In the owner manual for my 2003 z it says do not run any fuel less than 91 octane. Is this true or can I just run regular

 

Welcome- and yes, the VQ in your Z requires premium unleaded for maximum performance. If you can't afford it, get another car.

 

The difference between 87 and 91 is about 20 cents. Thats around 2.50 a fill up. Thats around 120 bucks a year on average. If you cant afford 120 a year on maintaining your car with the proper fuel, you need to buy a prius.

 

I think moped would be more suitable