? about Octane and Thermostat

[Voodooracer]

First ? is, do I need a lower thermostat with the tune? Second, whre I live octanes are as follows: 87, 89 and 93. So can I run the 91CAI tune with 89 of do I need to put in 93 and install the 93CAI tune? Sorry if these ?'s are trivial but this is all new to me with fuel injection and computer cars. Been strictly full throttle with carb for ther last 15 years. Thanks for any advice.

[mikel]

No need for the stat.
You should use the 93 octane with the 93 tune, using 89 with the 91 tune will lead to knock.

Thanks