daves4izzle::ASP 3-

I weighed the stock crank pulley tonight and here is the comparison:

ASP LW Billet Aluminum Crank Pulley: 1.5lbs (24oz)
Stock S4 Crank Pulley: 4 5/8lbs (74oz)

Weight difference: 3.125lbs (50oz)

Here are some pictures:

<img src="http://pictureposter.audiworld.com/110556/stage_3_parts_008.jpg">

<img src="http://pictureposter.audiworld.com/110556/asp_vs_stock_crank_pulley.jpg">

Z-Tuned (Alex)

Next question to be answered...was there a noticeable difference?

3.125lbs is a lot of weight off a pulley.

daves4izzle::ASP 3-

My car is still apart for stage 3 upgrades so I haven't driven the car yet with the new pulley on it.

Additionally, since I am doing so many other major upgrades, I will never know if the ASP pulley makes a difference.

daves4izzle::ASP 3-

Based on inertia calculations, with every 1 pound taken off of a crank pulley, approximately 2.7hp is gained at the crank due to less force required to spin the rotating assembly (which the pulley is part of).

Additionally, because our motors are FI (forced induction), there may be an even greater gain especially when under boost. Slightly faster turbo spool-up time and quicker progress through the rev range are also benefits of lightening the crank pulley.

So, because the ASP pulley gives us a weight savings of ~3.125 pounds over stock,

3.125 x 2.7 = 8.4375 theoretical horsepower gained at the crank

Now, like I said, this number may ultimately be higher because our motors are turbocharged. Also, the other effects of a lightweight pulley, as mentioned above, are probably just as beneficial as the raw hp gain.

JW944

this mod for over a year - do you know if it is balanced? I had someone bring this up in a conversation a while back and I never did find out.

Chaddy

Thanks; any idea on price?

homer-j-fong

its on their website

SRT8 eats 335i

Nahhhhhhhhhh, it must have just been an innocent little mistake, right?<ul><li><a href="http://www.autospeedperformance.com/Pulley/Pulleys.htm">http://www.autospeedperformance.com/Pulley/Pulleys.htm</a</li></ul>

Chaddy

Considering it - us A6 2.7T need all the help we can get to keep up with the B5 chassis.

homer-j-fong

Its actually under the B5 Passat but not the B5 Audi.

Guess they still have a bit of work to do on the new site. Looks great, but functionality is still a bit under performing.<ul><li><a href="http://www.autospeed.us/store.php?crn=240&amp;rn=413&amp;action=show_detai l">click</a></li></ul>