Simplify the following text for a Grade 8 native English-speaking person.
Original: A special endurance version , the DFL , was then developed in two versions : one with 3298 c and the other with 3955 c. Whilst the former version soon became known for its reliability , the latter version was a step too far and is largely remembered as a failure .
Simplified: A special endurance version , the DFL , was then developed .