under drive pulley queston

[Sonny]

Is it true that if change your UDP(smaller) for alittle more horse power it will effect the power needed for your sound system? If so can anything be done about it, because I would like have both HP with good sounds. I know the UDP is only a few extra HPs but I have other mods also and every little bit counts when you don't have much to start with(P5).

 

[got wake?]

UDP's allow more HP to the wheels 2 ways. 1 being that the crank pulley is lighter, and 2, which is what you are worried about, the alternator won't spin as fast because the crank pully is smaller. i haven't done any real research into UDP's, i'm just going from what makes sense in my head.

most alternators put out full current at around 2k rpms anyways, so if you put on the UDP, you'll reach full output around say 2.5k rpms. however that will also make it put out less at idle. that's when you run into problems when dealing with a system. i'd recomend going to a local alternator rebuild shop and tell them the specs of the UDP and have them put on a new pully for the alt, so that it reaches full output as soon, or even sooner than stock.

 

[Brian MP5T]

The Alternator Spins Slower, So it makes less power. Most noticable when stopped at a light...

 

[Sonny]

UDP's allow more HP to the wheels 2 ways. 1 being that the crank pulley is lighter, and 2, which is what you are worried about, the alternator won't spin as fast because the crank pully is smaller. i haven't done any real research into UDP's, i'm just going from what makes sense in my head.

most alternators put out full current at around 2k rpms anyways, so if you put on the UDP, you'll reach full output around say 2.5k rpms. however that will also make it put out less at idle. that's when you run into problems when dealing with a system. i'd recomend going to a local alternator rebuild shop and tell them the specs of the UDP and have them put on a new pully for the alt, so that it reaches full output as soon, or even sooner than stock.

THANKS, that makes a lot of since, I wish I would have thought of that. I'm going to check into it. thanks again.