The gases expelled from a turbine are not worth a whole lot as thrust. Most of the energy has been used and tranferred to the power turbine. do a search on google under turbine powered cars. Lots of info. One of my favorites was this one....way back in the lete 60s:

One of Burt's most interesting experiences was his involvement with the construction of a turbine powered race car that was eventually run at Indianapolis during qualifying.
In 1967, engineer and STP team owner Andy Granatelli brough a revolutionary new turbine-powered car to Indianapolis. Driver Parnelli Jones dominated the entire field for the majority of the race on race day. During the last few laps, a small $6 bearing failed, and the turbine died. With four laps to go, A.J. Foyt passed Jones for the lead and eventual victory . However, the turbine had demonstrated its potential.

Jack Adams, like Granatelli, also saw the potential of the turbine, and had begun construction of his own turbine-powered Indy car. Adams had been a pilot for Delta, and decided to retire when the company transitioned from prop-driven aircraft to jets. He then created his own business in Memphis, Tennessee, dealing in aircraft sales.

Adams had approached RFRL engineer Glenn Bryant about building the turbine-powered race car, and Bryant agreed to participate. Stan Burt would be involved in the entire process as well, and construction of the car took plave in Bryant's basement.

The car was designed around a GM Allison 250 Turbo-Shaft turbine engine, capable of revving to 33,000RPM's. The engine had originally been designed for use in helicopters, but the Adams design team turned the motor sideways and re-plumbed the oil lines to get it to work in the front engine-mounted, 4-wheel drive car. The chassis was an all monocoque construction, and the suspension and wheels were originally faired in. Unforunately, this would hinder any attempts at repairing broken components during a race. The cockpit had an aircraft-like appearance, and the driver was virtually laying down. The cockpit tub was supported by balsa, and the exhaust from the front-mounted turbine ran beside the cockpit, although it was well insulated. The car was extremely aerodynamic, featuring boundary recovery on the tail. The Indy officials would ban the use of the rear wheel fairings, and the car ran without them.

The Adams team was originally sponsored by Wynn's