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Base pressure w/ twin pumps
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Old 03-28-17, 03:25 AM   #1
SlowInFastOut
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Default Base pressure w/ twin pumps

Hey everyone!
Theres a quite a few of you guys out there running big numbers and also relatively snappy DD setups. I found myself in a pickle fueling wise and so here is the dilemma.
-current set up for fueling is
Aem 320 e85 in tank(stock fpc)>stock rear lines>iag fuel line kit with cobb flex fuel adapted to it(6an)>iag rail(8an)>ID1300cc. Base pressure of 45psi.
The 1300s on e are maxing out at >110% duty and it seems to be static open with the pump just directly dumping fuel. Air thrown by a 1.5xtr at 26.6psi avg (e85+meth). The aem drops volume of flow hard with base pressure increases, so after i saw the new revised radium dual pump hanger with the stock-like canister i thought i would go that route with twin aem 320 50-1200 e85 and run a fuelpro unit for each pump. However the issue arises of how would twin pumps handle added pressure or do i go to id2000s at 3 bar stock pressure. If i dont have to spend the extra on the id2000s it'd be great.
Feedback is much appreciated. I know most of you guys will say big wally with a BAP or twin pumps with a hobbswitch and id2000s. But i like the wierd stuff. 😂😂😂😂 also running 93 occasionally is necessary. Also never thought a dom1.5 would do this either.
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Old 03-28-17, 11:51 PM   #2
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Default Re: Base pressure w/ twin pumps

There's a reason most of us will say big walbro. One pump less to fail than dual pumps and you'll flow plenty to max out your turbo, plus it's pretty simple to hardwire it vs a separate controller and if you want to take a step further you can just keep your current in-tank setup and put a big walbro in a surge tank instead.

You definitely don't need a bap either if you go for a 485. It'll flow way more than your turbo could demand.
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Old 03-29-17, 05:49 AM   #3
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Default Re: Base pressure w/ twin pumps

[QUOTE=8cd03gro;4307834]There's a reason most of us will say big walbro. One pump less to fail than dual pumps and you'll flow plenty to max out your turbo, plus it's pretty simple to hardwire it vs a separate controller and if you want to take a step further you can just keep your current in-tank setup and put a big walbro in a surge tank instead.

Im not all too worried about wiring a controller or anything in that regard. I defjnitely agree that to have a separate surge tank sounds like an awesome idea but as my daily i try to keep the oem locations of parts and units. The less i have to add in, the better. Running ptfe fuel lines everywhere and getting the associated hardware and All the extra expenses turns me off a bit.
With the twin pump idea, i have a fuel pressure sensor already set in place with also a mechanical guage for monitoring. The plumbing is minimal as they make a pre measured kits to install it in the 08+.
Wiring a controller is as simple as hardwiring a fuel pump to do 100% all day long. Switched 12v ignition with 40amp relay to the fuelpro unit, fuel pro unit powers and controls pumps via 5v pwm line from stock controller.
My real concern is what do i assume when i crank the base pressure up to get more at the injector? Do both pumps work equally against the regulator? Does it still maintain it's diminishing flow factor as pressure rises from high base pressure and boost?
I do appreciate and feedback! Thank you! And the big wally is still on the table if it becomes the most reasonable. Will just have to mod the canister or get a hanger for it that has a stock like can to sit in or make one for that matter.
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Old 03-29-17, 01:47 PM   #4
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Default Re: Base pressure w/ twin pumps

I don't mean the wiring of the controller is complex, I mean from an engineering standpoint hardwiring the bigger pump is simpler than two pumps and an external controller.

You're just adding complexity by going that route, unnecessary complexity. That doesn't mean a dual pump setup couldn't be totally fine though.

I'm not so familiar with what kind of hanger modifications are necessary on your year, but I imagine it's similar or less extensive than a dual pump setup. Personally I'd prefer Walbro vs DW or AEM pumps anyway. Add into that you're intrinsically doubling the risk of failure with a dual pump and you're adding in a controller. . . I just don't see a reason for it. A hardwired 485 will reliably meet your needs and then some and it's a common modification that has been proven over and over again.

The reason I like the surge tank setup (outside of the obvious benefits of the surge tank itself) is you can keep a wally 255 or similar in the rear without modifying hanger or wiring, then do all of the custom stuff in the engine bay at the surge tank. No extra wiring or fuel lines going to the main tank, just feed the surge in the engine bay after the firewall and all of the lines and wiring is done there.
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Old 03-29-17, 04:28 PM   #5
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Default Re: Base pressure w/ twin pumps

A single Walbro 450 and an aftermarket FPR (which you should already have at this point) would handle a 1.5XT-R just fine, especially with ID1300's.
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Old 03-30-17, 05:46 AM   #6
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Default Re: Base pressure w/ twin pumps

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Originally Posted by 8cd03gro View Post
I don't mean the wiring of the controller is complex, I mean from an engineering standpoint hardwiring the bigger pump is simpler than two pumps and an external controller.

You're just adding complexity by going that route, unnecessary complexity. That doesn't mean a dual pump setup couldn't be totally fine though.

I'm not so familiar with what kind of hanger modifications are necessary on your year, but I imagine it's similar or less extensive than a dual pump setup. Personally I'd prefer Walbro vs DW or AEM pumps anyway. Add into that you're intrinsically doubling the risk of failure with a dual pump and you're adding in a controller. . . I just don't see a reason for it. A hardwired 485 will reliably meet your needs and then some and it's a common modification that has been proven over and over again.

The reason I like the surge tank setup (outside of the obvious benefits of the surge tank itself) is you can keep a wally 255 or similar in the rear without modifying hanger or wiring, then do all of the custom stuff in the engine bay at the surge tank. No extra wiring or fuel lines going to the main tank, just feed the surge in the engine bay after the firewall and all of the lines and wiring is done there.
Ya i see what you are saying. I also just reread a few other threads that ive been going through and i guess i had it in my mind if i were to ever go surge tank i would replace the stock hardlines and do ptfe an lines from rails to surge tank and surge tank to main tank. At the current build i am i guess feeding a surge up front is definitely an option.
Im definitely going to keep the duty cycles though. I know the wally pumps have the capability of crazy hours of 100% operation but i sleep better at night with duty cycles on it as a daily.
With regards to pump failure of dual pumps i can see where i am taking the risk with drops in fuel pressure under boost if one of them dies. Lean conditions definitely wont serve me any good. This idea was brought to me by my tuner and he seems very confident with it and has done just shy of a couple dozen builds with over 2 years of usage on most of them with no issues. It may be just a marketing thing for them but if he has confidence while on the dyno then i guess i cant complain.
Thank you again for the feed back!
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Old 03-30-17, 06:00 AM   #7
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Default Re: Base pressure w/ twin pumps

Quote:
Originally Posted by yamahaSHO View Post
A single Walbro 450 and an aftermarket FPR (which you should already have at this point) would handle a 1.5XT-R just fine, especially with ID1300's.
Tried to multi quote my phone but wasnt happening.

But yes i do have in use on my build an aeromotive fpr set to 3 bar fuel pressure. A walbro 450 seems to be the go to, but as stated above the tuner has built confidence in the radium dual pump hanger with twin pumps. So i dont exactly want to stray to far from it.
The single aem320lph with id1300ccs i thought would be more than enough on e85 but with retaining the stock fpc, the pump would drop in voltage and i would occasionally be up to the 100%-117% duty cycle on the 1.5XTR to feed fuel. On the wide band as i reach the top end it would lean out from 12.1 or .78 to 12.7-12.8 or past .85 which for me i think is quite lean.
Im gonna give this a try and see how it does with the new radium dual pump with twin aem 320 e85 pumps through fuelpro controller. Thank you as well for your info! Like you guys said, we have all seen the 450 walbro for years hardwired holding up well. So ill try this and compare. I think the 1.5xtr is on it last legs at this point as well. 27.5psi on e85 with a little meth.
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Old 03-30-17, 06:04 AM   #8
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Default Re: Base pressure w/ twin pumps

Dual pumps for a 1.5XT-R seems absurd and simply more complex than it needs to be. It's a 49 lbs/min turbo. I run a 53 lbs/min turbo at 23 PSI with a single hardwired Walbro 450 and ID1300's at a 3 bar base pressure and still have plenty of room to go with fuel usage. Surge tanks are nice to have, but I save that for track cars that are really sloshing fuel around.


If you're using the stock controller, you're not running any pump to its capability. This would be a better option: DCCDPro FUELPro Fuel Pump Controller - RM Autosports
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Last edited by yamahaSHO; 03-30-17 at 06:14 AM.
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Old 03-30-17, 06:16 AM   #9
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Default Re: Base pressure w/ twin pumps

Quote:
Originally Posted by yamahaSHO View Post
Dual pumps for a 1.5XT-R seems absurd and simply more complex than it needs to be. It's a 49 lbs/min turbo. I run a 53 lbs/min turbo at with a single hardwired Walbro 450 and ID1300's at a 3 bar base pressure and still have plenty of room to go with fuel usage.


If you're using the stock controller, you're not running any pump to its capability. This would be a better option: DCCDPro FUELPro Fuel Pump Controller - RM Autosports
I actually had ordered the fuelpro the day i made this thread because i had believed there was no way in hell the 320 aem couldnt support a 1.5xtr with 1300s. Still waiting on the fuelpro unit to come in.
It was funny because a rep had tried to tell me that the 320lph pump would be fine on the stock fpc and support the 1.5 fine. But after the few logs and through a couple consecutive pulls the pump drops off in voltage and i dont get the flow up top so the injectors stay open longer.
I didnt mention that i went dual pumps for future turbo plans after the 1.5 as im not sure its a thing yet until some personal business gets taken care of so i liked having the early stages taken care of.
As far as why was the in tank aem320lph was not hardwired to begin with was per request of tuner and my need to want to keep the duty cycles. I have a dw hardwire kit sittin in the trunk.
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Old 03-30-17, 06:39 AM   #10
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Default Re: Base pressure w/ twin pumps

Even a 255 is not driven to it's capability on the stock controller. Past a VF39 and a 255 pump, I always recommend hardwiring.


I regularly see things like this... People with little experience tell you something minimal will do the trick without doing it right. Then on the other side, people over-build because they're not sure how to do right without doing such a big build.

I've got a surge tank on my S2000 and I love it. For my STi being a street car, I kept the in-tank surge with a single pump. I haven't had fuel starve yet and my drive is curvier than most.
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