The 100 miles per hour as a goal is not too difficult. Make sure you start with a car that could do this safely with the internal combustion engine.I want to make an electric car with the following specs
Goes about 200 miles
top speed of 100 miles an hour (maybe)
The 200 mile range is a more difficult task. Range goes down as you add weight. So you can't just keep adding more batteries to increase the range. The usable range for Lead Acid is about 15 miles. This is not the day one range but the distance you can go when they are about half done. If you double the weight of the batteries you don't double the distance you can travel. The sweet spot for LiFePo4 is about 60 miles on a conversion. You can push this up to about 100 miles without imparting too much weight penalty. When doubling to 200 miles you tend to run into both weight and space issues. This is where Tesla has an advantage in that they planned the car around the battery. A conversion does not have this. You will spend a lot of money on batteries to get to 200 miles. Even if it scaled directly with dollars spent you will be looking at something over $30000 for just the batteries. I thought about pulling a range extending trailer to get to 350 miles total. Turns out this is about $60k in just batteries to get there not counting what is already in the car. So not at all practical.