You have mentioned on this thread that you work on upto 8 cylinders. It might be worth depending on what type of Scope you decide to go for i.e. 4 Channel or 2 Channel to take a look at the Mixmaster.
This will allow you to look at the 'Secondary Signals' on upto 12 Cylinders at once.
If you take a look at this forum thread you can see how the Mixmaster works:-https://www.picoauto.com/support/post23712.html?hilit=mixmaster#p23712
Also the product page can be found on the following link:-https://www.picoauto.com/mixmaster.html
Lee - Automotive Technical Specialist