Anyone have a clue on how large a pipe I would need to plumb from my header if I were to use Vortec heads or motor and keep the EGR funtional. I was thinking something like a 1/4" pipe, but I don't have any idea how much exhaust gas must flow through it for the EGR system to work properly.

Please no one respond with either "just don't run EGR" or the "vortecs don't use EGR"....

Thanks

 

It has to be a little larger than that. More like 3/8" to 1/2".

 

Thanks again five7. Do you or anyone else have a pic of how this setup actually looks, i.e. a 96 up vortec equipped truck? I know the pipe comes off the pass manifold. Is it just a flared ended pipe? The reason I'm asking is I want to add some long tubes on my truck, but I'm thinking about running the 330hp Vortec crate when the 305 dies, and I would like to go ahead and weld a fitting in one of the primaries before I get them ceramic coated. Would I just need to weld something similar to an O2 sensor bung on say the #4 or 6 primary? I could then get them coated and screw in some kind of cap until I needed to plumb the EGR pipe.