JustGoWithItHmm, it normally doesn't make much of a difference. What brand model car do you have?
THEDIRTYBUBBLEIts a Mercedes station wagon from 2005
japanadaUnless youre running a 500hp turbo monster, its not gonna make that big of a difference. Not to mention that you still has gas in the tank/fuel pump/gas lines so the 87 wouldnt have been burning right away when it took 15 seconds to get to 20mph.
My VW calls for 93 and Ive run 85 in a pinch with no side effects minus a mpg or two drop in gas mileage.