RE: OPS .67 nitro marine engines help
O'Donnell-boat-fuel is 17% all synthetic ... I'm not fond of pure synthetics .. ,
I prefer 2 > 3% Castor as a 'safe-guard' , that didn't hurt my engines in 50 years.
On your side of the pond .. buy [link=http://www.klotzlube.com/proddetail.asp?prod=BC%2D175%5FPint&cat=8]Klotz-BeNol[/link] and add 2%.