center-lining cams???? wrong install???

[steve filipiak]

Hey everybody. I recently put some s3's in my 91 se-r, and since then
everyone's been telling me that i forgot to do this, and forgot to do that.
This is weird because i've never heard of anyone performing these tips when
putting s3's in (maybe some people do this stuff i've just never heard of
it). Well the mechanics that i'm getting tips from i guess build engines,
and they say that whenever you put cams in you have to center-line them for
best performance, and they say few people know that you have to do this.
What the hell's a center-line? They also say i have to get bigger fuel
injectors. The last thing they say is that when I set my timing to 15
degree's it doesnt matter because the computer will just set it back to what
it feels comfortable at. I searched about s3 installs and didnt find
anything about this. So my questions are:
1. Do i have to centerline my cams? Will i get better performance from it?
Where could i buy the tool if i have to?
2. Would bigger injectors help at all? Fuel pump + injectors?
3. Does the computer really play these timing tricks on me? With s3's and no
ECU i thought it was just 15 degrees and 89 octane.

Thanks for any help

Steve