I always have Marvel and use it for many things. Using the right oil helps too in some cases.
Hydraulic lifters years ago could be a problem in a performance car. In the mid 60s while still working for a Ford dealer, customers with 390 GTs were having trouble with valve train float. Especially in hot weather. I would cure it by draining out the Rotunda 10 W 30 and put in 30 and sometimes 40 wt. DA oil. They thought I was a magician. Those engines picked up 1000 RPM. From floating between 4K and 4.5 K to 5,000 and 5500. These were new or fairly new factory stock Fords. Dealer was not happy with me using none Ford oil.
That kind of thinking is one reason I opened my own shop in 1967.
I ran into that hydraulic lifter problem many times during the 60s and 70s with many brands of cars. One incident after I opened my own shop was a 3 year old 71 Coronet 426 Hemi. My customer had me check it out as it was running weird. It was very hot weather like now. Acted like a bad cam. I took valve cover off while engine was still hot. I opened a random valve and was going to roughly check real quick the lift on the cylds in question with a machinist rule to see if a lobe had wiped out. When I went to put the 6" rule to the retainer the valve stated moving toward closing.
The damn 71 426 Hemis had hydraulic lifters!!! I had worked on 426 hemis before, but not a 71. I looked in my new Motors Manual at the valve settings---and sure enough for 71 426 hemi the valve adjustment spec read ZERO!
I called my customer and asked what oil was in it. It was a major brand 10 W 30.
I drained the oil, changed the filter to a racing filter and put DA 50 wt. in. That cured the problem.
In later years hydraulic lifters improved. And of course in the after market there are choices of various types of hydraulic lifters. Now we have the problem with oils with less phosphorous additives that created a disaster for flat tappet solid and flat surface hydraulic Lifters. The oil companies decided most modern engines had roller type lifters and backed off those important additives ness. for flat tappet cams. Prob. cheaper to make. But in a short time ---The American Ingenuity and business people saw an opportunity for a new lubrication market and rose to the problem.
Today there are countless brands of additive's and oils to accommodate flat tappet cams. Which I use with all my customers engines as most are flat solids or solid roller. I do a few hydraulic. The roller lifters , solid or hydraulic do not need the additives or the oil with them--the industry claims
But all my engines get that addatve and the oil with it. Even rollers.