search....

 

I have....I've found group buys for NB and a bunch of garbage that isn't helpful and I've googled it and found a description of the basic idea of the mod. I need to know if it is better to go with a fullsize lightweight pulley or a smaller lightweight pulley. My main concern is with question #2 in the original post.

 

Nextgen or nick boer's are the guys to go to.

1. for a UD pulley you gain 9 whp in first, 4.5 in 2nd and so on. For a lightweight, 4.5 in first and 2.25 in 2nd and so on. Autos really are the ones that get the best gains out of this because where in 1st and 2nd longer.

2. Altenator can have problems, but alot of people havent seen any yet. If you have a big stereo system then dont get the UD.

3. doubt it

 

I've heard some talk about UD pulleys from some people and it sounds like a common mod for n/a cars. I'm wondering if this is something worth doing on a 03 v6. I just have a couple questions before I decide to take this route or not.

Question #1- Where do I gain the power (low, mid, high) and where could I lose some?

Question #2- Does this have any negative impact on any of the other components on the serpentine belt such as the alternator or a/c?

Question #3- Any impact on fuel economy?

Any brand recommendations are welcomed. But if Nextgen still has the sale, I'll probably go with them.

Question #1: How would you lose power? Read up why people buy pulleys, whether underdrive or fullsize lightweight, then consider whether you have interest in the mod or further questions. In either case you won't gain power. For a fullsize lightweight you just won't waste as much to initially get the pulley spinning since it'll now have less mass than the stock pulley. For the underdrive, you get even slightly better results than the fullsize lightweight because you reduce mass even more, plus you get additional benefits in that not as much energy is wasted in spinning the accessories. The amount of energy you save is most noticeable in the lower RPM's, especially in the lower gears.

Question #2: Underdrives, as mentioned above, won't spin the accessories as quickly due to the pulley's smaller diameter. That is the main selling point for why people purchase underdrive pulleys. Again, read up on a mod you are considering. Pretty much all the info is already available on here or on the internet.

Question #3: For all intents and purposes, no. At least nothing you'll ever notice or be able to determine w/all the other factors that effect vehicle fuel economy.

 

Where could I purchase a good underdrive pulley for an 03 V6 6spd?

 

next generation and the belt

 

They help, just get them

 

can't go wrong with Nick Boer's underdrive pulleys....

 

Keep in mind the full size light weight ones as well that takes all the risk to you ralternator out of the question

 

1. The difference is more noticeable in the lower gears, 1st & 2nd. a little in 3rd. With an underdrive its most noticeable in the higher RPMs.

2. With a full size you can use the stock sepentine belt, for the underdrive you'll need smaller one. There is no effect on the alternator with the fullsize, with the underdrive it will put out less of a charge. So if you have a system, bumping it loud at idle will be a no-no.

3. No +/- either way