The years of the MKI Scirocco are from 75-81 not to 84
And the MKII are from 82-92, but only 88 in the US, and 89 in Canada
An 8v motor from in the MKI would probably feel quicker than one in an MKII. My dad had a 77 and an 85 and I've heard from my mom that the MKI felt lighter and the engine didn't feel as stress out. COnsidering that the less options that are on a car the quicker it will be.
MKI Golfs are from 75-84. They should be fairly quick with the 16v motor in it since they are fairly light. Becareful though if you considering buying the way the engine swap was completed and done correctly.