The original builder/owners of this car took an interesting, but less preferable approach for the twin tank fuel system.
Each tank has a dedicated pump, filter, regulator and gauge feeding one bank of cylinders. This means both pumps need to operate full time. See attached system diagram.
Additionally, each QFT regulator has one output port connected to tank return with what appears to be a restrictor of some kind. I assume this was done to prevent the Carter P4070 pumps from deadheading at the regulators, but I think the net result will be to lose pressure at the carbs when under heavy load. To test my theory, I disconnected the LH drain at the regulator and capped it off. When I ran the pump, the gauge ran up to 5.5 PSI, rather than 3 PSI as previously set. This tells me that at least 2.5 PSI is bleeding off at static load.
So my plan now is to place a one way check valve in each pressure line (probably where the gauges are located), connect the two capped off fuel bars (dashed line in diagram with one gauge in the middle) to complete the pressure path, and cap off both drain lines. Anyone see a reason why this wouldn't resolve the problem and allow me to run from either tank?
Each tank has a dedicated pump, filter, regulator and gauge feeding one bank of cylinders. This means both pumps need to operate full time. See attached system diagram.
Additionally, each QFT regulator has one output port connected to tank return with what appears to be a restrictor of some kind. I assume this was done to prevent the Carter P4070 pumps from deadheading at the regulators, but I think the net result will be to lose pressure at the carbs when under heavy load. To test my theory, I disconnected the LH drain at the regulator and capped it off. When I ran the pump, the gauge ran up to 5.5 PSI, rather than 3 PSI as previously set. This tells me that at least 2.5 PSI is bleeding off at static load.
So my plan now is to place a one way check valve in each pressure line (probably where the gauges are located), connect the two capped off fuel bars (dashed line in diagram with one gauge in the middle) to complete the pressure path, and cap off both drain lines. Anyone see a reason why this wouldn't resolve the problem and allow me to run from either tank?