My compact SUV petrol engine and turbo stutters around 60mph. It's okay if I'm stepping on the accelerator about 95% and when floor it from rest stage. Do you think the engine needs more power/torque only when floored at 60mph or for both, also when floored from rest?
If you are having an issue with the engine sputtering at highway speeds, it may be related to your fuel system. I would recommend having your fuel system checked by a qualified professional due to the fact that gasoline is extremely flammable and potentially unsafe. This inspection would go over the fuel pump, fuel filter, fuel lines, fuel hoses, fuel rail, fuel pressure regulator, and other fuel system related parts that may be specific to your vehicle. This symptom is commonly caused by fuel system issues, so checking the fuel system first would be my best recommendation to have your sputtering issue properly diagnosed.