I would try the four seals on the intakes as a cheap temporary fix. Most of the time the intake guides are fine, It's the shorter, hotter running exhaust guides that will likely need replacing, but they aren't the source of smoke on deceleration.

Some seals for a Datsun 1200 can be got cheap, probably not much more that a buck each. Pretty sure L20B fit too.


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Three 164's, Two 144's, One 142 & a partridge in a pear tree.