We have a local shop that builds that kind of stuff. They had a Mitsubishi Eclipse with a jet - dude said he could light the jet (at highway speed) and it was ready for use in 15 seconds. He also claimed 80-180mph in ten seconds. He offered a ride, I declined.
FYI, he finally starts the jet engine at about 5:22 into the video. And unless I missed something, they didn´t even show the car in motion using jet power