can anyone tell me what size pipe the factory used for the intermediate pipe on a 91z28 single cat,are they 2 1/2in?after the cat?also the inlet and outlet sizes on my stock 91 cat,thanks,need a replacement cat to fit my new 2055's headers any suggestions?

 

come on now somebody knows what size astock intermediate pipe is on a 91 z28,singlecat setup?is the entire exhuast 2 1/2in?,need to know sizes help,need sizes of stock crossover to cat inlet,and cat outlet to intermediate pipe,thanks