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Suggested octane for 80's small block motors?

Skivo

Tuned and Synch'ed
Joined
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Hi all, I have a 1980 V50ii with abnormal combustion. The service manual states 100 octane, which I have gathered is based on research octane (RON). By my calculation this is approximately 95 octane based on the AKI (R+M)/2 used here in the States. Currently I'm using "clean" supreme 93 octane (AKI) and adding octane booster to achieve roughly 95 octane.

Is this the approximate octane I should be using in this motor? I'd love to hear success stories or issues experienced with fuel in similar motors. Thanks!
 
I've found no need for more than the 93, in fact if you have real gas w/no ethanol at 89 or 90 it'll be fine.

Thanks for that info Steve. I do have "no ethanol" supreme 93 around the corner from my house. I use it exclusively when I'm not traveling.
The 100 proof fuel I started out with proved to be too much for this V50 motor and wouldn't combust properly. I've dropped it to 93+octane booster. I'll try straight 93 and see how she runs...

What year/model is your bike?
 
Back in 85 I had a V50III, I road it a couple thousand mi and sold it. Traded my Fiat spider Sport for it, back to the previous owner of it. He wanted my SP 1000 so I got a nice Fiat he worked on. The V50III was his wife's and she quit, riding almost new too. I already had a 84 LMIII and 70 Ducati Desmo 350.
 
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