Art deco era race cars : A set of 6 drawings

A fantastic set of 6 drawings  depicting race cars.
Stunning quality. Hand drawn. Not litho or any recent edition.
Hard to say how old they are. Paper is yellowing. I would say 1930/1950.
I have made few researches about the artist but cannot find who he is.

6 pieces are signed.

over all dimension 40.5cm x 31cm (drawings about 20 x 29)

Price is for 6 pieces.