Is premium fuel a must in the Z?

 

no. it'll run on 87, but you'll lose performance. I'd use 91 -94 octane alwaysif at all possible. I'd only use less if Im almost flat broke with enough money to buy 1 gallon of 87with my tank on E... my friend ran his on 87 and it really seemed down on power.

 

I wouldn't use anything less than 91. You'll get pre-ignition which will cause the knock sensor to pull timing killing your power. If the PCM can't pull enough timing, you're headed for busted ring lands.

 

I actually noticed getting better gas mileage using 93 because timing wasn't being pulled.