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M42 Swap evap/vapor tank options


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Finishing up an m42 swap and had some questions on my options regarding purge control valve, vapor tank etc.


The car (1976) did not have the in-trunk expansion tank and the tank filler was vented directly out of the trunk when I bought the car, and its been that way ever since.


The m42 did not come with a purge valve.


The way I see it is my options are keep venting straight out and either add a dummy purge valve or resistor to eliminate the CEL. 

Do the same but add a charcoal canister before venting to slightly offset the eco-damage/fuel smell.

Buy a used stock expansion tank, m42 purge valve, run the vent all the way up the car to the TB and hook it up as intended.


Although I am a certified tree-hugger, the last option seems like far too much work and expense for a car that will be driven occasionally at-most. Am I completely misunderstanding how this stuff works? I know a proper operating system should have slightly better mileage since it burns the vapors instead of dumping them, but is it that big of a deal? Can I add the expansion tank and still avoid running another hose to the engine bay and collect and return the vapors in some other manner?




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