benefits of EGR removal?

[changaroo]

i see that some members here have removed their EGR... what are the benefits?

i thought there was no HP gain from this? just keeps the IM clean?

[IDon'tKnow]

I'm removing mine to clean up the engine bay a bit and keep the intake side clean. It's purely an emissions device and removing it doesn't provide any performance benefit.

However, I would argue that .5mm thick carbon buildup on your runners and valves is a performance detriment; so if you are building and engine and you are porting the intake manifold and head you might be interested in keeping your work clean by eliminating the EGR.

That's just my $0.02, I doubt there is any reliable reference data for either side of the argument.

i see that some members here have removed their EGR... what are the benefits?

i thought there was no HP gain from this? just keeps the IM clean?

[changaroo]

will the car still pass emissions? with it removed?

[IDon'tKnow]

I doubt it; I guess it depends on the state and their inspection methods. Some states don't have emissions inspections at all; for example AL where I was living when I started my project.

Also, I think that most states have antique and classic car exemptions for vehicles older than 25 years. My MR2 is an 86 model. I'll try and register it here in VA and if that doesn't work out I'll simply register it with a family member's address in another state.

[paton]

The EGR is not just an emissions device. In hotter climates, going up hills, or if you get gas from a place that doesn't have an accurate octane rating, pinging may be encountered. The EGR helps do deaden the air/fuel mixture, eliminating harmful pinging (knocking) which if left to its own will destroy an engine.

Just in case: Pinging or knocking is when the mixture is prematurely ignited before the piston reaches TDC. Aggressive knocking sounds like a few marbles are bouncing around inside your engine.

[TLdream]

Very nice way to put it paton. From information i have gatherd from other sources, its not a good idea to block it off unless you have some kind of tuneing device to help "tune" it out.

[IDon'tKnow]

The ignition event always takes place well before TDC, it's premature flame propogation that is defined as detonation. (Just nit-picking)

I agree that it should be left in place for the majority of street users. On the other hand, has anyone ever seen a race engine use EGR?

[paton]

The ignition event always takes place well before TDC, it's premature flame propogation that is defined as detonation. (Just nit-picking)

I agree that it should be left in place for the majority of street users. On the other hand, has anyone ever seen a race engine use EGR?

Mmmm, touche sir. Saying "before TDC" was much easier than saying... "Without the EGR, the combustion event may occur even further before TDC than is intended."

...but it was easier to just say TDC...

Still however, I'm sure there will be those who will benefit from our little banter.

I continue to track your build. Still impressed man.