Twin pump early car. What cheap pump to you switch to for the external pump??

[nickmcc92]

Yeah TRE-340 255. My bad.

[usualdeviant]

That's cool. I'm excited I finally discovered, for myself, the way to properly update my fuel pump system in my stupid dual pump car. It hasn't been necessary until now. See, first my in-tank went bad which burned out my inline. So I replaced both, with aftermarket pumps. It just so happens the in-tank is an Airtex. Pretty sure that Airtex caused my Import Direct inline to fail five times now. It's time to update that noise.

[usualdeviant]

Haven't had much luck searching, does anyone have any hints on installing this pump? I think I read the word fabrication somewhere. I already have a bit of 3/8" submersible fuel hose coming...

[usualdeviant]

OK so really the only fabrication I had to do was in the wiring. I wanted to unsolder the positive wire from its connector at the top of the fuel pump hanger, then solder the positive wire from the pump in its place, but my allergies were killing me and I was drinking beer so I forgot and I just joined them in the middle with a butt connector. Hopefully the plastic around that connection will hold up alright in gasoline. Same thing with the negative wire, which I used a ring terminal for. Just have to make that 3/8" 30r10 hose about as short as possible to let it all fit in the tank. The new pump is slightly longer than the old.

Oh and it works like a charm!

[usualdeviant]

Been driving my E30 to work off and on since Saturday, and she starts right up the first time, every time! Seems to run a bit smoother as well. I love this forum.

[dougie30]

Just found this: http://treperformance.com/i-6323870-...1984-2007.html Looks good?

BUMP

just wanted to know if I could use this pump and leave my external pump alone..

or is this one designed to eliminate the external pump and just run single intank pump?

[dougie30]

bump will this pump work in sync with my in line pump?? can I just install this without modification?

[usualdeviant]

This pump eliminates the need for both original pumps. All I needed to get things going was the 3/8" submersible fuel hose (a very small length is all you need but they sell it by the foot), and a brass splicer that enabled me to go from the big hose that went into the inline pump to a small hose that goes into the filter. Hose clamps, too, of course.

[usualdeviant]

I guess I could have cut a bit of the metal tube off and put a longer section of submersible hose on, and raised the pump off the tank floor a bit too, but I didn't think of that because I was sneezing with asthma the whole time. Next time I'm in there though...

[willfill]

I just put an in-tank TRE-340 into my dual pump '87 is, it requires some custom work though. The bracket that holds the fuel pump in the tank is too small for the new pump, so you have to cut the brass line that the fuel is fed through. Also, the bracket no longer can hold the pump in place, so if you don't want it hanging from a hose clamp, you need to get some metal zip ties to secure it. I used two, hose clamps are too big to fit the pump in the hole in the tank. Then you have to get some hose barbs, and some different sizes of fuel hose, and replace the external pump with a section of hose, and then use a couple right angle fittings and couplers to route the hose around and down to the fuel filter. I just started it the other day and it ran well, and I am running a 15 amp fuse at the moment. It is recommended to run a larger wire from the front of your car, through the firewall, and to the new pump, and solder it on to the old connector to attach it to the fuel pump, so I am going to do that this weekend as I don't want to drive it for too long on wiring that is weak. If you have any questions you can ask me, I got most of my advice from FLG, so props to him for helping me out so much.

[usualdeviant]

You don't need any right angle fittings if you just curve the hose. The larger wire thing - I would think wouldn't be necessary unless the fuel pump wires get hot while it's running. So since you said something, I'm definitely going to feel them next time I'm in there! Metal zip ties? Having a hard time picturing what size hose clamp you are talking about. Seems to me all you need for the pump itself are 2 hose clamps big enough for 3/8" fuel hose, and they have no issues whatsoever going in the tank.

[dougie30]

thanks for clearing that up for me. also for the wiring, why would it have to be larger? does it need more power thank the original one? and where is the wire that needs to be upgraded?

[lcoleman]

I think the factory wiring is adequate.

That said, replacing it with larger-gauge wire would definitely show benefits. At the higher current that an upgraded pump will demand, the small wire has too much resistance, leading to both a voltage drop (potentially lowering fuel pressure if the pump can't keep up) and lots of heat in the wire. Hopefully the fuse would pop first, but...potentially dangerous. Once again, I think there's enough safety margin in good factory wiring for pretty much any pump you're going to want to use.

You could also run a Walbro as an externail pump and leave the stock in-tank arrangement. The mounting of it will be up to you, I think they're larger in diameter (bummer, the superior Bosch 044 drops right in ;) ).

Personally, I would keep the factory arrangement for simplicity, and use a quality Bosch or equivalent fuel pump. I know that tons of people use the Walbros, but I also hear quite a bit about them burning up, or having a short lifespan. I wouldn't want or recommend one.

[usualdeviant]

Makes me wonder if that short lifespan might have something to do with the factory wiring. Bottom line is, dual pump design was never the brightest! I wish I got an '89 or something!

[dougie30]

I think the factory wiring is adequate.

That said, replacing it with larger-gauge wire would definitely show benefits. At the higher current that an upgraded pump will demand, the small wire has too much resistance, leading to both a voltage drop (potentially lowering fuel pressure if the pump can't keep up) and lots of heat in the wire. Hopefully the fuse would pop first, but...potentially dangerous. Once again, I think there's enough safety margin in good factory wiring for pretty much any pump you're going to want to use.

You could also run a Walbro as an externail pump and leave the stock in-tank arrangement. The mounting of it will be up to you, I think they're larger in diameter (bummer, the superior Bosch 044 drops right in ;) ).

Personally, I would keep the factory arrangement for simplicity, and use a quality Bosch or equivalent fuel pump. I know that tons of people use the Walbros, but I also hear quite a bit about them burning up, or having a short lifespan. I wouldn't want or recommend one.

http://www.ebay.com/itm/Genuine-Bosch-044-Fuel-pump-300LPH-New-in-box-inline-Fuel-pump-With-Warranty-/331156296644

thiss bosh 044 fuel pump?