I have searched a bit on the forum, and cannot quite piece together the answers I am looking for. Here is my current mods:

180 T-stat (not drilled)
Replaced air filter with K&N filter (have not modified the box)

One of the pulleys on the SC belts broke. I am planning to replace them all, but since I have had the quick change pulley system in my garage for about 3 years, I figured why not replace that with a 3.5" pulley as well (I have the proper tool). So, here are my questions:

1. Should I put a 3.5" pulley with my only mods listed above? If no, what can I easily do that will allow me to run the 3.5" effectively (I am just not ready to do the custom air intake yet)?
2. I believe I need the 4060715 belt for this pulley, is that correct?
3. How will going from stock pulley to 3.5" effect gas mileage, under normal driving (to and from work, vacation trips etc...) conditions?
4. Lastly, to create a custom air intake I have seen some posts were it is mentioned to ideally use a 3" aluminum tubing. Would it be wrong to use a 3.5" tubing (if it can be found, no luck for me yet) to allow more air flow into the engine?

These are the items we recommend as initial starter mods:

http://www.intense-racing.com/Mercha...roduct_Count=2

We offer 3.5 intake tubing here:

http://www.intense-racing.com/Mercha...oduct_Count=20