Originally Posted by psfred

The air recirc is mostly to keep the turbo up to speed on highway cruise to eliminate turbo lag and to dump boost under some circumstances to prevent overheating the trap oxidizer that you don't have (It also opens when you take your foot off the accelerator, same reason -- turbo spins but doesn't pressurize the manifold). It will increase milage a bit on the highway, but won't do a thing for manual shifts, you have to use your foot for that, as it isn't connected to the control linkage. Unless you have the computer system, it isn't gonna do anything anyway.

Peter