What car is this?

My brother had this car.

I think it was a Cyclone, but I am not sure.

I think it had a 390 c.i. motor.

When you drove it down the street you could see the needle for the gas gauge needle moving towards empty.

But it was rather fast.

The Cyclone was the performance model of the Mercury Comet, and if it came with the 390 engine, then it definitely must have used a lot of gas.

Correct. Mercury version of the Ford Fairlane GT. A high school buddy had one.

Looks like that might be around a '66: