Allied washoe on 4th st, take the prater/4th st ext from I-80 and head west, they are on the south side of the road next to the railroad.
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$6.50 a gallon but for every 50 gals you buy you get 5 gals free. The first time you buy it ask for Sarah and tell her you want to start a race gas card.
They sell Sunoco 100 GT unleaded, they have a big tank with an electric pump out the back. They are open 7 or 8 am - 5 pm weekdays, and 8-12 saturday. They will fill a container or just put it straight into your car.