QUOTE(Root_Werks @ Jul 1 2022, 05:21 PM)
Others will correct me if I'm mistaken, but I thought a plastic expansion tank was the cutover to single 3mm line from expansion tank to engine bay. The charcoal canister resided there.
no.
(but you are correct that all plastic ex tank cars had one or the other of the engine bay can instal locations).
the cutover point for shifting the can is about 3 weeks into the production of 74 1.8s.
around about the period 16-19 Nov 1973 it goes to the engine bay.
they carried on with metal expansion tanks well into calendar year 1974 for 74 MY.
there was basically two batches of 2.0L cars for 74 model year.
an earlier batch in 73 calendar year that all have frunk cans.
a later batch in 74 calendar year that all have engine bay cans.
in between is a big batch of 1.8s that start around about beginning of nov 73 and run through to approx some time around end of feb 74. know with some certainty that commencement date of 1.8s but more hazy on when it comes to an end and they start building 2.0s again. its a funny old year the 74 MY. the L jets were late getting into production.
the engine bay can instal is way easier than trying to do a frunk install on a late car.
you would have to get those big hoses in down the lhs sill behind the rocker panel.
and probably drill holes in body work etc for a frunk can.
with a bit of luck the original small diam nylon hose from when the car was built might still be in the cabin tunnel for hooking up to. which would make an engine bay can install real easy.