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I use Lucas upper cyl lubricant. I used to use tektron until I noticed it was removing the plating on my filler neck. I put lucas in a small gas can, and mix it with a couple gallons of fuel. Then I put that in and only about 5 gallons of super. For a new to me car, I usually do that 3-5 times. Seems to make a big difference. I'll put a treatment in about twice a year to keep things clean.
Any well known brand will pretty much work the same, trick is to not use it constantly. Knew someone who thought using it often (like 1-2 times a month) was a good idea. Deteriorated the o-rings on his injectors, ended up with gas leaks all over the top of the engine.