I don't think that in SA there are any cons. As far as I am aware it is there for emmision laws and it is good for very cold countries.
There are two main problems with the EGR. One, is that by allowing hot exhaust gas to pass back in to your inlet system you lower the effective combustion achieved, as an engine will always combust better on cold dense fresh air. Secondly, the soot from EGR mixes with the oil vapor produced by the turbo and forms a paste which sticks to the inlet manifold and ports and reduces the flow, in effect causing the engine to strangle itself.
The Problem With EGR
EGR has become synomynous with:
Poor engine running
Lathargic throttle response
Carbon build up in the intake system
Reduced power
Increases of black smoke under full acceleration
Pros - are that less smoke gets pushed out your exhaust when you put your foot down(I have actually tested this) and your fuel consumption drops quite considerably(I also tested this and it definately makes a difference)
Its a very easy mod, remove engine cover, and on the right hand side there is a valve with a vacume hose attached to it that is connected to your inlet manifold, all you do is disconnect the vacume pipe and block it off( I did this with a small bolt) Then take a small piece of silicone pipe which has been blocked off too and connect that to the valve where the pipe you disconnected went, then all I did was cable tie these two pipes together to the nosel of the EGR valve itself to make it look all neat and thats it, took 2 mins to do this mod if you don't count taking your engine cover off.
This is what a EGR valve typically looks like and it doesn't take long for it to get to this stage. (This can't be good for your engine to breath in).
Sorry guys I kept deleting the post by mistake as something is wrong with my net at work and its causing my browser to do strange things.
