just got my underdog, underrive pulley and new belt on. it was a pain in the *** to get off with out taking the fan shroud and fan off but we got it when i took off the old one and compared them, it seems way smaller than 20% haha.

 

nice work. how do you like it? notice much of a performance gain?

 

thanks it should give me 1-2 more mpg and i just drove it and at the same rpms andi usually acelerate, it is way quicker. then i punched it and had some spin in the tires, which i ouldnt even do when i had my lil stock tires

 

newb.

 

Is it really that good?

How much did that one pulley cost?

 

Do they offer this for the 4.0 too?

 

Yeah.

Here are the 4.0 specific ones they have.
4.0L Pulleys : Underdog-Performance, The Art of Power

 

haha

but it does make a hell of a diff , more than i thought

 

is worth getting the full kit?? i dont have a stereo system and i dont live in super hot weather so water pump and alternator pulleys rlly dont matter that much.. might just get the underdrive pulley only

 

just the crank pulley is all you need

 

no one calls mr cool aid a newb! you sleep with one eye open cus i be busting threw all your walls and kknock you house down...then i will take all liquids and make you die of dehidration

 

this pulley is $80, pays it self off in no time with the mpg increase

 

you're gonna be busting through a helluva lot of walls! lol. gonna cut me open and drain me of my red cool aid?

 

im mr. cool aid man, im used to those things, its my job...other than being red and tasty. and no way, you get grape drink cus you aint good enuff for my inerds

 

 

^ he did it, oh yeaaah.

 

I'm thinking about getting this thing for the 4.0. A good investment in the future if I can get better MPGs. Hell even 1 MPG better would be good for me, lol.

 

Just so you know...I ordered a crank & alternator pulley for my 4.0 from Wayne @ Underdog-Performance on October 7th, and it's still on backorder. Last I talked with Wayne, he said the manufacturer (ASP Racing) said they should start shipping them about the 1st of the year...but I don't know how many are backordered.

 

Wow, thats one long back order.

 

^Alright thanks for the heads up. It will be a while till I get enough money to buy it anyways, dang Christmas lol.

 

the 4l underdrive pulley is like 200 or something, i forget why but there is some special piece on it because of it being a 4L

 

Yep, on the 4.0's the crank pulley basically has a "built-in" harmonic balancer.

 

^ yeah what he said. Just gotta make sure you get the right tool to take off the stock pulley and you are good to go. I am pretty sure you can rent one at like advance auto parts or autozone.

 

You change just crank is it hard to find the right belt? That alone changes length right? Just wondering. I'd like to start working on some gas mileage stuff this year.

 

His website has a "belt guide" indicating the shorter lengths you need depending on the pully combinations you install.

GatorBack belt Size Guide [reference only] - $0.00 : Underdog-Performance, The Art of Power