Hello guys.
I would like to know the fuel efficiency after installing UR underdrive pulley.
I heard that underdrive pulley brings higher rev of the engine.
So I was wondering if it drops the MPG.

Lastly, what about the stock size UR pulley?

Thanks~

 

It doesn't bring the RPM's any higher. The stock redline is still in place. The pulley does not effect the ECU or electronics. It improves throttle response. Also the pulley will save you gas mileage. Check out UR's homepage.

http://www.unorthodoxracing.com/

 

I see. Thank you for the reply.
I have one more question. Where can I purchase stock size UR pulley?
and how much is stock size?
I know visionary racing has underdrive UR pulley but...
That's all I know.

 

Here's what Unorthodox says about pulleys and pulley kits (only the crank pulley is available for the RL):

Our pulley sets provide most of the power gains through weight loss (80-85%). The remaining part of the gains from these pulleys comes from underdriving of all the accessories (15-20%).However, we do not push underdriving for two main reasons. First, it is important to keep charging systems, air conditioning, power steering, and water pumps moving fast enough for every day driving. Second, not much horsepower is gained from extreme underdriving.
In most applications all of our underdriving is done with the crank pulley, not the accessory pulleys. This is done so maximum weight loss can be achieved at the crank where most of the horsepower gains are found.

With our stock diameter pulley sets the alternator and other accessories spin at stock speeds with NO underdrive. This is also important for stock or aftermarket supercharger systems. These systems are either driven off the alternator, air conditioning or power steering sections of the crank pulley and now you can use our stock diameter pulley sets with these supercharger systems and have the same boost you had with the factory crank pulley.st level with the use of the factory diameter crank pulley.
100% of the power gains from the stock pulley sets comes only from weight reduction versus the factory crank pulley. The reduced weight allows for more power transfer to the drive wheels. The stock diameter crank pulleys are available in polished finish only.


Excellerate and Visionary Racing sell them.

 

We have these in stock.

http://store.excelerateperformance.com

020611402 for the underdrive
020611412 for the stock size

 

My car has the pulley the intake and the exhaust and i get 30+mpg highway. Im very happy with it.

 

Donsnyder 30+ mpg? I'm very surprised. I think those 3 mods makes your car go poewrful enough without much of gas. I'd better buy them. Thanks. ^^