I know I probably sound retarded asking this, but exactly how do U/D pullies give you more power? How do they work, and how are they different from your stock pullies? I was just kinda wondering this the other day, and I finally got around to asking it.

Oh, BTW...ordered an SCT bout a week ago. Can't wait for it to come in :banana:

 

I believe that it makes the belt driven accessories like alternator and A/C compressor move slower and rob less horsepower, letting more HP get to the wheels. but i'm not an expert and only chimed in to add another question to this thread, is an underdrive pulley no good if you have a high powered soundsystem? I've heard it can hurt the alternator or electrical system if you are asking for more power than normal and have an U/D pulley.

 

Good Q....I was just wondering the same after reading your post.

 

UDP's are stupid, and are of no use for anyone. 10 hp max, and only at higher rpms, you'll never feel a hint of it during daily driving. And if you have a/c on and stereo pumping while its nighttime, your headlights will dim. I will never get udp's....ever

 

danny ever had them before?
I have the mach1000 and steeda underdrive pulleys my headlights dont dim and the car runs fine and pulls harder. They free power by making the everything on the belt turn slightly slower. Will it mess up your electrical system? no not at all. My alt shows 13.8volts being put out at idle stock is 14v i dont think thats to bad at all. And my a/c works just fine too, its takes it a tad longer to cool down thats about it.

 

You could just buy a u/d pully and an o/d pulley for the alternator...wouldnt that balance everything out?

 

ok who cares about exact voltage and if one person's car never felt the effects. For $200, I can tell you plenty of things that are more worth the money.

 

Just based on performance and gaining 8-10rwhp..... what other mod can get you that for $200? TB/Plenum....no...tuner...no....so for the money it's not a bad deal at all. I put Steeda UDP's on my 03 GT and I could notice a power gain at lower rpms....however, I did notice the A/C didn't blow as hard, but I didn't have any other problems with them.

 

actually UDP's are one of the best bankf or your buck mods. And it doesnt just pick up power up top, it picks it up all arround because your getting more hp from the crank to the wheels, no matter what RPM, also some UDP pulleys are lighter then stock, thus getting even more power.

And no, there are no problems with dimming lights or your A/C going bad.

and to top it off it increases your gas mileage.

On my stock 1994 3.8l mustang i put on an EBAY CAI and ebay UDP set and i picked up 2-4MPG on the HW

 

I only paid 100bucks for my pulleys, thats a good power to money ratio to me.
Most of the negative things you hear are form 5.0 guys. They had problems with them on 5.0's a few years back but that all seems to have been figured out now. Its your car though, if you dont wanna worry about possible problems dont get them. There are other mods but i personly see nothing wrong with them.

 

OK, so I have CAI, exhaust, and will have a tuner tuesday. What should I get next performance-wise if not UD Pulleys?

 

ok, get the pulleys. There's also a thing called the placebo effect...ever heard of it?

 

Have you ever had UDP's??? If you personally had them on your car and they caused issues or didn't give you any power gain then tell us about it.

 

Ha Ha dannys a Pulley hater!

 

yes I had them for about a week. Many people will put a cai or pulleys or hell even an INTAKE SPACER and claim to "feel" the added 2 hp. The fact is, people want to know that their $200 didnt go to waste. I'd sure as hell wanna feel somethin after throwin $200 down.


And you show me ANY dyno test that proves 10 rwhp that pulleys give. Show me just one.

 

Ok, 10rwhp might have been exaggerating a bit, but I would say 5-8rwhp....dude, all we are saying is that for $200 you can't beat 5-8rwhp....HP isn't cheap, you know that....Also, every little bit helps....so give me a list of other "GO" mods that will give you that for $200 or less?

By the way, why did you take the UDP's off your car? Were they causing issues? Also, I'll try to find some dyno results for you..

I should just give up cause you've already made up your mind and are a pulley hater! ha ha ha ha ha ha.....just like I'm a flowmaster hater! ha ha ha

 

it was kinda frustrating when we dynoed my brothers car after getting it supercharged... he was happy with the amount of power it was putting down, but hes never really driven a car around with more power than his (hes driven my cousins modded evo, but not for very long) and when we got the numbers back from chris over at XXtuning... we had several phone conversations with kenne bell. The car dynoed earlier on a dynojet at 238rwhp...(CAI, full exhaust, gears) it now maxed at 277 on a mustang dyno... hmm, funny, given KB advertises 350rwhp with his kit. Turns out his tune from KB was AWEFUL... they dyno tuned it at XX and its now making 360+ on a mustang dyno X_X
His line was 'I didnt pay ****ing 4000 dollars for 40hp!?'
yeah... i dont know why i typed that... the right tune means everything?

 

for the v6's they are a good mod, Justing from VMP has dyno tested them and they ARE worth it.

Im not going to throw out random numbers because i dont remember exactly what it made. If you want you can search for the post on v6power

 

You made a good point..HP isnt cheap. So spending $200 on something to get you possibly 10 hp at the crank is just a waste. I got my CAI right when i got my car so i didnt know any better. Otherwise, all performance on my car costed a little more, but was worth it.

And with the pulleys, things seemed a little off(a/c, lights, radio, etc) and the 10hpMAX wasnt worth the trouble