I don't know how they would work on a Fuel Injected Vehicle???
Fom my understanding you need to hook up a coil by your exhaust and weld some bungs into your pipes to fit spark plugs.
You rev it to 3000rpm then press a button. The button cuts spark to your engine and gives it to the coil out back. Your engine stops burning fuel and dumps it out the exhaust to get ignites by your sparkplug/coil setup out back..
There are two problems I see with this..
1) Your cats are going to get red hot catalyzing all the unburt fuel from your engine. Eventually you'll ruin them. So you have to cut the cats off..
2) I don't know how you would get a FI vehicle to cut out and dump that much fuel into the exhaust..
Maybe I'm way off base, but that's what I understand..
Riley