Although Dillmann acknowledged he was spending a long period in junior single-seaters - having raced in the Formula 3 Euro Series in 2007, won the German F3 title in '10 and then been around the GP2 scene from 2012-14 - he said still feels he has a point to prove.
"I thank Adrian Valles for providing me with this great opportunity," said Dillmann.
"After the test we had together at Alcaniz, I'm sure we will be able to enjoy a successful season.
"The car is one of the best in business, it's really quick and thrilling and I think I still have some unfinished business in single-seaters.
"I never managed to be in the right place at the right time, but with AVF I feel I'm in the right position to score the results my abilities can do and reverse my fortune."
AVF has already completed its F3.5 V8 driver line-up, having announced Alfonso Celis Jr as its first driver last month.
"Together with Celis, who grew up consistently race after race in 2015, I think Tom will form a great line-up that will allow us to aim for the top in every single race," said Valles.
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