Upgrading to run E85 with a frame mount electric pump. As such need to weld a sump kit which will require cleaning stock tank or buying a new tank. I realize the stock tank is 17 gallons but several are advertised as 20 gallon tanks. Sure would be nice to have the extra 3 gallons considering I’ll be using gas at a much faster rate. The first one from tanks Inc. is advertised as 20 gallons but I just called and they said it is identical to the stock tank so must be 17 gallons. Second one I found on eBay the same story. Are there any tanks that have larger capacity or is it safe to say all tanks will be 17 gallons?

Thanks Joe. You maybe have answered my question inadvertently. Perhaps some show imperial and some show U.S. although I don’t know why imperial would be used on an American car. One of the ‘oem’ tanks I saw said 64 Litres, which converts to 17 U.S. gallons.