Father and Son Duo Celebrate Improvement, Recent Wins at Watkins Glen in Shared Cayman GT4 Clubsport Entry

COLUMBIA, Md. (June 14, 2017) – For the Porsche Club of America (PCA) Club Racing Porsche Cayman GT4 Clubsport Trophy East series’ father and son TOPP Racing duo David and Russell Walker, a car isn’t the only thing the tight-knit pair share.   David, 68, created Pavecon, a Dallas-Fort Worth, Texas-based construction and pavement company…