EGR and MAP

[Dave Williams]

 I have a 1/4" OD vacuum spider of copper tubing under my modified
Hilborn intake.  The Hilborn is an independent-runner manifold with
eight butterflies.  The vacuum spider handles the flow through the IAC,
provides a vacuum signal to the MAP sensor, and has a takeoff for the
power brake booster.

 I'd like to hook the EGR valve to the spider.  Is 1/4" OD tubing likely
to flow enough for that to work?  I could add a second spider just for
EGR, but I'm hoping to avoid that much work if I can.

 It strikes me there must be some code in the speed-density chips to
balance EGR and MAP signal, since vacuum will drop when the EGR valve is
open.