i was just wondering what a variable power boost dial and does it work or is it a scam. and can anyone give me some pros and cons of this item?

 

If I have heard of this, maybe I could answer your question. Do you have a link or url address?

If it is a dial/gauge that you can place on intake and exhaust valve cams, providing that it fits on our engines, then yes, it is a tool that you can use to adjust power curve on your engine.

Do some research/study on "degreeing a cam" to find optimum valve open and close points.

 

Could it be just a MBC (Manual Boost Contoller)?

If so they are ok, but not the best thing to do to raise your boost. Just like changing the wastegate isn't a good idea.

Best idea is to get an ECU upgrade. Look at my other post I made in your thread for websites for chiptuners.