Hi its a VR4 they are all galants
just made of more expensive case hardend cheese (oops metal) LOL ggod to drive though, Eurocarparts are now doing repro parts i have an extensive list of parts sourced for less than our freinds at Mitsubishi would charge if you would like it
Got a couple og BGT;s and my Fav is my 1978 260Z 2+2
If the Master was sticking it would effect all the brakes as they are dual circuit ie 2 front and 2 back off a split cylinder, sounds like they are not returning,
A few easy things before you go the long road,
Have you checked the pads to see if they are running off this will indicate if the calipers are not pressing evenly, or twisting
check the bushings on the realease studs, the Alan key ones you loosen to change the pads,to see if the calipers are twisting, by getting a good hold and wiggling them if there is significant movement on the calipers they will twist under load overheat and stick. (major front brake issue on the Galants/ Legnums as well) too much weight on these power units 2.4 deisil hanging out the front
have you given them a really good bleed? ie 1 litre through each corner DOT 4 nice and slow, our 156 suffers terribly with Hydroscopic problems in the fluid i do them twice a year.
Give the calipers a good clean and behind the dust seals (the rubber bit) and a thin coat of copper grease reseal
Like hens teeth in the scrap yard although if you wait till around Octoer there is an influx of V6 cars with front corner damage where the change in the weather catches the heavy footed out LOL you may be lucky.