Manifold Vacuum Experiment

About a month ago I decided to hook mine up on the big block.
I haven`t noticed any economy gains, but it did make it run about 5 deg. cooler, which will come in handy mid summer.
Last summer I experimented with a cool air/ram air system that some may look at it and say :wtf:. but lemme tell ya, that dropped my temps down on sustained interstate highway speeds by 5 deg. also. But, I now have been jetting up cause my plugs look like it`s running lean.