I was wondering what octane do u guys recommend for my 98 225 efi.I currently run 89 with 1 oz. of Stabil Eth. treatment per 5 gallons of gas.Can I run on 87?My motor has been rebuilt twice with 3 cylinders 40 over and 3 20 over,but it should be stock compression on all pistons.So will 87 work or should I stick with 89?
I've been running 87 in my 99 225 EFI and it runs great. I often wonder the same thing, but the price per gallon usually decides for me.
A COMPRESSION test is the best means of answering your question.
IF your compression is within the factory specifications- 87 octane should be fine.
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