Guessing Its Head Off Time

[Richie-Van-GTi 74 2 Cars]

If anyones seen my thread in aftermarket wiring they will know my engines very much trial and error and un mapped. Anyway been having issues with it making a popping noise, kind of a random internal type noise that resonates out of exhaust. I was hoping it was down to fueling but its not. So I done a compression test, this is after less than 2 minutes running so engine pretty much cold, WOT and reading O/S to N/S

150/122/145/151 also noted after these couple of minutes running the coolant looked frothy and level ad risen slightly , Im now assuming that pot 3 is blowing out slightly to the coolant chamber

 

So heres why its in upgrades section and not technical. Its currently using 2 x 1.4mm head gaskets as the pistons fouled the head slightly on one gasket (not run, just carefully torquing head). Ideally I need a 2mm head gasket. Does anyone know of one that will fit? I know many XUD gaskets come in various thicknesses but unsure if they are the correct bore and the waterways line up etc. My engine spec is in my sig. I ideally want the pistons machined flush to block but just cannot afford it, unless someone wants to do it cheap/free