removing rear hub - help!!!
 

Hey guys I'm trying to remove rear hub to change studs for longer ones, and it wouldnt come off, if anybody has any ideas why - pleas let me know

Assuming you have removed the rear disc / handbrake drum ...

They can be pretty tight. Use a hub puller. Hook the puller's legs around the square section of the hub carrier.

Usually you can replace the studs without removing the hub, depending on the length. As we don't know what year your 944 is, there are two hub designs, 82-85/1 (steel trailing arms) and 85/2 - 95 (alu trailing arms)
The early ones you can get the hub out without damagiing and therfore having to replace the bearings. The later one, you will need to replace the bearing.

All the information is in the workshop manual, either the Haynes or factory.

Of course, you could just get the "bolt-on spacer" that both Porsche and several other companies make.