Underdrive Pulley's???

[wannaberacer]

if i put one will my car gain some hp???does it really work, kung sakali san sya mabibili dito

[Edwin]

pulleys or lightened underdrive pulleys will really not give you considerable hp gain, though your engine will work better because of the weight reduction and drivetime of the pulleys.

HTH.

[3M TA3]

you might experience overheating. in milder climates, UDP's are ok. it might be a different story in the tropics. the underdrive might slow down the water pump too much causing your engine to overheat.

[R-A-Y]

I cannot remember accurately the issu with the nderdrive pulleys, but I think it was that when you install these lighter and larger aftermarket pulleys you may have to relocate or completely remove the power steering system in your car. Someone correct me if I'm wrong

3M TA3
How do the pulleys slow down the water pump? Is it because it takes more effort in turning it since it is larger than the stock pulleys?

[3M TA3]

when you install underdrive pulleys, youre basically slowing down the rpm of your accesories- alternator, ps pump, water pump and ac compressor- thus reducing the load on you engine and freeing up horsepower consumed by your accesory drives. this is achieved by putting larger pulleys on the accesory drives and smaller pulley on the crankshaft. the size of the pulley determines the rpm of a given accesory drive- larger pulley is slower and smaller pulley is faster. with the crankshaft pulley, the one that powers all accesory dirve pulleys, its the opposite.

[Wolvie]

There are 2 ways to free up power using underdrive pulleys.  the main engine pulley can either be reduced in size or in weight.  I used Unorthodox Racings pulleys because they concentrate more on the reduction of weight so that parasitic loss due to inertial drag is minimized.  It is not desirable to make drastic changes to size because it has direct effect on the functionality of your auxillary components (i.e alternator, water pump, etc.)

[HondaCarb]

if i put one will my car gain some hp???does it really work, kung sakali san sya mabibili dito


Pulley changes are OK especially kung lightened pulley sila.  I suggest not to modify the size.

To top it all, if you buy one, I highly recommend to buy FIRST the 'CRANK PULLEY' because you want power.  This is my answer cujoh!  Be sure when you install one, decide kung you still want it with the belt for alternator and steering wheel.  If not, buy a crank pulley without partition for the above.  Am sure sasaya ka na niyan.  Pa-install mo lang sa marunong sa brand ng car mo.  Later, you can buy na the lightened pulleys you are talkin about (like the AEM pulleys).  Enjoy bata!