what oil do you people recommend for 7.5L engines?

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I HAVE A 1989 30' DONZI BLACKWIDOW AND I HAVE BEEN USING VALVOLINE 20W50 RACING OIL.
IM JUST WONDERING IF YOU PEOPLE WOULD RECOMMEND ANY OTHER BRANDS? OR DO YOU THINK THE VALVOLINE OIL IS OK?

YOUR FRIEND IN BOATING

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[Stix Magill]

I am unqualified to give an educated answer, but your oil is probably as good as any. Just change it often.
I bought my Donzi with Mobile One Synthetic and will change it every 50 hours. Supposedly, the synthetic oil runs cooler and can dilute water better than fossil blood. New Corvettes come with Mobile One and no longer require an oil cooler (according to my friend who has two).
You will get a lot of different opinions on this!

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EXTREME MEASURESTHANKS FOR THE REPLY STIX.IM SURE THERE WILL BE ALOT OF DIFFERENT OILS RECOMMEND BY OUR BOATING BUDDYS.I USED THE VALVOLINE LAST YEAR IT WORKED GREAT.THE ONLY REASON I ASKED IS BECAUSE THE PLACE I GET MY OIL FROM SAID THEY WERE ON A COURSE A WEEK AGO AND THEY WERE TOLD NOT TO PUT CAR OR TRUCK OIL IN A BOAT.THE GUY SAID THEY WERE TOLD TO SELL ENGINE OIL FOR STERNDRIVES.


YOUR FRIEND IN BOATING

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[Stix Magill]

There is another thread including plug preference ongoing. Lots of opinions there!

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THANKS SCOTT I JUST READ THAT ONE ALSO
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