Would it be bad to use 87 octane in my car? I don't think it's necessary, I dont have a turbo or any major performance parts on my car (intake, exhaust, header).

You need to use 91+ in the B18C1 which is what is in your GSR.

yep but if you use 87 the ecu is supposed to adjust to it.

yep but if you use 87 the ecu is supposed to adjust to it.

The only method the ECU has to determine that settings need to be adjusted is the Knock sensor. If the Knock sensor is telling the ECU that it detects detonation then it will dump extra fuel into the cylinder and pull some timming. Now this is bad! You don't want detonation, it will kill a motor faster than anything!
The reason the GSR needs 91+ is because of the compression ratio. I have friends who have used 89 but I would not trust it. Honda calls for 91+ in the B18C1 motor, so that is all I would use. :2cents:

I completely agree with whtteg. I always use 93 octane, premium gas whenever I fill up my '98 GSR. I tried 87 and the car seemed to react a bit differently, not as smooth-running. I just like the idea of burning more cleanly in the engine too.

if you want the most out of your car do what it says

plus it will only save you like 2 bucks anyway... why chance it?

yeah so if you fill up once a week that's 104 bucks a year
wanna take a gander at how much a replacement b18c1 engine would cost if it broke down due to poor quality gas
plus you car will run shitty as hell
use what it says in you dash
" Premium Unleade Fuel ONLY"