The last gas question

[Ace]

Someone please show me where Toyota indicates that the U.S. Yaris or the NZ series engines were designed for 87-octane gas. Or that it runs better on 87-octane gas.

The Smart requires premium gas; Yaris has a higher compression engine.

[1stToyota]

Originally Posted by Ace

Someone please show me where Toyota indicates that the U.S. Yaris or the NZ series engines were designed for 87-octane gas. Or that it runs better on 87-octane gas.

The Smart requires premium gas; Yaris has a higher compression engine.

Simple. Factory tuning. Ever heard of canned tuners like Diablo, SuperChip...? Even they can be tuned for what octane you want to use. The Smart is tuned for premium and performance will fall off if lower octane is used, sort of like my GTO...I could get by on less than 91, but car was tuned for 91. Unlike the Smart, the Yaris isn't tuned for 91

And on page 384 ('08 manual) it says **87 octane or higher**
so I might try mid-grade for a while and see