If sized right, you can leave the in-tank pump where it is, and add an external pump in-series. Mods would be to cut external fuel line, add fittings, mount and wire ext pump.
boost-a-pump or double fuel pumps?
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If sized right, you can leave the in-tank pump where it is, and add an external pump in-series. Mods would be to cut external fuel line, add fittings, mount and wire ext pump.
HelloBozos
A Bozo in Buick
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Good thread, I run Hotwired SP R1 single intank with volt booster with 72pph injectors at 60psi WOT on stroked 109,GT-71 turbo on 93/Alky with F.A.S.T. ECU. Have had no issues,i DO hate at night when you floor the gas peddle an the Headlights get Super Bright!! One good reason to go duel intank or intake an external an losing the Volt-Booster. I've heard duals are needed to support over 800hp,Singles are fine under that..Watch out if go external,some pumps are Extremely loud!.(BZZZZZZZZZZ) I believe there's kits to go from 12 volt to 16 volt total systems too, better for over all Ignition an accessories as well....
Enjoy!
Enjoy!
Can you adjust the volts going to the pump with the boost-a-pump or is it always all out? Is there any ill affects with going with the boost-a-pump with any of the electronics in the car? Up to 800 hp is good with a single thats with pump gas and alky, but with E85 you need more fuel so the hp will be much lower for the single. I don't know any dual in tank pumps thats is E85 friendly and the DW pump is with a 3 year warranty.
I think I may be leaning to go with the boost-a-pump only because I can't find dual pumps E85 friendly. I guess the hundred dollar question is what will have the most flow l/ph with E85, the DW300 with the boost-a-pump or dual 255's with stock lines?
Thanks, Otes.
I think I may be leaning to go with the boost-a-pump only because I can't find dual pumps E85 friendly. I guess the hundred dollar question is what will have the most flow l/ph with E85, the DW300 with the boost-a-pump or dual 255's with stock lines?
Thanks, Otes.
Pronto
No amount of evidence will ever persuade an idiot.
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Kenne Bell Boost-A-Pump Google is your friend.
Fuel Pumps
We used to run an "inline" pump as a second pump years ago. It was very common in those days before the newer higher capacity "Intank" pumps became available.
There are always going to be some issues when you start to add complications. The K.I.S.S. principal might be more applicable to cars like ours that are already more complex than normally aspirated toys.
Some things to consider is what would occur if one of the two pumps were to become degraded even slightly? What effect would that have on the system? Would there be a difference depending on which pump? How would the flow rate at pressure be compared in order to select the proper match? What would happen if one of the pumps failed?
The rest of the system should be condidered as well. With an "inline helper" second pump you can't run it only on demand, triggered by a hodds switch. It has to run constantly with the intank pump. This will produce an increased flow that may be a concern at idle. The return line may become a restriction the same as if using a single large pump. The return line is only 1/4" ID above the rear axle. You will know if you have a return flow problem if you can't adjust your fuel pressure down low enough at idle.
I have been using large external pumps myself and have desigend and installed systems on other cars. I believe that fuel and wiring are a couple of places that you don't want to cut corners on.
For external pumps, I like Magna Fuel. They are E-85 compatible and have 3 pumps that will work on our cars for continous duty. They are 1000, 1500, and 2000 HP rated for gasoline. I use the 1500 HP one with a stock style adjustable FP reg, but modified return line.
We used to run an "inline" pump as a second pump years ago. It was very common in those days before the newer higher capacity "Intank" pumps became available.
There are always going to be some issues when you start to add complications. The K.I.S.S. principal might be more applicable to cars like ours that are already more complex than normally aspirated toys.
Some things to consider is what would occur if one of the two pumps were to become degraded even slightly? What effect would that have on the system? Would there be a difference depending on which pump? How would the flow rate at pressure be compared in order to select the proper match? What would happen if one of the pumps failed?
The rest of the system should be condidered as well. With an "inline helper" second pump you can't run it only on demand, triggered by a hodds switch. It has to run constantly with the intank pump. This will produce an increased flow that may be a concern at idle. The return line may become a restriction the same as if using a single large pump. The return line is only 1/4" ID above the rear axle. You will know if you have a return flow problem if you can't adjust your fuel pressure down low enough at idle.
I have been using large external pumps myself and have desigend and installed systems on other cars. I believe that fuel and wiring are a couple of places that you don't want to cut corners on.
For external pumps, I like Magna Fuel. They are E-85 compatible and have 3 pumps that will work on our cars for continous duty. They are 1000, 1500, and 2000 HP rated for gasoline. I use the 1500 HP one with a stock style adjustable FP reg, but modified return line.
Boost-a-pump or Volt booster
There is a difference between these two items.
The volt booster allows full output from your alternator controlled by a hobbs switch for boost conditions. This will be only a couple of volts.
The Boost-a-pump supplies the power power level increase from input voltage (adjustable up to 150%) to the fuel pumps or other components. I think Jim Bell makes on for ignitions as well.
There is a difference between these two items.
The volt booster allows full output from your alternator controlled by a hobbs switch for boost conditions. This will be only a couple of volts.
The Boost-a-pump supplies the power power level increase from input voltage (adjustable up to 150%) to the fuel pumps or other components. I think Jim Bell makes on for ignitions as well.
I see the two walbro's in tank pumps that could be a good choice, but don't think its E85 friendly. The DW300 pump is E85 friendly, but is just short to supply 80's at 25# boost. Don't know if the boost-a-pump can get me there, but you won't know unless you try I guess. The inline pump could be an option, but I think I want it to be the last resort.
So the boost-a-pump makes more volts just to the pump and a volt booster gives 2 or so more volts to everything. Why not just run both wouldn't that be better or could that cause a problem? Does the boost-a-pump take alot of amps to run, could it make my alt work harder and rob me from some hp?
Otes.
So the boost-a-pump makes more volts just to the pump and a volt booster gives 2 or so more volts to everything. Why not just run both wouldn't that be better or could that cause a problem? Does the boost-a-pump take alot of amps to run, could it make my alt work harder and rob me from some hp?
Otes.
I could make a better choice if I knew how many l/ph I need the pump to produce at ya many volts if I'm running 80's with 25# boost. I don't know how to figure this out so if anyone out there could help out. I get the 43 + boost for fuel pressure, but thats it don't understand what else goes into it. That should help in picking the right set-up dual pumps, single pump with boost-a-pump or duals with boost-a-pump.
Thanks, Otes.
Thanks, Otes.
Check KevinB's thread in this section if you haven't already. He started out with a pair of 307 walbros on a homemade dual hanger in tank, Stock lines feeding 96's I believe. No volt booster or boost a pump and went pretty far.
I have dual 340,s feeding 120's through Stock lines and will see how far I can go before I upgrade the feed and return lines.
Jury is still out on e85 compatibility with 340 pumps. Some folks have 5 years on their fuel system with no issues.
I have dual 340,s feeding 120's through Stock lines and will see how far I can go before I upgrade the feed and return lines.
Jury is still out on e85 compatibility with 340 pumps. Some folks have 5 years on their fuel system with no issues.
Figuring fuel requirements
The standard gasoline fuel consumption for NA cars is aprox 1/2 pound per HP. That is usually just stated as 2 HP per pound.
The safe starting place to estimate the needs of our turbo cars is aprox .65 pounds per HP. That can be easily rounded to aprox 1.5 HP per pound.
The ability to deliver the safe estimated amount of fuel is a good place to start, although you will possibly end up tuning leaner, for less actual fuel consumption.
Gasoline weighs aprox 6 lbs per gallon.
One gallon = 3.8 liters. Hmmm theres a number we are all familiar with.
Do the math and make a reasonable estimate of your maximum fuel needs, for both now and in the future. Don't be overly optomistic about the manufacturer's claims until verified. These will be subject to the degradation of age and wear as well over time.
Check out the MGNTA.COM site for tech articles. There is one there "Max Boost #2" that outlines the procedure for checking your cars fuel delivery.
The standard gasoline fuel consumption for NA cars is aprox 1/2 pound per HP. That is usually just stated as 2 HP per pound.
The safe starting place to estimate the needs of our turbo cars is aprox .65 pounds per HP. That can be easily rounded to aprox 1.5 HP per pound.
The ability to deliver the safe estimated amount of fuel is a good place to start, although you will possibly end up tuning leaner, for less actual fuel consumption.
Gasoline weighs aprox 6 lbs per gallon.
One gallon = 3.8 liters. Hmmm theres a number we are all familiar with.
Do the math and make a reasonable estimate of your maximum fuel needs, for both now and in the future. Don't be overly optomistic about the manufacturer's claims until verified. These will be subject to the degradation of age and wear as well over time.
Check out the MGNTA.COM site for tech articles. There is one there "Max Boost #2" that outlines the procedure for checking your cars fuel delivery.
This is how you can do it graphically. You basically plot the pump (supply) flow characteristics on the same graph as the injector (demand) flow characteristics. If the intersection of your desired max operating fuel pressure and the curve of your particular injector fall within (to the left of) your particular pump curve, then fuel pressure should be maintained at WOT and you should have adequate fuel flow capacity. This plot assumes 100% injector duty cycle, gasoline alone (no alky), and no system losses (fuel lines, etc.) - so allow for some safety margin. You can also do this numerically (with numbers, data), just calculate so that you have more fuel supply than the injectors are expecting at your particular operating pressure.
Graphical example: Suppose you have a DW300 pump and can supply 18 volts to it (a booster, obviously). And you have 6 of 85 #/hr injectors. You want to run 45 psi of base fuel pressure and 25 psi of boost - so max operating fuel pressure is 45 + 25 or 70 psi. Find the 85# (@25 psi) injector curve, see where it crosses 70 psi - looks like about 86 gph. Find the DW300, 18v pump curve, see where it crosses 70 psi - looks like about 96 gph. So it looks like in this particular example, there is roughly 10 gph excess fuel capacity (assumes no system losses, again remember the injectors are at 100% dc - you would really want to run them at less dc so the actual inj fuel demands will be less).
Side note: The only 18v DW300 pump data I could find was from the manufacturer (who sells this pump) so take those numbers with a grain of salt - I don't have any independant test data to back those figures up.
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I know this cn be mathematically argued against and I'm looking forward to any responses to this post but.....I've converted quite a few TR's to E85, even back when nobody would listen to one word about the benny's of E85 in or cars. For most street applications, a Hotwired Red's or 340 does the job on a mid level set up. I've been careful to watch for lean conditions and so far have not seen any problems. Most of this is becuase in the whole scheme of things, people dont make the power they think their cars do. For those who race their cars more than cruise them, it's more important to supply fuel for high RPM runs.
I would just use your existing set up and see how far it takes you before you spend a lot of money. Then once you find you dont have the fuel supply necessary, start finding and using other options. This is just my opinion. ----Jeremy
I would just use your existing set up and see how far it takes you before you spend a lot of money. Then once you find you dont have the fuel supply necessary, start finding and using other options. This is just my opinion. ----Jeremy
Sorry, I know this is kinda a dated thread at this point, but I read this and need to mention this.... The Walbro high pressure 255lph pumps work just fine with E-85. Now, I know they say that they aren't e-85 compatible, but I have a Mitsubishi Evolution running an intank double-pumper with two Walbro 255s (just recently switched them out to the new Walbro 400lph pumps). Guys in the Evo community have been using these pumps with E-85 FOR YEARS with no problems whatsoever....
oddiesGN,
Did you ever make a decision on which way to go? As I posted earlier I have the exact same situation as you. I will be running 80lb injectors on a stock ecm and E85 looking for 23-25lbs of boost. I have narrowed it down to the TT340 pump from TurboTweak with a boost a pump or the Racetronix dual pump setup. However, if I go with dual pumps, I want them running all the time, not operating off a switch. If I'm going to rely on a pressure switch I'll just stick with the BAP I already own.
Did you ever make a decision on which way to go? As I posted earlier I have the exact same situation as you. I will be running 80lb injectors on a stock ecm and E85 looking for 23-25lbs of boost. I have narrowed it down to the TT340 pump from TurboTweak with a boost a pump or the Racetronix dual pump setup. However, if I go with dual pumps, I want them running all the time, not operating off a switch. If I'm going to rely on a pressure switch I'll just stick with the BAP I already own.
Racetronix
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We have NEVER had a Hobbs switch fail but if you are concerned about it consider putting two in parallel. Running both pumps all the time puts unnecessary heat into the fuel and load on the electrical system. Running both pumps all the time will require an upgraded -6 return line.
696
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For what it's worth, Friday I ran 25-26 psi of boost with 0 knock and 90% DC. E-85, stock fuel lines (bored out), 80's and a TT340. I had some variance while boost was building but once it was maxed out only 90%.
696
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Old PT 51, bone stock heads (and motor). No volt booster or boost a pump. I do have a Racetronix Hotwire, mid connection and in tank wire upgrade.
BEATAV8
The Engine Whisperer
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The fuel pressure on my ride did not look pretty when I was running double pumpers with stock fuel lines. It had plenty of pressure, but there was a stability issue. I had to switch to less restrictive fuel lines.
