Eastwood described the Fast and Furious actor as a "huge role model and influencing figure".
"Paul was a close friend of mine... He was an older brother to me. For me to be able to add to the F&F story, Paul's story, and the FAST family is like a dream come true."
Eastwood remained tight-lipped about the film but revealed his character will operates under Kurt Russell, a "total childhood hero of mine growing up".
"Very much looking forward to learning a thing or two from such an original and cool guy," Eastwood added.
Fast and Furious 8 is due to hit theatres on April 14, 2017.