1987 Tank, Walbro 255lph, Question/request

[skyphix]

Hey everyone,
I've never worked with these in tank pumps and am about to order my complete new fuel system.

I had originally planned to use an ep381 pump but decided to upgrade to a 255lph for some room to grow. I am using an 87 tank and sending unit, and all new steel line and AN fittings from hotrodfuelhose.com

I want to make sure I order the right thing; will the 255 pump fit directly in the sending unit or will I need to modify anything? The only photo I could find had a short length of fuel hose running between the pump and sending unit, but looked like it just fit.

Does anyone have a photo of their 255 in a TBI fuel sending unit? Or specific part number/kit to order for the 255 since there are quite a few variations?


Thanks in advance

[jrpontiac]

I used the factory sending unit with an ep381. When I put a turbo on I upgraded to a Walbro 450 and still used the factory sending unit.

[jrpontiac]

I used the factory TBI sending unit with an ep381. When I put a turbo on I upgraded to a Walbro 450 and still used the factory sending unit.

[skyphix]

Originally Posted by jrpontiac

I used the factory TBI sending unit with an ep381. When I put a turbo on I upgraded to a Walbro 450 and still used the factory sending unit.

Thanks! Did you have to do any modifications or anything to get it to fit? It looks like the 450 is shorter with a wider base than the 255. By all accounts the 255 just fits and just works, just having never seen this setup before and my truck under 2+ feet of snow I want to be as prepared as possible with everything needed. Did you have to run fuel line between the pump and the output port? IF so, clamps or no clamps? Part of me says make the line exactly long enough that it will hold itself there so that there's no worry of clamps disintegrating over time, and use FI rated fuel line for that short section.

[jrpontiac]

I had to do some tweaks to it. Forgot exactly what but nothing to much. Used a couple inch section of rubber hose from the pump to sender port. I used FI clamps. I also used a hose clamp around the pump and rod/tube deal that supports the bottom of pump.

[kipps]

Originally Posted by skyphix

...Did you have to run fuel line between the pump and the output port? IF so, clamps or no clamps?...

If I understand you correctly, you're asking about the short hose that's submerged in the tank. It goes from the nipple on the submersible fuel pump to the inside nipple on the fuel sending unit.

You need to use clamps on that. That line is 58 psi, and without clamps, will be leaking fuel back in the tank, and won't be able to build full pressure.

I can't help on fitment of that pump. I'm using ep381, and it fits exactly like the stock pump did in the stock sender(also using that short piece of fuel line).

[Cheyenne350]

I Used the AC Delco 381 with the Dorman gas tank for a 87 R10 and the Dorman sending unit, the only problem that I had was that it would start then die after a few secs and reason was because I didn’t have the in line filter/regulator. Thanks to the response from a few guys on my thread the problem was solved. My post should still be visible..

[Cheyenne350]

http://67-72chevytrucks.com/vboard/a...1&d=1551765861

Dorman sending unit with Ac Delco 381 fuel pimp

[skyphix]

Thanks everyone for chiming in and for the photos - I'll use some FI rated clamps on it then.

The EP381 is what I was originally going to use, but since I'll be testing my turbo engine in my truck next year before it goes in the yet-to-be-purchased race car, I figured I'd do the 255lph now. From the one photo I found, it looks like the 255LPH and the EP381 are physically the same or close enough that the setup is going to look exactly like with the EP381 installed. Keeping the boost low in the truck so didn't want to jump up to the Walbro 430 or one of the Aeromotive in tank pumps just to run a close to stock 5.3 in the long run.


I'm going to run the Corvette fuel filter/regulator mounted as close to the fuel tank as I can on the passenger side frame rail (I have pass side fill.) Ordering all of this in the next week or so as my expense checks come in and am chomping at the bit! First time working with braided line, first time with a saddle tank and GM pump assembly (I've done this work in Subaru's but only once.) Seems pretty straight forward and simple enough. Appreciate the help and advice!

[87chevy.com]

Racetronix has a bracket that i think works with the 450... it's basically a thick tube with a base welded to the bottom and said tube has set screws to clamp onto the stock sending unit... I wound up making a bracket from some 3/8 stainless steel tubing and 2 stainless steel hose clamps for my gen5 l8 swap. Main goal was no rubber in fuel tank for e85!.. e85 will eat up submersible rated high pressure fuel line...
Clint

[skyphix]

Originally Posted by 87chevy.com

Racetronix has a bracket that i think works with the 450... it's basically a thick tube with a base welded to the bottom and said tube has set screws to clamp onto the stock sending unit... I wound up making a bracket from some 3/8 stainless steel tubing and 2 stainless steel hose clamps for my gen5 l8 swap. Main goal was no rubber in fuel tank for e85!.. e85 will eat up submersible rated high pressure fuel line...
Clint

Your builds sound like they're both going to be pretty fun! There's basically zero E85 availability here, so once I get to the race car build I'll switch between a 91 octane E10 map and a 100+ Octane map for race gas, using an external pump and dual filter setup out of a fuel cell.

Thanks for chiming in!