The EGR basically has 2 functions, good and bad.
#1 When it opens it helps relieve head pressure, this is "good"
#2 Also when it opens it re-circulates exhaust thru the intake.
This is good for the environment but NOT so good for the engine.
In my opinion if you wanted to block the egr you should also consider opening up the exhaust from the exhaust port on the head to the tailpipe.
And install studs for the heads.
By just going with bigger exhaust from the downpipe-tailpipe, I don`t feel there is enough to relieve the head pressure when your just blocking the egr.
Sure you add big exhaust, but if you still have the stock exhaust manifolds,Y-pipe and stock downpipe there could be more head pressure built-up and cause possible bigger issues in the future.
The downpipe chokes down small which does not let enough exhaust pressure that has built up get out quick enough.
Several that add big power and have a lead foot, a blocked egr, find out eventually they need to install studs for the heads.
I feel if you just do the PCV re-route and forget worrying about whether to block the egr or not.
The PCV is very friendly to the environment but very nasty to the complete intake system.
By re-routing the PCV you will have a remarkable cleaner burning engine and exhaust, and leave the egr alone you won`t have the possible issue of to much head pressure.
I have a block-off plate that has been setting next to my computer monitor for 1 1/2 years. I feel unless I end up having actual egr issues that is where the block plate will stay.
I would not bother unless in the future you have a egr issue, then worry about it..
2007.5 GMC Sierra 3500 SRW "BLACK", SLT, C.C., 4X4, Loaded, DMax,Z71 Edge Insight CTS2, CFM Billet Valve Cover/Oil Fill Neck Breather, PCV Re-Route, Sinister EGR Delete, AirDog, ISSPRO fuel pressure gauge, BD Manifold, Diamond Eye down pipe & front pipe, 5" DPF(less)back exhaust with 6" tip, DIY Stock airbox mod with aFe Proguard 7 airfilter, Cognito NON Torsion Bar 4" lift, Cognito UCA's, Pitman/Idler arm support, Sulastic Rubber Shackles, Firestone Ride Rite, Bilsteins 5100's front/rear EFILive ECM tuned by ATP www.atptrucks.com
TCM tuned by www.duramaxtuner.com 2007 Yukon Denail "BLACK" 6.2 gasser DIY stock AirBox Mod, K&N, Airaid intake, EFILive TCM only by MJE Tuning
Last edited by D_R_C; 01-11-2010 at 01:04 PM.