I'm pretty sure it is that they started the 96/97 with the Vortec motor and starting with 96 they switched from OBD1 to OBD2.

1) Are there any other differences?

2) What is the difference between the vortec and the 95's motor?

3) What is better OBD1 or OBD2 and why?

Thanks guys.

1996 was the first year for the Vortec 350 and 1995 was the last year for the TBI setup.The 8th vin for the Vortec is an R and the 8th vin for the 1988 to 1995 350s is K.1996 was the first year for OBD II and some 1994 and 1995 GMs had an early version of OBD II.OBD II is better,you can actually get missfire codes and you can get a missfire graphic on certain scan tools.The codes are the same with GM,Ford and Chrysler instead of differant codes

The Vortecs have a Roller Cam, Better Heads and use CSFI (vs TBI) and got about 50 more HP than the TBI engine.

//2000CAYukon

You can tell if the cylinder head is of a vortec 350,has a sawtooth pattern.You can put them on the 1988 to 1995 350s,all you need is the special intake manifold for a TBI or Carburator setup.