I have a 98' 200sx SE-R with timing set to 17 degrees, HotShot Headers, and a
JWT Pop-Charger. Right now i'm using 89 octane(shell), but I'm going to start using
V-Power which I think is 91 octane. My question is will I see some kind of improvement
in preformance in anyway after switching to a higher octane? And is it true that
higher octane burns more slowly, which should mean I would get better gas
mileage?
Thanks:biggthump :biggthump :biggthump

You should be running at least 91 octane when you advance to 17*. You can also go up to 19* but you need to run 93 octane to avoid the risk of detonation. You probably won't notice any difference by switching fuels.

anytime u advance ur timing u want to use a higher gas grade..detonation kills ur motor faster than running cooking oil in it...