I have an RV8 in my Half built sumo. I was advised to fit a silver top facet pump. I think it was £65 or so, you can find them on Ebay. This should delivery 4-6 psi to the engine, but will be a little low on full throttle.
You can fit a red top facet pump that can deliver over 6 psi but you will need a regulator too, as too much pressure will flood the engine. It really depends on the trim of your engine and how your gonna drive the car. If you have a big carb, race cam and drive everywhere with your hair on fire then a red top pump with a regulator will be needed. Standard engine with lesiurely drives through the countryside and a silver top should be ok.
Of course this is only my opinion and no responsibilty can be taken for being wrong
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