Quote Originally Posted by echarleswhyte View Post
In my opinion, unless it is tuned and raced use what the manufacturer calls for. It may seem a surprise to many, but the manufacturers do spend lots of time developing their vehicles, if they say use 89, 91, 93, 105 oct then why mess with something engineared for that type of fuel. I know many will say the manufacturer has no idea what there doing and they know how to make and run a vehicle better, but for my money I just stick to what the owners manual says. My 2 cents worth take what u want from it
have you scanned a bone stock GT lately? they knock from the factory, especially when you run them on 89.