Applying presoaks with no dwell time in between. Rather, at the end??

[Officer]

I've seen some operators applying presoaks hi/low or low/hi (not my point here) without a dwell time in between. Rather, the dwell time is at the end once both soaps are applied. I've even seen triple foam applied on top of the presoaks after the dwell time, before high pressure rinse.

Anyone see any advantages or disadvantages here?

 

[carwashireland]

I find that if their is no dwell between lo and hi then you struggle to get the eyebrow off the windshield when low is your first pass. Tri foam over the top is a great way of giving some show on a wash program and gives more dwell to the presoak, as long as it is a ph neutral foam and not a polish. You often see Oasis machines set up this way.