Should I use higher octane with a vtec?

I have an 06 Honda Civic with a vtec engine. When I first got it, the way it drove made me wonder if it had a performance chip, but I've only been using 87 octane it and I've noticed a drop in the performance since I got it. So i don't know if it actually has a chip in it or if I should be using higher octane

You should use the octane rating recommended in the manual. Using a higher octane is a WASTE of money, and will not have any benefit. I haven't checked, but as the civic is not a 'performance car', I'm willing to bet the recommended octane is 87.

Use what the car recommends.

Yes