aquablueg60

Well.... in my understanding a map sensor gives a voltage output dependant upon pressure..... but a 2 bar map is going to reference say 0v at 0bar, 5v at 1 bar. A 3 bar will have 0v at 0bar, 5v at 3 bar....... So the eprom will have to be programmed to reference the correct value Just soldering in a 2.5 or 3 bar map would require an eprom written for that map sensor. Or have i got this all wrong? To be honest i'm only speaking from my experience with standalone systems such as Efi Technology, emerald and Motec.

I have a fairly small AC/DC tig welder. You wont have much luck trying to Mig weld a displacer. The choice of wire for a mig is very limited and all mig welders that i know of work on a DC only current. You need to be able to use an AC current for welding most aluminium and magnesium alloys as the change in polarity of the welding current has a cleaning action which prevents the weld pool oxidising and scavenges the impurities. When tig welding the magnesium you need to use a "like" filler material. I did have a quick go adding an aluminium based filler and although it looked as though it took ok it was easy broken away again with a pair of pliers!

Yes, its a magnesium alloy so its not quite as combustable as the little bits of magnesium you used to burn in science class but it will still burn all the same. The whole point of using a gas when mig or tig welding is to provide an inert shield around the weld pool to prevent the metal from oxidising. Welding magnesium is no different to any other metal really. If you weld steel or ally without a shield gas it will turn to a pile of c*ap. Hence, as long as you have the correct gas shield, the correct flow rate and adaquate pre and post gas flow to create a complete shield there are no issues with welding it.

Got a couple of different gases, argon and an argon helium mix. Not decided which is best yet

Well.... you can use a simple bit of maths to work out what difference is made by the extra head gasket! Good old pi r squared x height gives you the volume of a cylinder. Hence you can work out the volume you need to remove. You are very limited as to what you can remove from the combustion chamber becuse of where the valves seat. There is a little you can remove from around the sides but not enough to drop the compression ratio to a acceptable level.

Hi there, I have just been having a play with a very wrecked G60 displacer, my tig welder and some rather special rods....... Was just wondering if anyone else has had any experience welding them? Does anyone have any spare displacers which are just missing bits of the apex seal groove which they would like to give/sell to me for little money for experimentation purposes :D P.M me if you have :) Any comments appreciated.... even the long stream of ones which are gonna tell me it can't be done....you'll warp the displacer.... you'll effect the heat treatment of the scroll....etc etc etc. Cheers