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1G Bosch 044 install?

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SasaniFab

Proven Member
2,433
782
Dec 1, 2013
Mexico, Connecticut
While im saving for my ppg dogbox i figured Id add an inline pump as im close to maxing out my fuel system. I am currently running a walbro 450 rewired with 6an lines front to back. The injectors are fic high z 1650s. At 36 psi im almost at 100% duty cycle on e85. My question is with the inline pump do I basically cut the line downstream and splice in the pump inline? Then I would need to run a separate relay to the pump? Could I technically have the pump turn on when the ignition is on or should it be spliced in to the factory system so that it turns on when the cas is spinning?
 
I would do 1/2" line or -8AN from tank to the 044 since that's free floating. The 044 intake side is huge anyway.
5/16" line has been proven 500-550 all day long.
The 3/8" line or -6AN you currently should be sufficient for some SERIOUS jam.

Make sure the ENTIRE FEED IS -6AN. If you have one 90° fitting that's 5/16" or one 5/16" adapter you had to use to get your system to bolt together. Sorry, but that's a restriction and you're no longer flowing -6AN... That's something a LOT of people seem to forget/overlook.

You CAN use one relay for both pumps.
The relay just has to be rated for the sum of both at continuous duty.
It goes without saying if running off one relay, the power feed to the relay has to be properly sized / sufficient for the amount of amps being pulled.


EDIT: one thing to note. On 2g's, I would consider it simpler (and better) to wire up, plumb, and run TWO Walbros PARALLEL, in tank, than wiring up and plumbing an inline setup. I am pretty well versed on the 044 and it's capabilities and it does not beat two 255's..

That 450 (not very familiar with it, sorry) should be churning out every bit of what the 044 has to offer so I don't really see any gain putting an 044 inline...
 
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Yeah man you are way over thinking it!

Just make sure to run a sufficient power wire if using the same relay- or I'd use the same signal wire to a seperate relay as to make sure the pumps come on at the same time. I wouldnt want my in tank pump pushing through a stagnant pump or my down stream pump trying to pull through a non moving one.
 
Would it be feasible to run a splitter off the tank running one line to the Bosch to another splitter on the filter? So id be running two lines off the tank to the filter, one would run into the inline and one would continue to the filter? Or is this stupid? What I had planned was to find an area to mount the pump underneath, then pull out the feed line to fit the hose ends on. I could then reinstall the line and connect the pump inline. I would then run a separate relay with a separate + and ground but splice the trigger wire from the stock wiring to trigger the pump to turn on together.
 
While im saving for my ppg dogbox i figured Id add an inline pump as im close to maxing out my fuel system. I am currently running a walbro 450 rewired with 6an lines front to back. The injectors are fic high z 1650s. At 36 psi im almost at 100% duty cycle on e85. My question is with the inline pump do I basically cut the line downstream and splice in the pump inline? Then I would need to run a separate relay to the pump? Could I technically have the pump turn on when the ignition is on or should it be spliced in to the factory system so that it turns on when the cas is spinning?
You really need more fuel? I'm not being rude or facetious, don't take it the wrong way. That 450( I own and use one 6 feed, stock return). Now i have a beast of a car that i totally lost interest in and for all i know i'll need another pump at the likely 60lbs/min the Black will flow on my setup. I must say i doubt that though> That 450 flowed an honest to god, perfectly calibrated 53lbs/min on my fwd m/t pte 5558.
I remember buying injectors, then wanting bigger, then finally just getting my FIC 2150s LOL, i have zero room to talk. if you want to future proof it, I think inline pumps are great.
One failsafe i would add: Don't run both pumps off the same relay. I know, i'm paranoid, but just grab an extra relay.
Good luck man. Sounds like a very fast car you have!
 
Yeah man you are way over thinking it!

Just make sure to run a sufficient power wire if using the same relay- or I'd use the same signal wire to a seperate relay as to make sure the pumps come on at the same time. I wouldnt want my in tank pump pushing through a stagnant pump or my down stream pump trying to pull through a non moving one.
Agreed.Plus, it's a $10, 15 minutes of elbow grease failsafe mode. If they're both being driven off one large relay and it goes kapoot mid pull? Nahhh. Just run the contact VDC to both relays, that's fine, but run your outgoing wire to each pump individually from each relay. And yes, i'm aware that it's a one in 10,000 chance but a little extra safety? For so cheap and such easy work? I'd personally do it. You could easily toast several grand and hundreds of hours of labor if you went completely bone dry lean mid pull. Things would melt rather quickly haha. That's just my novice opinion, so take w a grain of salt bro
 
Agreed.Plus, it's a $10, 15 minutes of elbow grease failsafe mode. If they're both being driven off one large relay and it goes kapoot mid pull? Nahhh. Just run the contact VDC to both relays, that's fine, but run your outgoing wire to each pump individually from each relay. And yes, i'm aware that it's a one in 10,000 chance but a little extra safety? For so cheap and such easy work? I'd personally do it. You could easily toast several grand and hundreds of hours of labor if you went completely bone dry lean mid pull. Things would melt rather quickly haha. That's just my novice opinion, so take w a grain of salt bro
Are you running e85? Close to 40psi my duty cycle is close to 100% , this could very well be tuning related but from what I've read. I am also running a pte 6266, much more air than the Fp black. I am upgrading my feed to 8an to the rail. We will see
 
Oh my, Yes sir, a pte 6266 is a dream turbo. Way bigger than a black. I'm simply putting it in tangible numbers: lb/min airflow. No, a 6266 is ready for some 2150s and, it's been SO long since i was truly into the dsm game, but i wanna say the 6266 could easily hit 75+lb/min. You sir, have a demon of a car. So yes, i see your concern now and i agree with you. I was an idiot and ended spending around 30k for a car that could've easily been done for under 15k. Because i didn't buy big first. I slowly upgraded. Dumb. But, lesson learned and it's not a terribly large sum of money. It's all good

Yes. e85
 
Im running a walbro 400 intank to an inline bosch044. You can splice it in anywhere after the intank. Im running 8an from tank(with bulkhead) to 044. Then 6an to rail. I chose to use one fuse and relay (50amp rated for both) to power the pumps. That way if one goes bad and pops a fuse/relay goes bad both pumps shutoff and i dont go lean without knowing. Also the bosch044 is pretty loud.
 
The fuel pump doesn't care how many lb/min your turbo flows. It cares about boost pressure, since that's what your regular is responding to when it rises 1:1 with boost.

Base fuel pressure + boost pressure (assuming you're using a 1:1 rising regulator, and you should be) = working fuel system pressure. If your pump(s) can't support adequate flow at that working pressure, you'll see your IDCs spike, indicating your fuel system is no longer cutting it for your given setup. Notice I said flow, and not pressure. Just because your pumps maintain pressure at max boost, that does not necessarily mean they are flowing the required amount of fuel.

Running 2 fuel pumps in series combats the issue of maintaining flow under higher pressures. As pressure increases, pump flow decreases. Running 2 pumps in series mathematically does not increase flow under pressure. However, I've seen multiple people using dual pumps plumbed in parallel which did significantly increase flow, so real world the practice does seem to work on some setups.

When plumbing 2 pumps in series, the difference in flow between the lift pump (the one in the tank) and the external pump should be within approximately 10-20% of each other. Any more than that, and you risk starving the external pump. The way to get around this is to add a surge tank between the lift and external pumps, so that the lift pump is operating under little to no pressure.

There's a shit ton of data on this exact topic and more in my build thread: http://www.dsmtuners.com/threads/gstwithpsis-galant-vr4-1837-2000.482807/page-10#post-153619672

Plumbing (size of the lines) is also important, and I think is adequately covered/explained in Bleakley's post.
 
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Would it be feasible to run a splitter off the tank running one line to the Bosch to another splitter on the filter? So id be running two lines off the tank to the filter, one would run into the inline and one would continue to the filter? Or is this stupid? What I had planned was to find an area to mount the pump underneath, then pull out the feed line to fit the hose ends on. I could then reinstall the line and connect the pump inline.
Answering the question about using the 450 to feed the 044 AND the rail is a tough one because I don't know / don't have experience. One thing that DOES stand out immediately is you're probably going to need a check valve on the 450's feed AFTER the tee/Y to the 044. Otherwise that 044 is gonna backfeed (fluid under pressure is going to want to take path of least resistance...).

Hope that made sense. I can do a quick sketch to help illustrate.

In my opinion though I think that's a little more complicated than what you're after (which is just more fuel). I'm a huge advocate of parallel setups.

I see you having two options at your level..
Surge tank setup, three pumps total (which I think is overkill, but will DEF give you a LOT of room to grow, and future options...
OR
You already have one Walbro, grab another. I always recommend keeping them the same. But, contrary to popular belief, you CAN mix and match pumps. All you're after is flow at a given pressure. No need to overcomplicate it. Keep it simple. Whatever you can fit in that tank is what I would put in there. Two or three 255's - Boom, done. Two 450's - Boom done.

I wish I had experience with a 1G's gas tank so I had an idea of what fits in there. 2g gas tank is too short to fit an 044 in there in a way that I would consider 'correctly.'
 
Thanks for your input guys, parts are on the way. I only run ptfe aeroquip lines for ethanol. I decided with 8an feed, I'm going to keep the 6an return for now.
 
The fuel pump doesn't care how many lb/min your turbo flows. It cares about boost pressure, since that's what your regular is responding to when it rises 1:1 with boost.

Base fuel pressure + boost pressure (assuming you're using a 1:1 rising regulator, and you should be) = working fuel system pressure. If your pump(s) can't support adequate flow at that working pressure, you'll see your IDCs spike, indicating your fuel system is no longer cutting it for your given setup. Notice I said flow, and not pressure. Just because your pumps maintain pressure at max boost, that does not necessarily mean they are flowing the required amount of fuel.

Running 2 fuel pumps in series combats the issue of maintaining flow under higher pressures. As pressure increases, pump flow decreases. Running 2 pumps in series mathematically does not increase flow under pressure. However, I've seen multiple people using dual pumps plumbed in parallel which did significantly increase flow, so real world the practice does seem to work on some setups.

When plumbing 2 pumps in series, the difference in flow between the lift pump (the one in the tank) and the external pump should be within approximately 10-20% of each other. Any more than that, and you risk starving the external pump. The way to get around this is to add a surge tank between the lift and external pumps, so that the lift pump is operating under little to no pressure.

There's a sh** ton of data on this exact topic and more in my build thread: http://www.dsmtuners.com/threads/gstwithpsis-galant-vr4-1837-2000.482807/page-10#post-153619672

Plumbing (size of the lines) is also important, and I think is adequately covered/explained in Bleakley's post.
How does this look?
 
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Can someone explain how this could be installed? Would I run a line from the fuel tank to one of the inputs on the top of the tank. That would leave 3 more ports? what do you use these for
 
I've decided to go with a surge tank with dual o44s to the rail. Parts will be here mid week. I'll keep everyone posted... those interested anyway ;)
Been down this road in a similar way.
Since you're about to move serious fuel for serious power...
Triple check ALL fittings for proper internal sizing. I use a drill bit. One that has JUST enough clearance to slide. If one of the fittings or adapters has a step, time to get rid of it..

GST supplied a fantastic diagram - same ones I've recommended.
 
Parts are in guys, I'm going to start the build process tmrw. Plan is to run 6an from the tank to the surge tank as the feed and return. The dual o44s will be 10an to the rail. I'm going to run a high quality low gauge wire from the battery to a fuse box and run wires to feed both pumps. Then run the trigger wire from the stock pump to turn them on. I chose to run all steel ptfe fittings and lines as I feel they are the best for etoh based fuels imo
 
I would run 8AN from the tank to the surge. The Walbro in free float is gonna be moving a sh*tton of fuel..

Also, to help with mounting the Bosch pumps, you can make some lines so the mount next to the surge tank (similar to a radium setup) instead of using those fittings. I think that takes up a lot of space like that AND it seems very rigid..

Your electrical seems on point. One Bosch 044 is good for ~550-700whp depending on pressures and voltages, so -10AN to the rail seems perfect. (More like GOD DAMN!)

Def take pictures man!
 
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