For that kind of power, you'll need a MINIMUM of 1500 W CONTINUOUS. That's continuous as in many minutes of operation with little to no recovery time. Some of the continuous ratings you'll come across will have fine print that specify a 30% or worse duty cycle (5-10 minutes on with 30-45 minutes off). That won't cut it with a compressor. Inverters with the kinds of specs you'll need will take up half the rear seat or more and really drain batteries and throw mucho heat. If you don't want on-board air, look for a gas-powered compressor.