I was told that if you have a 1.7 Case that 2.0 heads won't fit right .. They have to be machined to work .. also that 1.8 heads on a 1.7 case is a better fit .. Also VW makes a Cylinder head that is have the cost and less work to fit up to a 1.7 case ..
I'm running into a lot of different guys with a bunch of different options to rebuild a type4

Things I'm thinking on changing

1) The Heads

2) the cylinders and Pistons

3) the cam

So with these 3 things what is the best combo ... ??

All cases are basically the same, differences are the crank, rods, pistons and barrels.
Best setup is a 2.0 crank and rods, 96mm pistons and barrels with 2.0 heads.
2056mm.

totally agree and then add stock 2.0 fuel injection!!

and head bore, 1.7 is smaller, 1.8 and 2.0 are the same.

Thing is there's hundreds of ways to skin the cat. You've already be given several answers on other threads, time for you to make a plan of what you want from an engine,your skill level and how much you want to spend.

Once you have that plan ask question, but stick with the base of the plan.
I wouldn't worry about cam till you have your bottom end, intake and heads decided upon.

dp

As everybody has said, the cases are basically the same. At least as far as fitting the top end pieces goes.

The difference you may have heard of is that the registers, the part where the cylinder fits, is 100mm on the 1.7 heads. On the 1.8 and 2.0 heads, it is 105mm across. So the 1.8 and 2.0 cylinders will not fit into 1.7 heads without some machine work, and the 1.7 cylinders would need some spacers to fit into a 1.8 or 2.0 head.

There are other differences between the heads (valves, ports, the 2.0 spark plug location, chamber shape and size, etc.) but the above is what affect cylinder fitment.

--DD