Ways to make these cars into street legal drag cars?

Save the racing for the race track. The street is no place for racing. You place innocent bystanders at risk. I suggest making a trip to your local race track. While you are there get yourself a copy of their rule book. Here's why you want to race at a track instead of on the street. People watching the race will be protected by fences, guard rails, and barriers. The only people at risk will be the participants. When racing, things can go horribly wrong in an instant. There will be an ambulance on site with EMT technicians. Help will be there in seconds. How long would you have to wait for help when street racing. Do you expect your buddies to help? No, they will be getting the heck out of there so they aren't caught. When racing on a track there will be a rule book and officials to enforce the rules. This does a couple of things for you. First, there will be rules regarding safety equipment and vehicle construction to give you a chance of surviving a crash. Your vehicle and equipment will be inspected. Also, a rule book will help level the playing field. You will be racing against equally prepared vehicles so you have a fair chance. When racing on a track you will have some competition. Vehicles will be classified so you will be racing against other vehicles with similar capabilities. Most tracks will have entry level classes for someone who is starting out and on a budget. You won't have any trouble finding anyone to race. You could be on a track with 20 or more of your friends. You won't be breaking the law. On a track you can go as fast as your abilities permit and not have to worry about huge fines, high insurance rates, or ending up in jail. There will be lots of spectators. Who knows, you might even end up with a few fans. It's kind of cool to have someone come up to you and ask you for your autograph. On the street the only one asking you for your autograph is the cop having you sign your ticket. Get used to public transportation for a long, long, time. There is no money in street racing. You will be abusing your car and breaking parts with little to show for it. When racing on a track there are opportunities for sponsorship to help with expenses. Most racing classes pay money. This will also help with expenses. You may not come out ahead, but you will do much better than what you would do on the street. As for which car to get? Check out your local race track. Many times you will find cars for sale. This way you won't be re-inventing the wheel when building your first race car. You will have something that has already passed inspection.