Marky

Maybe a stupid question but what is an underdrive pulley and what does it do? I have read about these pulleys but my english isnt that good so I havent figured out what a pulley is. I have got an E55. Would an underdrive pulley be god for that car?

Marky

Mach430

We make underdrive pulleys for the Mercedes.

The power steering pump, water pump, and alternator all require pulleys in order to make them work. The pulleys run off the engine crank which spins them via a belt. As the individual pulleys are spun, they power up their appropriate accessories. Automobile manufacturers always provide more power to these components, which is fine, except that spinning them requires power from the enging that could be used at the wheels instead. We underdrive the components, still leaving them at a reliable level, by using larger pulleys. These pulleys are also made lighter, resulting in the engine working less to spin the accessories. The air conditioning is not affected. The only negative aspect to the underdrive pulleys is that your alternator spins slower, and will not have enough power to supply a large aftermarket stereo system. The crank pulley is not changed, so there is no reason to worry about it effecting the crank. The pulleys are an easy, low-cost, reliable way to get another 15HP at the wheels--from a standing start!

Feel free to email me if you have any questions. I'd be happy to explain further.

Thanks

Ben

Marky

Thank you very much!

Marky

W0n6_3d4n

any pulley for the 2 litre engine on c class

Mach430

Sorry, at this time we only have underdrive pulleys for the V6 and V8 motors from 1998 and on.

dronell19

So none for the C200K either, then?

oCKompressor420

i got this question answered before, but i wanna tune up the kompressor in my c230. should i get aftermarket crankshaft pulley so i can get more beef outta mt supercharger?

thanks

Mach430

Yes, the boost upgrade which you are looking for is completely different than the underdrive pulleys which we offer. I would recommend the Kleemann pulley upgrade for your car, which will include the Mass Airflow Relocation parts necessary to remove the flat spot the car has in it's power curve at 3,000 rpms (pre-6/00 cars). Gains of about 20% can be expected with this kit.

shtatc

Ben(mach430),
How did you decide on the "optimum" size/diametre of the underdrive pullies? Is there a max or min size diametre where any more or less size will not "underdrive" the accessories? Is there an optimum amount of "underdrive" that you were looking for when you decided on the current pullies? Hope these questions make sense.
Thanks,

Scott

Mach430

I can't release exactly how we choose what sizes to make our pulleys at, but I can answer some of your questions. Yes, there is definitely a point for any accessory where it would be underdriven too far. We design our pulleys to be reliable; producing power without drawbacks. Underdriving any component to it's max would result in it not functioning, as it would have no power to run. The way our pulleys are designed, the accessories still have enough power to run reliably and smoothly. The only drawback we have ever experienced is that if you have a large aftermarket stereo in your car, you do not want to underdrive your alternator. Doing so could cause power drain on your battery, and your alternator to strain. If you have a large stereo, simply don't use the alternator pulley.

Besides that, it's an easy 13HP at the wheels. Ask BrabusCClass. He has had our pulleys for a few months on his C240, and is very happy with them.

Thanks

Ben

dronell19

Ben - how much gain should I expect from these pulleys on an E46 323? Do you have a dyno sheet?

Mach430

About 5-6HP at the wheels. Eurotuner magazine has a dyno of a 323 with out pulleys.