[mwebb]

...."Wrong.

Test this with a vacuum gauge when you manually introduce EGR.

Vacuum drops, which means more mixture in cylinder at BDC on intake stroke, which means more compression at TDC on compression stroke. More in=less vacuum=more compressed=more compression.

Basic physics

The same applies for a vacuum leak introduced by disconnecting any hose from the manifold, except that allows more air into the cylinder instead of more exhaust.

regards
Mech"....

ooops
you forget that the pressure that we are working with is Baro pressure , not intake vacuum , Baro pressure is constant
Baro pressure is what forces air into the combustion chamber when the intake valve opens ,
and the EGR originates in the exhaust , where pressure is slightly above Baro

there fore , the amount / volume of gases in the combustion chamber is NOT changed by the addition of INERT EGR gases
, the INERT EGR gases displace some of the airfuel mixture , the combustion chamber AF ratio is not lean or rich .
it is diluted
with
INERT EGR gases

basic s
now that that is corrected
thank me

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