cobalt pulleys

[zmatt]

I just occured to me. Cobalt SSs use M62s without a clutch and those guys routinely run twice the boost we do. Has anyone considered doing a clutch delete and running an agressive cobalt pulley for 12+ psi? Im going to email eaton tomorrow and see if the pulleys are standardized (they should be) and if i can easily use one. If so then we have acess to pulleys good for up to 15psi.

[Mike51809]

That would be sweet! When you take the clutch off will it effect the warm up?

[zmatt]

The blower would always be on, it would likely throw a check engine light unless you were able to modify the ecu to ignore that or you have a standalone.

[Mike51809]

It'd be worth it to get some power! The m111 screams at high rpm n with some more boost it'd be an eargasm

[zmatt]

I just emailed the product technical support rep at Magnuson (they handle all of Eaton's aftermarket support in the US). I left a fairly detailed email and hopefully he will get back to me with good news.

[zmatt]

ok so cobalt pulleys will not work, they use a hex nut and outs are press fit, however if our pulleys have the same offset and internal diameter as the Nissan Xtera and Frontier pulleys then we can use those. The shaft measurement is .78" or ~3/4" that offset is .33" or 8.4mm. Does anyone have a pulley laying around that they can measure? The internal diameter is straight forward. here is a guide to measuring the offset

http://www.pulleyboys.com/store/pages.php?pageid=3

[SLAMMED_C]

hmm.. good idea with the cobalt charger pulley. however I was going to say that the supercharger nose is different from the cobalt and the benz (due to non clutch and clutch version). that is your only thing to overcome with having a custom pulley for the benz charger. there is no way to put a custom pulley on the benz charger. its just the way the clutch is on the charger, and it is not press fit on either, but once you remove the clutch.. there is no way to put a different pulley on it. you need to get that cobalt charger nose for the benz charger.
if the cobalt charger and the mercedes charger are the same.. id just get the nose of the supercharger off of a cobalt and bolt it to the benz one (if they are at all the same in regards to size and where everything bolts together). then you can run a cobalt pulley.
but that is another thing there too.. you will need to figure out the size of a pulley to run based on the crank pulley size. if you run too small of a pulley on the charger, you will grenade it! overspin it and overboost.
look into getting a cobalt charger nose, then you will be closer to doing a pretty good mod for increasing boost.

[zmatt]

The snouts are interchangeable but due to where the cobalt's supercharger is located it is longer than the benz one and wouldn't line up with the belt. Also a general rule of thumb is every 1/10" smaller is about 1psi extra. Also it is a press fit type, Eaton confirmed it was, the pulley just has an integrated clutch. There is a tool to remove and install the pulleys.

http://www.pulleyboys.com/M62.pdf

I'm working on finding out the pulley offset and inside diameter to see if they match up with Nissan pulleys. If they do then we are in business. If not then at least we have the specs to make our own.

[SLAMMED_C]

The snouts are interchangeable but due to where the cobalt's supercharger is located it is longer than the benz one and wouldn't line up with the belt. Also a general rule of thumb is every 1/10" smaller is about 1psi extra. Also it is a press fit type, Eaton confirmed it was, the pulley just has an integrated clutch. There is a tool to remove and install the pulleys.

http://www.pulleyboys.com/M62.pdf

I'm working on finding out the pulley offset and inside diameter to see if they match up with Nissan pulleys. If they do then we are in business. If not then at least we have the specs to make our own.

I thought you were talking about the 1999-2000 generation M111 eaton supercharger on the w202.. but now I realized there is another version of the M111 eaton charger with a solid pulley on it and no clutch (later generation r170 SLK and the early generation w203 c coupe), that one is press fit. well why not just go with the nose of that charger? same or is it different? Im pretty sure the charger body is slightly different, im not sure about the nose section however.

[zmatt]

They told me the clutch is press fit as well. anyways I don't know. I'm trying to figure out the pulley dimensions to see where to go to next. data is scarce though.

[SLAMMED_C]

They told me the clutch is press fit as well. anyways I don't know. I'm trying to figure out the pulley dimensions to see where to go to next. data is scarce though.

I can tell you for sure the clutch on the Kompressr is not press fit. there is a small 8mm or 10mm bolt in the center of the clutch.. and then there is a circlip that holds the clutch onto the snout. and then i believe 3 or 4 small hex head bolts holding the electromagnet to the snout as well.

[zmatt]

well thats confusing.

[zmatt]

ok Thanks to some work user Subby over at benzworld has done I have learned this about the 230k. You can fit a smaller blower pulley, but you wont be buying one. You have to find a machine shop to machine the stock 94mm one down to 87mm. If you combine that with the ASP pulley you will be making about 1bar boost. This will also retain the magnetic clutch and you will not need a different belt or a new tensioner.



stock charger RPM:

(185mm crank pulley / 94mm sc pulley) x 5800rpm redline (auto)
= 11,414 RPM

ASP pulley RPM
(218mm crank pulley / 94mm sc pulley) x 5800rpm redline (auto)
= 13,451 RPM

doing s/c pulley ONLY RPM
(185mm crank pulley / 87mm sc pulley) x 5800rpm redline (auto)
= 12,333 RPM

ASP pulley RPM + smaller s/c pulley
(218mm crank pulley / 87mm sc pulley) x 5800rpm redline (auto)
= 14,533 RPM


In order to do this safely with the blower you will want to port it to improve airflow.

http://www.benzworld.org/forums/r170-slk-class/1516156-home-port-job-eaton-m62-s.html


Subby goes into detail on this in the above thread. I recommend finding a shop that knows blowers do this for you. With this done and an intake, catback and tune he says it spins all the way through first gear and he can pull stock Evos.

[koko202]

Man I wish i still had my c230k. I know a shop in socal that maufacters parts for superchargers.

[koko202]

they're called dream machine in van nuys. 818-778-6106

[Greeno]

hey guys, new to the club. i am looking to find out about putting an undersized pulley on my 99 c230. any suggestions? i am not sure what is the best for the $$ any suggestions would be great, thanks

[Mike51809]

I am seriously looking into having the stock supercharger pulley made smaller and porting the supercharger but i dont know where youd get a rebuild kit? And when you do port it does the shape matter like the guy did on benzworld?

[zmatt]

They guy on benzworld knew what he was doing. If I were you I would find a shop that knows superchargers and tell them to do it for you. You should be able to buy the rebuild kit from eaton, but if you dont know what you are doing then get someone who does. As for the size, there is a right and wrong size and shape. He did it that way to have the edges of the outlet to match with the tips of the rotors at 180 degrees ensuring a perfect seal and maximum efficiency.