The non-egr intakes are illegal in some states to install on an egr equipped car. Also engines with EGR had Exhaust gas recirc passages in the heads to plumb exhaust gas to the EGR intake port on the manifold. Then the EGR valve would allow some of the exhaust gas back into the intake ports to be burned again as a pollution control. Some engine designs (73-79 pontiac for example) will exhibit a terrible exhaust leak at the intake manifold when a non-egr intake is used on EGR heads. The ports between EGR heads and Non-egr intake manifolds don't line up. When that happens, you've got to run an EGR manifold, or swap to non-EGR heads, or fill the EGR passages in the head with high temp epoxy or molten lead.

good luck

chip

Preaching the Hot Rod Gospel according to the 4-stroke apostles:

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