Originally Posted by CaptOz
Do I have to re-tune the rack if I am just swapping injectors out?
I would say as a minimum you should check the height (Timing) when the injectors are installed.
This is a pretty easy job and there is or there used to be a tool available from DD that is the exact height for your Injectors. If you can't get the tool set a digital vernier to the correct height and use that, it isn't as easy as the proper tool and you have to pay attention that you hold the vernier straight and the setting doesn't get bumped as you go.
Years ago I was on a field job and had to make a tool out of stud bar and a couple of nuts to set 1.484" on a 3 53 as I had mislaid the correct tool, must have got it close because it started straight away and ran well.
To this day that "missing" tool has travelled the world in my toolbox and I have never needed to use it again.