So neilly helped with a bit of internet research about turbo outflow pipes and I decided my home made job didn't make the spec required. Purchased new inlet and outflow pipes and fitted them today. The outflow pipe was still wanting to kink. This issue is that I can only tighten the bottom nut of the outflow pipe to block union so much. The 'collar' of the pipe isn't pulled down square and tight, if I do tighten it down fully, when the hose union is pulled square it kinks the pipe. I've taken a picture to show this, but the site isn't loading pictures at the moment. So, I haven't fully tightened that nut. However, it's low pressure oil coming out through that pipe and I reckon the tapered union part of the pipe will still be sealing on the tapered part of the fitting on the block. Even if the nut rattles free the pipe won't pop off the fitting as it was extremely difficult to force the pipe on to the union anyway. If the nut rattles loose the pipe should just sit there and the oil trickle back in to the sump. Anyway, I doubt very much that it will rattle loose.