Should be getting my 8 back home this week and in several minds which way to go with the project - and don't want to start down one route only to change my mind as that is very expensive.
Want the car to have a minimum of 300 bhp per ton with modern brakes and suspension. Target weight is 750 kgs which means a reliable 225 bhp is the minimum requirement for the engine.
My 3 options under consideration are
1. Gordini/5GT hybrid turbo engine with modified/rebuilt gearbox in standard casing.
Pros - cheapest option, already have alot of the required parts, well proven conversion (as an atmo anyway!), keeps car fairly period and originalish.
Cons - Engine fairly stressed at target power, gearbox expensive and unreliable at this power level, clutch will probably have to be specially made.
2. Megane 225 complete transaxle. Basically have a specialist fit the entire running gear from a Megane in the back - plenty of 205,s , GT Turbo's etc have done similar.
Pros - Reliable modern powerplant with lots of tuning potential, very strong. Still a Renault engine, parts availability.
Cons - Major surgery to fit
3. Mazda rotary turbo engine with UN1 gearbox.
Pros - Huge power potential, parts to mate engine and 'box are available, engine small and light.
Cons - Still a tough fit, fuel consumption, what are my insurance company going to make of it! Non renault engine
Any other suggestions appreciated.
go for the megane engine 
