Hawk
The lazy answer is not radically different so not worth hunting for hoping to improve the performance of an earlier 2000 carb Beta. Of course using the cams from a 2000 in a 1600 Beta does give a performance lift and using a carb or IE inlet cam in a VX gives a performance increase but you would not want to fit the IE exhaust cam to a VX as all it gives is a big fuel bill.
I hope that helps.
Eric
Thanks Eric
my Beta has got an IE engine in (with twin 40s and exhaust) and I was just wondering if the engine was much different