The powerhead is a J235 1982. Remanufactured in mid-90s - this is a apparently a total, proessional factory type reman because the engine is labeled with the company that did it (no longer in business, can't call). I bought it used about 3 years ago. When I bought it, the guy said "always burn premium", so I have been. Of course, I've been reading all along that one should burn 87 octane or whatever the manufacturer calls for.So, I get an OEM owner's manual (booklet - not the service manual). Fuel specified is 88 Octane, "not unleaded", "not gasohol".Obviously, the wording in this old manual is dated, but I'm wondering about the octane spec. The pumps around here have, I think (from memory), 87, 89 and 90.Can I ASSUME that the remanufacturing process modified the engine so that it can burn 87 safely? Should I just be safe and burn 89? Is there some timing or other spec that would need to be checked to determine if I can burn 87?Is this nothing more than an angels dancing on the head of a pin question?Thanks guys for indulging my obsession.