1 The car has never been snow foamed before - how long do I leave it on the car to dwell before rinshing off? Do you just leave it to dwell or do you have a aggitate it?
As long as it needs it. I go for longer in colder/winter climes and shorter duration in summer. Do not let it dry on. Doesn't need to be agitated but some people use a washmitt and agitate the whole car and rinse. I prefer to snowfoam and then use a raceglaze-style brush to clean all the lines and creases, badges, grilles etc. These are areas where dirt tends to get trapped. Once I've been round the whole car, I then power rinse and move on to 2BM wash. This rinse is where most of the dirt gets lifted and is for me the longest part of washing the car. Thoroughly rinsing means less contamination.
2 How long do you leave the iron x on the wheels for? If left too long does it cause any lasting damage?
I'm sure it tells you on the bottle but generally 5 mins max. As with all products, can cause damage if left to dry on.
Any other advice on using either of these 2 products would be appreciated as I haven't used either before.
I would test out the foam lance settings and mixture settings first. Play around with the lance until you get a foam thickness that works for you. You only need about an inch of snowfoam in the bottle. I top up with hot water as I find it helps the snowfoam to cling better.
Iron-x is fairly straightforward.