hey guys
have a few questions from a person who doesnt know what hes doing at the best of times

I plan to upgrade my intercooler from the stock wrx one, still going to go with a TMIC though, would the car need a re-tune afterwards or is it just a simple swap over?

Going to do an oil change this weekend which Mobil 1 oil would be best? (02 WRX with 3" TBE & verso) I mean as in 5-50w or 10-30w or ....... ?

If some of you read some of my previous posts, you might be aware that I need to replace my alarm module as its screwed. Ive decided to go with the stock alarm system for now. I was wondering, does the alarm module need to be encoded, or can I just buy the module from Subaru and fit it myself?