. If the exhaust/intake flows easier, then there is less restriction/back pressure, which may lower the boost, but not the volume of air.

spr

that makes no sense if the exhaust valve is closed-

OJwerks

thats the reason why I wanted to steer-away from the crank pulley idea, but Ill deff. consider your offer... thanks!

OJwerks

thing is I dont want to mess with the anything on the engine until i get the blower itself running properly, once the blower is running properly ill look into raising boost and porting & all that..i can always go back to the stock crank pulley and run the 14lbs.... but I doubt that I will ever run more than that on "stock" internals........

OJwerks

1FASTC32 you got PM!!

m444

The exhaust valve is only closed for very short time, as is the intake valve. Typically, there is also some valve exhaust/intake overlap time, which helps with high RPM HP.

If the exhaust valves never opened, then the engine would not run.

OJwerks

as an update to this... i wanted to say that ASP is going to manufacture for me a one-off S/C pulley that will limit boost to a "Whopping"(lol) 7lbs of boost.

Once I get this... its off to finally mount everything on the car, btw... the clutch is going to be engaged at all times... were adding a bypass valve to the whole system...

TruTaing

Cool project. Ive been watching this whole time!

Keep us updated. Itd be really dang cool if ya got pix of the whole engine in pieces/what nots Ive always wondered what the intake manifold looks like off m112.

OJwerks

yeah, Ill get picks of everything and all the process once we actually get started with mounting everything on the car.....

as of now... Im only missing one part.. the "intercooler" ... the wrest is all there..

1. S/C & hardware
2. Intake plenums
3. I/C pump
4. Heat Exchanger
5. FMU
6. Colder Plugs
7. Pulley (in the works)

Once I finally get the new pulley, figure out what new belt to use and get the intercooler (ive been trying to get a used one and save some couple $$$, but if worse comes to worse ill just buy it new) Ill mount everything on the car..

For all of you that are wondering Cost on this... its all been kept well under $3K.. but I still need to add the cost of the Intercooler... and after that im budgeting another $500 for all miscellaneous stuff, dyno time..etc etc. Im trying to keep everything under $5000 to make it all worth it.

TruTaing

Awesome! Would ya be willing to take pix of all the parts before ya put them on? :x

Im surprised you dont have a more detailed thread in the r170 forums...

What kinda numbers are you expecting from this lil adventure?

OJwerks

the R170 forum here has amost zero activity... on benzworld its a diff. story....

to be honest, im hoping to match or surpass Kleeman numbers...

tylerxfire

hey guys, new to the site, hoping to pick some stuff up from you mb guys, i have a crossfire roadster, na, and i have intake, exhaust, ngk iridiums, all 12 of them, lol, and a zex 75 shot, i am looking to do a low boost setup, i see you are using a c32 blower i hope this works out for you can you give me an idea of where to get parts and what i should go with. i also think the custom pulley is the way to go.

sales@eurocharged.com

I have a spare Supercharger and spare intercooler for sale. Complete and ready to go!