Originally posted by Z1 Performance
I would completely disagree with what Speedwagon says. If the ecu is programmed to see 87, assuming you have not modified the car significantly via bigger cams, increased compression or some form of forced induction, the higher octane fuel will do absolutely nothing for you performance wise.
All modern gas has detergents in it (more marketing hype, sorry to say). If you believe that the big oil companies don't stretch the truth, then your being way to kind to them. Sure false advertising is illegal, but they are not really telling you anything except it has detergents in it. Nowhere do they ever say that their 93 octane has more than their 87 or 89 octane.just that the 93 has it..big deal.
What WAFlowers said is right on the money...its trail and error. My Legacy loves Shell and Mobil, and is not so fond of Amoco..why? Who the hell knows...my ZX which has around 600 HP runs just great on Mobil 93 for the street, and I have a tank of Amoco 93 in it right now and the datalogs all look the same.
If it runs better on the 89, thats cool....maybe now try some different brand 87's and see what it does.
Allow me to retort: (just had to use that word
Actually, Mobil's website does state that their premium fuel has more detergents in it. I only state Mobil, cuz that's all I have looked up in the past.
As for your car not liking Amoco.. that would be detergents/additives. Because, all the gas is the same. It is more economically feasible for the petroleum manufacturers to make the gas to standard, and put it all in the same pipelines to ship it wherever. Amoco, Mobil, Shell all put some 87 octane in on one side, and pull some 87 octane out the other. That doesn't mean they pull out THEIR 87 octane, which is why there are standards. The differences lie in the detergents/additives after they get it to the regional location.
And, it's quite possible they do stretch the truth. But, from the research I have done, I cannot find any good reason to waste my time trying to prove them wrong. So, I will go with what they say. If my car runs better on 89 than 87, and Mobil instead of Amoco.. well, the proof is in the pudding then.
And just so I know, which points are you disagreeing with? You can't possibly be disagreeing COMPLETELY.. cuz we aren't saying the opposite of each other here.