In Phase 1 period, a series of engines consisted of; 1) turbo version and normal aspiration version of 2-valve twin-cam unit originally engineered by FIAT and 2) V6 and 2.5 liter turbo diesel jointly developed by Peugeot, Renault and Volvo.

i.e.turbo :DOHC 4-cylinder 1995cc turbo 165HP/5500rpm 26mkg/2500rpm
i.e. :DOHC 4-cylinder 1995cc N.A. 120HP/5250rpm 17mkg/3300rpm
6V :SOHC 90V6 2849cc 150HP/5750rpm 24.5mkg/2700rpm
Turbo ds :SOHC 4-cylinder 2445cc diesel turbo 100HP/4100rpm 22.1mkg/2300rpm

In Phase 2 period, a 4-cylinder engine was modified to a 16-valve one, and the balance shaft was equipped to obtain smoothness by canceling vibration in high revs. At the same time, production of the original 2-valve models was continued, so there was a wide selection of engines during this period.

i.e.16v :DOHC 4-cylinder 1995cc 150HP/6000rpm 18.8mkg/4000rpm
turbo16v :DOHC 4-cylinder 1995cc turbo 185HP/5500rpm 32.6mkg/2500rpm

An extravagant Ferrari engine was arranged for 8.32, which means 8 - cylinder 32 valves. It was developed on the Ferrari 308 Quattro Valvole engine, the 90crank was changed to 180, and it was modified to lower speed torque type which is less vibrant than the original.

DOHC V8 2927cc 215HP/6750rpm 29mkg/4500rpm
DOHC V8 2927cc 200HP/6750rpm 26.8mkg/5000rpm

8.32 disappeared from the Phase 3 variation. PRV V6 was replaced by Alfa Romeo 3.0 liter V6 engine. This V6 unit was the power unit of Alfa Romeo 164, however the one for Thema was SOHC 12 valves only and 24 valves was not arranged. All aluminum block Alfa V6 generated sensual sound and the best feeling. The head cover with crystal paint together with the air chamber was accommodated to the LANCIA style, and the engine sound was milder than the original Alfa version. The turbo version was also modified to achieve max 205 hp.

3.0V6 LS :OHC V6 2958cc 175HP/5500rpm 24.9mkg/3750rpm

turbo16v LSiPhase3j:DOHC 4 1995cc turbo 205HP/5750rpm 30.4mkg/3750rpm