I have a feeling you were not actually on TDC when you put your timing tape on so your timing is not reading correctly. Verify TDC on compression stroke and see what the pointer is indicating. If it is not reading zero you have found the problem.
Alternatively you could advance the timing and see if the vacuum reading improves. If it does then proceed with the above. Your current reading of 8 is way low. Check for vacuum leaks also.