If you have clicked on this page, We cannot stress enough how cool this tune is.  If you have ever logged your car using the Cobb AP. 
If you have not, check this page for what to watch for https://www.getmtuned.com/cobbgaugelist. You will see that with fuel's like 91/93 it's tough to stay away from seeing feedback knock. The FA20 is a fantastic engine, but fuel quality dictates just how great it can be.
 
A Stage 2 93 Octane FBO FA20 Makes say 285-320 with 93 Octane fuel and a good tuner...  Why is this tune cool? On a STOCK FA20 WRX..  Meaning you have no mod's You can see between 320-330HP depending on elevation, condition of the engine.
 
If you go Stage 1 Meaning you add an intake You will see between 300-340WHP.
 
If you go Stage 2 by adding a CATTED J pipe to the intake and remove restrictor pill or install 3 port 330-375WHP
 
Pushing the fuel system past 375 is a per car basis and not all HPFP support this. Higher miles, in-tank pump performance, and local fuel quality.
 
Now, that does not mean we do not suggest supporting mods.
 
We suggest the following to be added to any of the tunes for the max performance.
AOS
EBCS
FRESH PLUGS( Every 30k is what we suggest)
INTERCOOLER UPGRADE
BPV
 
This tune is great for anyone who is looking to get the most fun out of the WRX for the money. A E60 Tune on a other wise stock wrx from us WILL beat your friends 93 Octane Stage 2 car. 
 
How will you Mix it? Scroll on over to :https://www.amazon.com/Etched-Ethanol-Content-Tester-Gasoline/dp/B07NMV8WGP/ref=sr_1_9?keywords=ethanol+test&qid=1582747580&sr=8-9
Grab your self a cool little tester.  Using your local ethanol station test your content. 
 
Input the ethanol content and your tank size into our calculator Here
 
If your using a glass tester we have found them to read about 5% high. We suggest factoring that into your mixture.

So if you tested your local station at:

60% Run straight.
70% Mix 1 gallon of e10 91/93 for every 5 gallons of E70
80% Mix 2 gallons of E10/91/93 for every 5 gallons of E80
90% Mix 3 Gallons of E10/91/93 For every 5 Gallons of E90.
 
It may be a little confusing at first but after the first few pull's you forget about that. The mixing becomes easier.  Did we mention..  320-330 WHP on a STOCK car. And up to 400HP on a FBO car ( This would be pushed to the limit).