there's not really good chart to use, because the data mostly sucks. i had used a nice Brookfield rheometer ($20K) to gather this data, and i was fairly disappointed. here are general conclusions for a few popular oils.
trinity is lightest and linear in steps
assoc and losi are similar and linear in steps
hudy/serpent is generally heavier and exponential in steps
all of the oils tested exibited crappy qc. we had some oils that were out of place in nearly every brand, eg.: 60 > 70.
my advice is to copy the brand on the setup, or if you are doing all your own tuning, get a few bottles of each weight and combine them. that way you will have enough of the same silicone oil for the life of the car.
- jr levitz -
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