When rebuilting the engine, using modern high specifications for parts and tollerances will free more power from the original engine. Cars fitted with the Traction Avant engine can use the DS derived engines as used in later H vans.
In the Traction several engines were used.
The Perfo 11 engine has 56 bhp.
The 11D engine has 63 bhp.
So if you don't have a 11D engine, this would be a good place to start.
The big advantage is that no other modifications are needed which maintains the originality of the car.
When more power is wanted, a 1911cc ID/DS engine can be fitted.
This can be done in combination with the 4 speed gearbox, or the gearbox can be fitted without the DS engine.
On the 15 Six, a later type DS engine and (5 speed) gearbox can be fitted.
Up to 130 bhp should make a very fast Traction.
All the information you need can be found on the following pages:
First a Maserati Merak SS engine can be fitted. This gives a lot more power then the Citroën version.
SM World (California USA) offers engines up to 300 bhp.
Interesting example cars
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