Re: HELLO! ITS BEEN A WHILE!
The spacer allows for the air flow to travel in a more linear pattern. You inlet plenum, the spacer, and manifold can all have an impact on it's effectiveness. The whole idea on increasing engine efficiency is to allow the air to flow freer through the system.Unless the spacer restricts air flow, at most it will do nothing for you.
You have to do some research and find out which designs work best with your setup.
Chewing on asphalt and drinking dinosaur wine