[rfmaster]

Originally Posted by Jim85IROC

Any issues with using the dual-tank setup with a high-pressure late model EFI system? My 87 has a stock tbi 454, and sometimes dirty thoughts of a 6.0 keep creeping in. I've seen my share of guys putting TPI on their trucks, but never noticed if any of those used dual tanks. I understand that I'd have to upgrade the fuel pumps, fuel lines, etc, but wasn't sure if (or how) I could retain the dual tank switch-over business. Can that equipment handle 55+lbs of fuel pressure? If not, what are my options for retaining dual tanks?

A short answer is no, but it can be worked around. The transfer switch is low pressure design - and can only only handle 13 to 20 PSI needed for TBI operation. For TPI or any other port injection system operating at 3-bars (43 PSI) transfer switch will not fare well.
A simple solution is to build a small surge tank between fuel supply transfer switch and new high pressure fuel pump rated for TPI or 6.0 L operation. A purpose of a surge tank is to act as a buffer between TBI in tank pumps and provide uninterrupted fuel source to high pressure TPI pump. In another words OE, in tank TBI pumps act as fuel lift pumps, delivering fuel into surge tank. Excess, overflow fuel from the surge tank is returned back to selected main tank. TPI pump takes fuel from the surge tank, via fuel filter, and return line from TPI rail dumps excess fuel back into surge tank. See attached diagram and a photo of my surge tank:

//RF