Thanks for the guide for the ratio, one more question,
Can I mix like 5 gallons at a time? or do I need to do it right before I am ready to use it? thanks
Mixed gas separates rather quickly. 2-3 weeks in a gas can and you will have a performance issue. I once put new gas in my tank, but left the old gas in my two spare bottles, and hiccupped and sputtered all the way home.
After 3 weeks, pour it in your car and mix a new batch.
On the octane, when the big ethanol switch happened last June, I did a lot of checking, with distributors and chainsaw repair shops, they were recommending 89 octane, MAJOR brand (BP, Amoco, et al.) There is a big diff in the refining from the majors versus the discount brands re: ethanol, where the consistency/blend was better. (It had to do with "on site blending" that the discount guys had to do).
Once that break-in is complete, you can try going down to 87 and make your own decision, based on how the engine performs.
An easy way to vary the speeds is to "pick a target", 2/3 throttle to the big oak tree, 1/3 to the end of the fence, 1/2 to the red mailbox at the top of the hill. You just don't want to get in a rut on the throttle speed, nor hurry the break in.
Make the engine "sing", by playing all the notes on the engine noise scale.
I know 2 guys who got in a hurry on the wide open throttling, and they can barely hit 20 mph, while folks who get that cylinder seated properly say the engine gets stronger/faster as more miles pass by, because they did that varying throttling correctly.
Our local Lowe's store sells a brand that comes in a squeeze bottle, enough to mix 5 gallons at 50:1 (I use the Japanese engines), a good oil at a good price.