how much hp?
power increases with a lightened pulley are exponential to what mods you already have on your car. so if you have nothing, you will prolly see nothing(maybe a little). if you were at 400hp though, you could prolly see a 20hp gain.
im pretty sure the underdrive pulley is a replacement for the pulley that drives the cam gears via the timing belt, and it is just much lighter than oem.
im pretty sure the underdrive pulley is a replacement for the pulley that drives the cam gears via the timing belt, and it is just much lighter than oem.
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Joined: Mar 2002
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From: Los Lunas, New Mexico, USA.
Vehicle: 2001 Hyundai Tiburon, 2004 Kia Sorento, 2010 Kia Soul
The lighter something is the less force it takes to turn it, hence, you get HP back.
Like Tibby01 said though, it's not always much, but can add up.
Like Tibby01 said though, it's not always much, but can add up.
well.. I remember weighing the stock crank pulley.. it was something around 6 pounds.. the UR puelley I installed weighed less than 1. I cannot tell you about any gains, I also installed the 1.8 intake cam at the same time.. there was an increase, but which was giving it, I cannot tell you.
I thought I read somewhere that the underdrive pully would throw off the crank balance or something and start screwing things up. Did anyone actually confirm that or did it end up being BS as far as we know?
I may have to look into getting one then. I was kind of holding out until I heard from someone that has had it for awhile so I don't have to really worry about fixing something that broke while I was trying to make it better.


