V=Flint MI engine plant
09=Sept
09=9th day
TWZ=1978 350, conv.cab truck, L LS9, 165 HP, 4 barrel carb, K-10 to 2500
(from:
http://www.nastyz28.com/gm-chevy-cod...s-suffix-8.php)
By the way--GM used the LS9 designation for 69-up truck 350's for a while. This is different from the LS series of engines that also have an LS9-code engine.