Here's a dyno done with the Lightened Crank Pulley on a C55. This is the same pulley for the v6 that we offer.

http://www.mbworld.org/forums/showthread.php?t=248211

Gains should be about 60-70% of what the v8 shows. That's about 9-12RWHP through the power band and about 6 ft/lbs TQ. Plus better gas mileage, improved throttle response, smoother shifts, and an overall increased sense of happiness (may or may not occur in every customer).

We will offer the Crank Pulley and Underdrive Kit as a package deal for 775.00 shipped, which is a 24.99 savings.

PM me if interested in the package.

 

when adding the underdrive pulleys and things, do other things need to be upgraded like water pump for example, my buddy said something about having water pump issues because of his underdrive pullies on his m3. so 9 - 12 rwhp for just the lightened crank pulley, and how much for the underdrive pullies. and are you positive that i could get a belt at auto zone or something, how about a part number to check?

 

what material is your pulley made from? where do I buy it? how many pounds or ounces is the weight difference?

 

Stock Crank Pulley: 6.8 lbs
Lightened Crank Pulley: 2.2 lbs

Made from Billet Aluminum

Can purchase here: http://www.tvtdesign.com/inc/sdetail/616

Belt Part #: K060955


The water pump is not adversely affected by these mods. M3 is a different besat entirely.

 

the water pump pulleys are the same size.. the new one is much lighter however..

 

so, should i expect better responce out of this than the 55 did? my thinking is that motor is likely turning the same accessories as i am but with a more powerful motor so i should see a better gain right?

 

You will se a less total gain and an equal percentage gain.

 

well, that sucks. i want one with more total gain and more %gain.

i have to really think about this, because if you have motor x with 350ft/lbs and motor y with 250ft/lbs and you take the same load/weight off each motor, i would think the weaker motor would respond better due to how much harder its working. also looking at the fact that motor y has a shorter crank so the same amount of weight removed will actually be a higher percentage of weight loss on its rotating assembly than motor x.

where am i getting confused here?

 

i think maybe a light bulb just turned on in my head. i'm forgetting one key item in my above post. even though the overall percentage of rotating weight is reduced more on the v6, the v8 holds 2 more power pulses which inturn give it the destinct advantage and makes it in aplication respond with greater power increase, simply because its makeing more to begine with. i know i didn't word this exactly how i'm putting it together in my head, but i think i'm getting on track with it now. i really would like to see a dyno in a n/a 3.2.

 

Ok, bear with me, not a mechanical engineer by any means!

It would seem to me that the heavier crank pulley would actually help once it is in motion due to increased weight/mass keeping its inertia? I can see a faster start but also a faster slow down, I.E. it would take more power to keep the lighter pulley spinning at 4500 RPM once you hit 4500 RPM?

 

i think that would mostly help with torque at you're shift points, but lighter is better everywhere else.