If you have your head milled and use low compression pistons, is it required to use premium octane gas or can you still use regular?

 

If your all motor you should be fine with regular. If your turbo use premium regardless of compression. What's your set up?

 

Why would anyone spend that much on head work to then install low comp pistons UNLESS boosting or spraying.







Short answer to your question, no. However, if you did all of that and increased the compression very likely.