The author of "Corvette Fuel Injection & Electronic Engine Management" (ISBN 0-8376-0861-9) writes...

Any thoughts on this? Specifically about losing power and increasing possibility of knock?

 

When the ECU is commanded to turn EGR on in a Speed Density system - it A) Reduces the calculated VE term and B) adds spark advance. MAF should only need spark advance.

EGR in nature (MAF and SD/MAP) will will reduce the throttling losses by a small percent. It requires slightly more throttle angle for the same power. That is where the slight fuel economy difference comes in.

The spark advance is there (MAF or SD), as well, which will bring it closer to knock, but if the knock sensor works, it won't bring any significant trouble to most.

But, if you do your own chips, you can disable it properly, and the economy difference is nil according to those that measure there economy and have disabled their EGR (I disabled it, but drive (drove I should say) in the city mostly, plus mine was malfunctioning).

 

What he said.

Disable it properly thru tuning and go from there.

Just blocking it off or otherwise disabling it wont stop the ecm from running its functions when its active.

later
Jeremy

 

The wording... spoken like someone who has never done it themselves.

 

You will not lose power. Some people report getting knock with no EGR... I have never. If you do a good job of tuning after blocking the EGR you will have no problem anyway.

 

I have EGR, but its not from an EGR valve. The cam overlap in my engine gives me EGR. Same thing, just not controlled at idle like an EGR valve. Anyone ever opened up an EGR valve at idle on an engine (grabbing the underside of the valve and lifting), it runs just like a cammed engine. Big Cam with more than stock Overlap=Internal EGR (LT4 corvette)