Premium Vs. Mid-grade Unleaded Gasoline

[humanoid]

I'm in the process of acquiring a 1998 GS300 in very good condition. I'm pretty sure it takes premium unleaded as did our old '93 GS. The question is can we get away with using mid-grade (89 octane) rather than the super unleaded? I know that I'll probably be sacrificing some performance, but will it harm the engine in other ways? Other concerns I should be worried about?

[fordsvtmfl]

You could get away with it if you really need to save about $1.50 a fill up. some ppl say it might start knocking...but i dont think it would really do anything...BUT there is a little flaw in your thinking, and that is if you use regular or mid grade you will get about 1-2 mpg WORSE, and if you figure that out... (this is losing 1 mpg with mid grade based off of 3.90 a gal for mid and 4.00 for premium and 1 mpg difference.) you would spend $65 a fill up with mid grade and $63.16 with premium. so in other words, it costs you more to be cheap, about .35, and not to mention performance.

hope that helps (and sorry if i came across rude about the cheap thing...didn't mean it. :)

[2JayZ]

The stated requirement for the 98 2JZ-GE is 91 octane. If you use 87 you'll definitely get octane ping and lose efficiency. Every once in a while I'll fill up with 93 octane and the car seems to run even better than with the 91 octane. I don't have scientific proof, but my senses tell me there is a definite difference. I also avoid fuel containing ethanol unless there is absolutely no other choice.

[2JayZ]

You may want to try this -- run your tank down to reserve and fill 1/2 way (10 Gallons/ 37.5 Litres) with 89 octane. Drive around a bit and see how the car performs. The 89 is only 2 points from the recommended 91 so you may get away with it. If the car runs crappy you can go back to the gas station and fill up the remaining 10 gallons with 93 or higher octane and your tank's final octane will resolve at 91 or higher.

[humanoid]

Thanks for the reply, folks! I'll give those suggestions a try when I get the car, thanks again!