i dont know man, my friend had an underdrive pulley installed on his car and he said he felt a difference.... :dunno:

not sayin you guys are wrong but some guys swear by pulleys and some swear them off...

 

need dyno results, they swear by pulleys but it could all be mental.

 

pulley upgrades for the most part are a marketing gimmick to make more money. for most people out on the streets with 15sec cars and slower, it doesnt do shit.

 

Excatly, only pulley thats worth a damn is a supercharger upgrade pulley. trust me if some on says aem pulleys helped, its all mental

 

Two friends each with 2000 base model Preludes. Both had AEM CAI, stock header, exhaust, and a VAFC. One had AEM pullies and the other didn't, that was the only difference in the cars. They dynoed back to back. Car 1 (no pullies) made 174.6whp and 140wtq. Car 2 (with pullies) made 174.8whp and 141wtq.

The peak numbers are more or less identical. The difference could have been due to the straps on the dyno, tire pressure, etc. I wish I still had the dyno plots ... the curves were identical. In other words, pullies don't do anything. Others may have a different opinion, but I've seen the evidence first hand.

 

Pulleys will free up horsepower by increasing the leverage(smaller pulley) on the crank pulley.... and or larger pulleys on the accessories will do the same.

(another GREAT advantage is that a good crank pulley will be lighter than stock also)

warning----ANYTIME you use pulleys to increase horsepower you are lowering the speed at which your accessories pulleys spin, this could affect your enjoyment of daily driving...... for example, your alternator may have trouble keeping up under loads, stereo, highbeams ect.. you could also run into problems with your A/C not performing as well as stock.... stuff like that

 

id rather take out my spare tire for free to be "quicker"

 

Great, thanks for posting the theory used to sell pulleys right after someone posted fact to the contrary.
That's right folks, pullies don't do jack.

 

Excuse me, the "theory" i explained is based PURELY on math and physics.
FACT: for every pound of rotating weight lost on the crankshaft, you will gain roughly 2.7 hp.
FACT: Leverage exists, to deny this shows a lack of knowledge of physics. A larger crank pulley requires less effort for the engine to turn the accessories.(ever heard of drag racers taking off their belts for a race.... its because the accessories take a large amount of power to turn, the pulleys use the same idea except they allow you to stay a daily driver)(also... think about turning a rusty bolt, would you rather have a 3 inch wrench or a breaker bar?)

I did not claim that whoever(acura owners included) puts on pulleys will be satisfied, as far as i know the VTECS pulley may be as light as it can get or there may be some other factor which limits how much under drive the VTEC's accessories can handle.
I stated the FACTs that the guy needed, and also the warning that he needed about possible side affects of underdriving the accesories.

Shivers may be completely right(i cant prove that he isnt...and I actually could care less if hes right or wrong), What i am saying is that as far as FACTS go, my facts can be proven with any old hand calculator..... his depend on the honor system and his own memory.

Perhaps you should look at a dictionary to find out what the difference is between FACT and THEORY

PS: Nothing against shivers/ but the premise of the "FACT" statement is that both preludes were Exactly the same except for the pulley, there are no cars exactly the same. They could have pulled of the assembly line with anywhere from 0-8 difference in horsepower, hell one of them could have a engine problem that is unnoticed..... for his FACT to be an actual FACT we need to see actual dyno results on, before and after the pulley swap.

 

It is widely known practical knowledge that pullies don't do much of anything. You can quote physics as much as you please, but pullies still don't really help.