EGR?

[Bruce Plecan]

> David Sagers wrote:
> > What is the purpose of an EGR and why is it used.  I'm trying to decide
if I
> > should connect the EGR for my street hot rod.
> Lots of EGR info in the archives, look there for more.
> Briefly EGR is "neutral" as far as combustion is concerned.  Adding EGR
> doesn't make the air/fuel mix leaner or richer.  It lowers combustion
> temp (not as much fuel to burn) which helps emissions.  It also helps
> fuel economy by reducing fuel at part throttle conditions.
> --steve

OK, less heat.  Less energy to be recovered.  So poorer mileage, and/or
performance?.  Less pumping losses, but that is a theoretical idea.  While
some claim that they can run EGR and get better mileage, I at times wonder.
I hope to do some testing with some of the digitial fully electronic types,
but for the vac., type, I have tested to my satisfaction, that some can open
as a result of exhaust Backpressure at High RPM WOT..
Grumpy