When my oldest was 18 he spun out a 87 Lincoln doing 5 over the limit around a curve. Wiped out a sign, dented the trunk 16", popped two tires off the rims.
When I was 18, I was racing my Dad's '66 Mustang convertible at 125mph down the main road going out of town. Like as not, your Dad was doing something like that, too. We all have.
So, advice about just stick 30" tires on it has a background story, just like trying to "convince" your parents. Umm, like father, like son, I just bet he'll eventually tell you about the stunts he pulled at your age - and doesn't want you to do the same. It was all based on the fact that young men age 16-24 have horrible risk assessment and decision making skills. It's a fact, and the insurance companies charge dearly because of it.
Now, had you saved up and bought the car, built it lifted, and had it parked in the yard before your 16th birthday, we might all have a different view. But like my brothers in law, it didn't help a bit - they both wrecked their '55 and '57 Chevy's.
There are no guarantees in this world. I wrecked my own '66 Stang more than once. "Speed costs money, how much can you afford" is more than a old cliche.