I am putting a straight through Magnaflow muffler on it. I was thinking of taking off my Cat while i'm at it. Would this cause any harm to the engine?? No back/pressure, Fuel consumption, engine timing etc

Pro's and Con's ???

Nah it shouldn't be a problem at all. As long as your state doesnt have emissions testing. But your 83 is probably considered a classic by now anyways.

Yea it doesn't require a Emission Test so i'm good there, Should give off a awsome exhaust note! hopefully it doesn't lean or richen the ratio's out.

Do 944's need some backpressure though??

Ether way taking it off is gotta be a postive thing
for the engine> Less restrictive

if your worried about it put on a racing cat.