Originally Posted by y_p_w
Originally Posted by painfx
So what is it with Sunoco Gas station having 4 different flavors - 87, 89, 91, and 93. Why not eliminate the 91, if already have 93 like the other gas station does. I don't see what is the point of having 91.
Is there a difference from 91 to 93?
2 octane points is a huge difference. I know it sounds like a small number, but it's a massive difference in terms of potential performance. For instance, in a Honda Civic Type-R the power rating is 306 HP with 91 octane. I remember seeing some video where the operations head of the Honda factory in Swindon went for a test ride in someone's new Type-R. He mentions that with 98 RON it was rated at 316 HP. I don't think the guy taking delivery quite understands the difference between RON and AKI, or at least didn't quite understand at the time.
I only wish we could find 93 octane around here. There are quite a few engines these days that are tuned for maximum performance with 93 AKI. If there's anything higher than 91 AKI, it's made with street legal 100 AKI octane unleaded racing fuel.
91 to 93 is two numbers, which is an order of magnitude away from two points.
TEL and BTX are available on eBay and will push your octane past 100, never mind a piddly 93