[bmac]

Underdrive Pulleys?? Which one should I get?

 

[Jurgen]

i am about to get some U/D pulleys and most people told me if u have the money
go with the Stedda pulleys they r already balanced and they r better and the march perf
u have to reuse ur balancer or they have some on carpars.com i think they say r march perf
and they go for $58

 

[GreenBird]

Despite...

the ghetto english...he is right. the steeda pullies are the best. a secondary option is the ford FRPP set. you just get a set for a 96-98 GT. There are sets that are for 96-01 but you have to make sure that the water pump pulley is the same design, other wise your water pump pulley won't stick out far enough. If you do happen to ge the wrong set, you will be able to tell by comparing the water pump pullies...it is easy to see.

 

[WaLieN]

For the Steeda ones, get the ones that fit the "96-01" Mustang GT's. You can get a set off ebay for about $125 shipped.

 

[bmac]

Despite... the ghetto english

No kidding! Thanks for the info.
So just to be sure get the steeda U/P's for a 96-01 Mustang GT.

 

[GreenBird]

No kidding! Thanks for the info.
So just to be sure get the steeda U/P's for a 96-01 Mustang GT.

Double checked my info...the change is mid 2002, not mid 2001 like I thought.
Any 96-01 kit will work.

 

[UltraChicken]

I've heard from people who have worked on other cars (hondas, Camero, ect.) that underdriving the alternator is a bad idea. Does anyone have any exeriance good/bad?
Thanks,
Josh

 

[WaLieN]

Why would it be bad at all? If anything, it would be good, because you're making it work much less that it should.

 

[UltraChicken]

My assumption is that underdriving the alternator is bad because you are getting a lower charge from it. Am I right or is this idea just an old mechanics tale? And if so does anyone know of a low spin alternator?
Josh

 

[BR1]

mine works fine. 5K miles on them now, no charge issues whatsoever, and i have 2 batteries, 2000watts rms stereo. i can't understand that tale because the alternator is spinning fast when the car is at 5000 rpm, and when its at idle the alt is spinning slow. what is another 200 rpm drop causes by the pulleys??? nothing.

 

[GreenBird]

My assumption is that underdriving the alternator is bad because you are getting a lower charge from it. Am I right or is this idea just an old mechanics tale? And if so does anyone know of a low spin alternator?
Josh

Most kits will have full charge rpm listed. Most are around 1000rpms. The only way to get in trouble would to sit and idle you car for a long period of time with a big stereo booming.

 

[Robinson]

personally, ive yet to see an electrical system fail due to underdrive pullies. yes it will require a higher rpm to fully charge(small when you consider the operating range of the engine) but like everyone is saying, unless you just sit the car at idle, turn on all your accessories and have a power-hogging stereo, its not going to be a problem. a couple seconds back at the charge rpm and you are good to go anyway.

 

[Jurgen]

i havet got my pulleys yet but people say that theres not a big difference in size
so it shouldt be a big problem and i have seen em so i dont know y they sell the ALT
pulley

 

[Robinson]

i havet got my pulleys yet but people say that theres not a big difference in size
so it shouldt be a big problem and i have seen em so i dont know y they sell the ALT
pulley

its funny you mention that, because when i compared my March alternator pully to the stock one, there was NO difference. too tired to know for sure, but i think that if you spin the crank quicker, it will have to spin the alternator slower, hence the lower speed, but im not positive on that and i dont feel like checking

 

[GreenBird]

its funny you mention that, because when i compared my March alternator pully to the stock one, there was NO difference. too tired to know for sure, but i think that if you spin the crank quicker, it will have to spin the alternator slower, hence the lower speed, but im not positive on that and i dont feel like checking

a smaller crank pulley leads to slower belt speed, which will make everything spin slower. to keep something spinning the same speed per RPM as before you must replace it with an equal ratio pulley as the crank. So if the new crank pulley is 20% smaller, to keep the alt spped the same the new alt pulley needs to be 20% smaller.