It's getting to be down right diffifult to find pure, 89 octane gasoline in central Illinois (land of the corn cob, LOL). Most everything has got 10 percent ethanol added to increase octane.

1. Am I at risk for shortening the life of my engine if I use this stuff?

2. What is it that Mazda is warning about in the manual? Full ethanol fuels (ie >20 percent blend??)

3. What will happen if I use gasoline with 10 percent ethanol blend?

 

You should not be using any methanol or ethanol mix that is more than 10% blend (90 percent gasoline- 10% alcohol). The problem is related to drying out of the fuel lines, and seals, as the alcohol tends to dry them. Adding a little TC-W3 based pre-mix (100-1 ratio) will probably help if you are forced to use a blend.

Why are you using 89 octane? Is this a modified Turbo?

Non-turbos produce more HP with lower octane. Ideally 87.

 

Duh, the engine seals. Why couldn't I figure that one out for myself?

Oh well, the reason I use 89 is that it realy does seem to give me more HP and a smoother running engine. That's subjective, of course. I'll go back to 87 for a while and see what happens.

 

placebo affect. Marketting that actually works...

 

I thought with ANY turbo car.. you want to use higher octane so you don't detonate...

Oh, and higher octane doesnt make more HP... all the higher octane does is increase the flash point of the fuel (higher compression engines and/or turbo/SC'ed vehicles use it for this reason).

It probably does make your car run better though.
Oh, and you know how they advertise that the 91/93 etc etc has all these cleaning agents? Well so does 87 haha! Its a law.. they have to put the same **** in there

 

Generally speaking with 'pump' fuels the higher octance you go the lower the energy content, so you want to use the lowest possible octance rated fuel that your engines needs to prevent detonation..

Your right higher octane doesn't make more power in itself, but if you use a higher octance you can usually get more power from running slightly closer to the (new) detonation threshold.