EGR

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Exhaust Gas Recirculation (EGR) was first used starting with 1974 B-210 (North American B210) models. Australia 1200 utes got EGR in 1982. Japan 1200 trucks got it in 1989. It recirculates a small portion of the exhaust back into the combustion chamber. Although this dilutes the the air/fuel mixture (reducing performance), it reduces burning temperatures resulting in drastic reductions of Oxides of Nitrogen (NOx).

Overview

EGR is a key emission control technology. Even the new 2012 models use EGR, although now it can be effected by variable camshaft overlap and engine computer control. Datsuns use an early version of EGR which is heavy-handed regarding performance, but really does clean up the air.

For a detailed explanation of EGR, see the AutoZine Technical School article.

Datsun EGR consists of:

• Exhaust manifold with an EGR port tube
• Intake manifold with EGR passage
• EGR valve and body, which bolts to the intake manifold
• One or two switches

EGR parts in red:

Exhaust Manifold

The only modification to the Exhaust Manifold to enable EGR is the casting is changed to add a threaded port to which a tube is fastened. The tube goes up to the EGR Valve.

A14 FU style

Late A14 style

Variations consist of:

• Size of the EGR port (diameter of hole and thread size)
• Location. Early engine had it come straight out of the manifold outlet, while newer ones have it closer to the Runners