Underdrive Pully & MPG

upstop

Member
Has anyone that has swaped out thier underdrive pully paid atention to thier gas millege?

In theroy since it takes less energy to spin with a lighter pully. One would assume that would make gas milege drop. This would be a plus.

What is the diameter diffrence in the aftermarket pullys?

Was it easy to install? Did you have adaquit clearnce, or should I just pull the motor.

I am thinking about puting one in, but I will only do it if its worth the $$$, and I am looking under the hood thinking maby I should just take it to a shop cause it looks like its a b**** unless you pull the motor....
 
on my previous car i did notice a slight increase in mpg, but nothing huge.

diameter difference - most companies dont release this info

ease of install - yep, pretty easy - just remove the plastic cover.


fyi - rr-racing will be bringing out a underdrive pulley soon. should be around $140usd
 
It depends on how you drive i guess. Although the engine has less weight on it u will be reving it more/quicker and thereby using more gas. With all my mods i have pretty much maintained my factory gas mileage.
 
My question about the diamater refers to the stock pulley Vs. aftermarket. If the aftermarket pulley is larger or smaller in diamater it will change the RPM of the alternator, power stearing pump, AC compressor.

I am not saying that is a bad thing but I dont want shorten the life of any components or make my AC less efficent/effective.

Rember most aftermarket parts are designed for power/preformance not the longevity of the rest of the equiptment thay come in contact with....

I used to make exhusts for dirt bikes. it was all about power not what was best for the life of the motor.....
 
the diamater is smaller. U will have less power to your accessories. Normally everything will work fine unless u have alot of draw on the alternator, stereo system, and u might have slippage. However i have never had a battery die or an accessory fail or not work and i have had it for 30k miles at least. hope that helps.
 
thanks I wouldent think it would affect anything but ya never know.

so you do have to get new belts then.... Thay should be included but then I suspect that its actualy the same Pulley in the same package for many diffrent aplications...

Cheep bastards
 
Back