Pigpen - I still consider myself a novice here, but I'll see what I can do to help. I placed a K&N filter in the stock airbox as soon as I got the truck home from the dealer. I actually ordered it before I bought the truck and had it waiting for the truck to arrive. I used it for over 20,000 miles before I learned of the problems that others were having. I did not know about this until I was introduced to the TDR. I did some research here and decided to get the aFe stage 1 kit with the PG7 filter. I have before and after pics in my reader's rigs section. I am very happy with the system. Fortunately, I had no dirt or oil on the intake hose after those miles on the K&N. I cleaned the filter about every 10,000 miles. I plan to do the same with the aFe. I'll try to give an introductory answer to each of your questions.
- What is the difference between a Stage 1 and a Stage 2 AFE?
I remember reports from previous posts claiming 1200 cfm for the stage 2 kit. The aFe website claims 820 cfm for the stage 1. The PG7 filter is supposed to flow about 10% less for each kit. The stage 2 kit has a torque tube that replaces the stock intake tube which should provide smoother airflow between the filter and the turbo. Arguments have been made as to benefit of this increased airflow on a relatively stock engine. Below are links to each of the filters on the aFe website.
Stage 1
Stage 2
After I bought my kit, I stopped researching the filters. I did a quick search just before replying so I would have less chance of passing on bad information. I'm sure a search will do you more good than I can on a comparison of these two. The clearance problems with the stage 2 kit that other members mentioned also kept me from buying it. It will not fit with the Banks brake. I got this in an e-mail from aFe.
- What is the Scotty II?
The Scotty system pulls cold air from the cowl area into an enclosed airbox with a high flow filter. I believe that the aFe filters are available for these systems also. One of their systems can pull from the cowl and the hole in the fender that feeds the stock airbox. I have never seen one of these in person, so I can't help out too much with it.
- What cowl hole are you all talking about?
The one you will have to cut if you want to pull air from the cowl. I found pictures of other members' setups after a search using only the term "scotty".
- Does the AFE come with a screen pull over filter that can be taken off and is this necessary to have?
I think you are referring to the pre-filter. This is an additional layer of material that can be placed over the filter to remove larger particles before they get to the filter. Opinions vary, but if you keep your filter cleaned and oiled properly you won't need one of these. I know they are available for the stage 1 kit, but I do not know about the stage 2.
I would highly advise that you do some research before you shell out good money for any of these. Many people use them but many others don't. Another option is the BHAF (big honkin' air filter, I believe). It is a giant paper filter. Do a search on it and at least give it a look before you decide. If you go with the aFe stuff, consider buying it from Geno's. Their customer service is second to none.
I used the word "search" as many times as I could to give a subliminal message. I ended up looking for hours and hours before I felt that I had enough info to feel comfortable with my decision.
Good luck. If you have more questions, I'll do my best to help answer them.