This was such an inexpensive mod(140 total), I decided to ditch my TREX pump even though it was working fine. I have a boost pressure switch that I bought off ebay that turns on the secondary pump at 4-15 psi and is adjustable. I also have another switch that changes which pump is the primary. I got the Y block and high flow fittings from jegs.

One thing to note about my stock fuel lines. The inlet for the fuel feed line is 5/16 whereas the rest of the line is 3/8. I cut about 2 inches off the inlet so the whole feed line is 3/8 now.

 

What guage wiring are you using for the second pump and where did you order the pump? Thanks!

-B

 

nice work!

 

If you could give us a parts list that would be great.
Which pumps did you use?

 

I bought the flex hose, pump filter, 2 extra long Walbro connectors, 2 5/16 intank hoses, and Walbro Pump from Auto Performance Engineering. The extra long walbro connectors are 14 guage. The wiring outside the tank is 12 guage. Sealed with JB weld. Metripack Connectors (connector at top inside of tank)at Pep Boys. 555-15110 is the jeg's part # for the yblock. 720-2965 is the jeg's part # for the fittings.

 

Cool! Now the boost reference switch turns on the power to the fuel pump via a relay I would assume? Also do you have a schematic of how the switch and or pumps are wired up? Thanks!

 

Correct. The stock fuel pump relay has a reference wire and the aftermarket relay has a reference wire(turned on by boost switch). I placed a switch up under my steering column that switches these two reference wires. Now i can drive the primary on odd days and the secondary on even days. It also allows me to have a backup limp home pump. The stock fuel pump relay is under the steering column too. Check out this boost pressure switch.http://cgi.ebay.com/ebaymotors/Boost...agenameZWDVW:D

I didn't need to hack up my intake manifold to put a hobbs switch in.

 

What exactly do you have to hack up on the intake to run the hobbs switch? Excuse my ignorance.

 

No need to make a hole in the intake manifold for the hobbs switch to screw into to get its boost reading. The switch I bought can be put inline with any 1/8 inch vacuum hose. I spliced it into the vacuum hose that goes to the AIR pump.

 

You are the man....thanks a bunch.

Just as a reference...the part numbers you have are for 3/8 fittings.
If anyone wants to go to 1/2 inch to supply a larger line system these part numbers should get you started.

555-15112 for the y block
555-15977 for the fittings

 

Have you tested this yet and verified it's operation. Not that I'm doubting you, but for the price vs. the cost of one of Lonnies dual in tank pump setups, I may be willing to give this a shot myself as it doesn't look like it's that difficult of an item to put together.

 

I take it the hole is rather large thus the reasoning to go w/ another switch? Guess I'll go the msd activated switch if that's the case. I wonder if Lonnie mentions this in his pnp setup. Doesn't sound pnp to me. Hmm.....

 

I was thinking the same thing..... somone correct me if I'm wrong but I'm assuming Lonnie's set up is -

2 - Walbro pumps
1 - Y block of some sorts, barbed fittings
1 - EFI hoses to connect to the Y-block
1 - Dual pump harness, relays, inline fuses, electrical connectors for the fuel pumps
1 - Hobbs switch
Various conectors to alternator and ground.

From the looks of it I can't see how its going to cost $600?

Does anyone here have Lonnie's setup and can comment? His set up requires you to send in the stock bucket so it makes me wonder if he keeps one pump in the bucket and one outside.

-B

 

Exactly. Which is why I'm inclined to go with this on my own as it can't be that difficult to install and wire in.

Another thought though: The LT1 uses the return feed into a pump bucket to ensure the pumps always have fuel. What are the odds of a custom bucket fitting through the opening??? Just a simple aluminum (or stainless or whatever) very closely sized around the two pumps??? Doable?

 

Before this rebuild I was running without the bucket for 4 years no problem... however once I drop the tank again I might just leave one pump in the bucket and one on the outside however Im not sure if there are any drawbacks to that set up.

From what I read if you try to wedge 2 pumps in the stock bucket... both of those pumps are gonna suck any fuel you have in the bucket completely dry anyways.

-B