full twins infront of the wheels is fairly easy if its legal on your vehicle, although i dont hugely see the point unless you have a V configured motor so so you have a manifold on each side to start with. Twins behind the diff isnt as easy depending how the exhaust bends over/around your rear axle....

LOL. a Y collector behind the diff somewhere into twin pipes should work ok provided you can get them fairly straight n even. Might not be the best if you were counting and relying on every single horsey, but i doubt it will make much effect on a turbo diesel

Do what the yanks do with thier Chevys n such.. twin stacks out behind the cab although admittedly they are like a 6.6L cummins or duratech t/diesel I must admit i do prefer the uniform look of twin pipes tho. Prehaps 2.5 to the diff then 'Y' into twin 2.25s or something?

yeah shame you cant buy them here, i sold a good MIG as i also couldnt justify renting a cylinder to use it once every now and again. In England you can buy small disposable cylinders much like a sodastream cartridge but about twice the size in various ar/co2 mixes. Tried to find my old reg for them...

Hey guys, Clive from Tauranga.. started getting into 4wd'ing a while ago when i had my bighorn (up until a not so pretty relationship breakup..but we wont go there :twisted: ). Anyways, got some inheritance coming in a couple of months so looking at buying a MU (always liked the shape), along with a...

man im so keen to go up there! wish i had my MU now.. going to be a loooong couple of months wait

i would suspect either an internal blockage as previously mentioned.
or at a stab in the dark if the timing is too far advanced will cause the engine to run warm under higher load (petrol)