You have to add the weight of petrol to that (let's say 80 liters or 60kg). That's partly compensated by the weight of the electrical engine (70 pounds = 30kg) that you have to add to the Tesla.
=> all else being equal, the Tesla will be heavier.
However, 'All else being equal' currently is a bit debatable, I think. Tesla seems to have optimized further for weight than conventional manufacturers do.
A typical engine of a comparable car weighs ballpark that in pounds (http://www.team.net/sol/tech/engine.html; links to better data welcome)
You have to add the weight of petrol to that (let's say 80 liters or 60kg). That's partly compensated by the weight of the electrical engine (70 pounds = 30kg) that you have to add to the Tesla.
=> all else being equal, the Tesla will be heavier.
However, 'All else being equal' currently is a bit debatable, I think. Tesla seems to have optimized further for weight than conventional manufacturers do.