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Old 07-09-16, 11:08 AM
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Skeese’s E85 Fuel System for 750 RWHP Thread

Aaaaaaaallllllllrighty guys. I’ve recently made a deal on a semi-p motor and an EFR 9180 setup to go with it which I expect to see 30 PSI on E85, so I am going to need a LOT more fuel! Given this high horsepower level there can’t be any fueling mishaps so I want to do it right the first time. I won’t be getting my hands on the motor/turbo until December so I’ve got plenty of time to prep my car for the upcoming big power and given the cost of lines, fittings, pumps, filters, injectors, and rails I’ve decided this is going to be a measure 500 times and cut once kinda deal.

I want to build the fuel system to support 750 rwhp. I’ve seen several semi-p/9180 dyno sheets where this setup has been close to the 600 rwhp mark at 18 PSI so I feel this is a good number to use for mathematically sizing my fuel system components. I’ve spent a good amount of time reading various threads on here regarding sizing, but want to lay out my plan for comments and suggestions before I pull the big dollar trigger on all of this stuff.

At this point my goals for this system are
• Support 750 RWHP @ 30 PSI
• Keep the stock FD fuel tank
• Run a FlexFuel Sensor and retain the ability to use 93 octane fuel if required (for the purpose of limping it somewhere if I have to)
• Use all PTFE fuel line
• Have at minimum a 15% safety factor on max fuel flow
• No fuel components are to be located in the hatch
• Easy filter changing ability

So before we get started I have my first question. I ended up getting a great deal on 32’ of Aeroquip -6AN PTFE hose and 15’ of the matching -8AN hose and all along assumed I’d be using Aeroquip PTFE fittings. After some post-hose-purchase research I came to find out they only make their PTFE fittings in steel and they don’t offer any aluminum ones. I would personally prefer to stick with aluminum fittings, so my question is will Fragola fittings originally designed for use with the Fragola 6000 series PTFE hose work with the Aeroquip Teflon hose? I’ve read mixed things online about compatibility. If not, is there any other aluminum fitting options that would be better suited for this hose?



Aeroquip -6AN Hose:
• ID = .32” OD = .43”
• 4” Minimum Bend Radius
• Stainless Steel Wire-Braid Cover
• Teflon Inner Tube

Fragola 6000 Series -6AN PTFE Hose:
• ID = .312” OD = .505”
• 6.5” Minimum Bend Radius
• Includes clear plastic cover on top on the stainless braided line (I’m assuming this is where the extra .075” OD comes from).


I’ve been using Solidworks to map out the system and parts that are going to be required. While a hand drawn sketch would likely work, I’ve got the time and I enjoy the CAD. I started planning with the fuel tank sump, since that will be where the fuel flow starts. I found that summit racing carries the Competition Engineering fuel tank sump kit for $68 which has two ˝” NPT ports. From here I’ll use set of ˝” NPT to -8AN adapters to convert to the two -8AN PTFE AN hoses that are going to run to the pre-pump filters. I don’t remember exactly how I came across it, but I found that XRP makes a 120 micro strainer that will couple directly in line with the -8AN hose end and the Bosch 044 fuel pump’s M18X1.5 inlet. I emailed with XRP and confirmed that this little guy has a stainless steel filter, is rated for use with E85, are capable of 16.7 GPM each when clean, and have a 1 PSI pressure drop across the filter. Oh, and the kicker here is they are only $54 from ANplubming.com. Seems like a legit deal.



My next question is about the check valve. Is a check valve needed? I've never seen anybody using one, or maybe I've just overlooked it. Is there any benefit to using one? I can see how it would serve to protect the pump, but again I don't know if it is really necessary.



From here I am going to be extremely original and use a set of Bosch 044 fuel pumps. I’ll buy a mounting bracket or make my own and mount the pumps on the side of the tank. In my research about the XRP fuel filter I came cross this check valve adapter which they recommend be used so as to eliminate the need for a check valve later in the system, however I have never heard of a check being used. Is this necessary or is there any reason to buy them/not buy them? From the twin 044 discharge ports I’m thinking I’ll run them into a rail and then out into a -8AN line that will run to the engine bay.










Any comments/suggestions/input is welcome! I'll once I get through the questions in this initial setup I'll post my engine bay modeling as well as the math (based mostly on the Howard Coleman threads on here). I'm not entirely sure how well the mathematically calculated injector and fuel pump flow requirements reflect the actual fueling needs of a 13B for XXX RWHP, but I've go the time to figure it out.

Cheers guys, enjoy the weekend!

-Skeese
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Old 07-09-16, 01:27 PM
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750 rotary rwhp SAE E85

750 X 1.92 = 1440 CFM / 14.471 = 99.5 pounds per minute of air

the EFR 9180 makes just under 95.

at 30 PSI you will be in the 90 pound area.

figuring for 95 which is tops...

95 at 10.0 AFR is 9.5 pounds per minute of E85.

9.5/ 6.54 = 1.45 Gallons per minute = 5489 CC/Min

5489 X 1.35 (lag and duty) = 7410 X 1.35 (adj to E85) = 10,003 call it 10,000

10,000 Gross injector requirements for 750 E85 3 Bar static pressure 10.0 AFR

you probably already worked that out.

while i appreciate your setup and it will probably work fine i would go a different route as i don't like the rail as a joining item. Kenne Bell has done extensive fuel system research and states you lose 20 to 30 % flow by joining two pumps. (go to their excellent tech section).

not only do you need a lot of fuel but your fuel pumps will be going against 30 psi of boost pressure so you will be needing to look at pumps at the 73.5 pressure on the flow charts. most are headed south at that point.

since you are in the one percentile of power at 750 i suggest you look at Fuelab offerings. after you do that call Rob Scharfenberg Chiel Engineer and have a chat. if you don't do Fuelab i strongly suggest you run whatever pumps you decide on at 16V using a Kenne Bell Boost A Pump.

good luck,

Howard
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Old 07-09-16, 02:02 PM
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I recommend searching "Radium Ultimate Fuel Pump test" as well as Fuel lab as HC mentioned
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Old 07-09-16, 04:23 PM
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Radium has a well engineered spread of fuel pump mounting items and surge tanks. i note their fuel pump test ended up pretty much like my thread Fuel Pump Options... the Walbro E85 and Gas pumps leading the way in the popular price category.

Fuelab is a few clicks above both as to performance and well as cost, but when you are suiting up for 750 hp...

hopefully you can log Differential Fuel Pressure.
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Old 07-09-16, 04:55 PM
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i have an idea, and feel free to shoot it down, as i have no idea how easy this would be to implement this in real life.

why not run 2 fuel systems? basis for the idea is Howard not liking that manifold linking the two pumps

use the factory lines, in tank pump setup etc, but only run it to the primary fuel rail.

then, for the second pump, it then runs though the sump, with a second set of lines etc to the secondary fuel rail.

the pro's are that each fuel system is pretty optimal for flow, and of course you can shut off the secondary side when its idling/cruising. cost shouldn't be too bad, as you use existing (reliable!) stuff for half of it.

the con of course is that its complicated, and you basically have 2x the failure points. space might be a problem too.
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Old 07-09-16, 06:25 PM
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Hey Howard. I was hoping you would catch this thread.


Quote:
Originally Posted by Howard Coleman CPR View Post
750 rotary rwhp SAE E85

750 X 1.92 = 1440 CFM / 14.471 = 99.5 pounds per minute of air

the EFR 9180 makes just under 95.

at 30 PSI you will be in the 90 pound area.

figuring for 95 which is tops...

95 at 10.0 AFR is 9.5 pounds per minute of E85.

9.5/ 6.54 = 1.45 Gallons per minute = 5489 CC/Min

5489 X 1.35 (lag and duty) = 7410 X 1.35 (adj to E85) = 10,003 call it 10,000

10,000 Gross injector requirements for 750 E85 3 Bar static pressure 10.0 AFR

you probably already worked that out.
I worked out these same numbers last week at work while going over your thread where you were using 600hp as an example. On the front end, I'll be using a set of ID1000's in the primary position and 4 ID2000's in a 4 port FFE rail.

ID1000's = 1015 CC/Min @ 43.5 PSI X 2 = 2030 CC/min
ID2000's = 2225 CC/Min @ 43.5 PSI X 4 = 8900 CC/min

2030+8900 = 10,930 CC/min > 10,000 CC/min by 8.5%. Not quite my target 15% but the cost of going from the ID1000's to the 1300's or 1700's is HIGH.

Quote:
Originally Posted by Howard Coleman CPR View Post
while i appreciate your setup and it will probably work fine i would go a different route as i don't like the rail as a joining item. Kenne Bell has done extensive fuel system research and states you lose 20 to 30 % flow by joining two pumps. (go to their excellent tech section).

not only do you need a lot of fuel but your fuel pumps will be going against 30 psi of boost pressure so you will be needing to look at pumps at the 73.5 pressure on the flow charts. most are headed south at that point.

since you are in the one percentile of power at 750 i suggest you look at Fuelab offerings. after you do that call Rob Scharfenberg Chiel Engineer and have a chat. if you don't do Fuelab i strongly suggest you run whatever pumps you decide on at 16V using a Kenne Bell Boost A Pump.

good luck,

Howard
I'll have to look into that data about the conjoined pumps losing flow. I don't understand why that would be. I did read the fuel pump comparison article that radium engineering did and it was for this reason I was leaning towards the 044 pumps. While the fancy new walbro's flow a good bit more fuel at 43.5 PSI the fuel flow drops off quickly as the boost goes up. The 044 however appears to push damn new the same amount of fuel at 3 bar as it would at 5 bar (~73 PSI so what I would need at 30 PSI of boost).



This all being said I really don't want to add the boost a pump into the system. As a mechanical engineer I don't like the idea of driving a fuel pump beyond the electrical voltage it was intended to run at. I have to think this would cause extra wear on the pump and ultimately increase the potential for failure. I know there are cases time and time again where this has not happened, but I personally don't like that idea.

I will however be looking into the fuel lab components. Given simplicity is part of my goal it would be excellent to run a single large pump. I'll be giving Rob a call next week to get a better understanding of the way the prodigy fuel pump works with the electronic fuel pressure regulator. While the fuelab setup is expensive, so is buying a new set of 044's and tacking on two of everything needed to support them.

Thanks for the input

-Skeese
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Old 07-09-16, 06:29 PM
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Quote:
Originally Posted by j9fd3s View Post
i have an idea, and feel free to shoot it down, as i have no idea how easy this would be to implement this in real life.

why not run 2 fuel systems? basis for the idea is Howard not liking that manifold linking the two pumps

use the factory lines, in tank pump setup etc, but only run it to the primary fuel rail.

then, for the second pump, it then runs though the sump, with a second set of lines etc to the secondary fuel rail.

the pro's are that each fuel system is pretty optimal for flow, and of course you can shut off the secondary side when its idling/cruising. cost shouldn't be too bad, as you use existing (reliable!) stuff for half of it.

the con of course is that its complicated, and you basically have 2x the failure points. space might be a problem too.
Interesting idea, but the overall complexity of it wouldn't be ideal. I'm trying to build as simple of a system as possible with as few failure points as possible. It would only take one failure and boom...goodbye really expensive motor and really expensive turbo.


Which leaves me wondering, does anybody have any input on the fittings? I just left a car meet and was talking to a v8 rx7 friend about it there who had a couple horror stories about some mismatched hoses/fittings. I would like to figure this out first and foremost so I can start the process of buying new stuff and selling my stuff if I have to.

-Skeese
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Old 07-09-16, 09:23 PM
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I will be "sumping" my fuel tank, and will run the now internal Bosch 044, in an external setup once the fuel tank gets its sump. I would recommend full race sump "tank", as its only 1 inch (height) at its tallest part. That means that when added to your OEM tank, it wont sit as low, which helps with the fuel pump placement, as the fuel pumps should not sit (or mount) higher than the lowest point of the tank/sump port (that's what I've read anyways). Here's the link to ti the full race sump kit:

Fuel Sump Kit - Full-Race.com

Like you, I don't like the idea of a boosting the voltage to the pump, mainly because its one more thing that could fail, and I like the simpler is better approach (well sort of lol)

Not that I have any experience, or knowledge, but I've seen what racers use and what works for them, and I can tell you that Weldon and Magnafuel are two of the brands that I've noticed that racers use. I've browsed the Magnafuel site/external fuel pumps, and these ones have caught my attention:

ProStar EFI Series* |MagnaFuel

Now, if you do want to use the good old bosch 044 (which I might do too, since I already have on in the gas tank), I have concerns about overheating the pump if used externally.
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Old 07-09-16, 10:11 PM
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Quote:
Originally Posted by Skeese View Post
I'll have to look into that data about the conjoined pumps losing flow. I don't understand why that would be.

-Skeese
have a read through the Kinsler catalog, they don't like sharp bends, and things like that, so your pump to fuel rail is right out. it should be a Y fitting.

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Old 07-10-16, 07:32 PM
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I can't tell you much about this, but there's a new pump in development that can handle ~670lph (11k+ CC/Min and EASILY handle your 10k CC/Min @ higher base fuel pressures.

So my solution would be 6 x ID1700s (2 on Primaries, 4 on Secondaries) and 55psi base pressure (1950 CC/Min). 30psi boost is only 85psi at the pump + losses (so let's say 90psi at the pump), in which it could still handle your flow requirements.

I don't mind if you copy my setup with fuel filtration, and with e85, water filtration is pretty important too.

The ID1700s are made for this. 1000s and 2000s are amazing injectors, but you're asking a lot from them with a fuel they aren't specifically designed for.
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Old 07-10-16, 08:43 PM
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I read through and did not see it answered, but the check valves are there to keep pressure in the lines when the key is off. Factory fuel pumps have them built in to lessen cranking time. With that injector size, you do not want to be cranking from 0psi and building to 43psi. The check valve helps with all of that.
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Old 07-10-16, 08:43 PM
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Quote:
Originally Posted by KNONFS View Post
I will be "sumping" my fuel tank, and will run the now internal Bosch 044, in an external setup once the fuel tank gets its sump. I would recommend full race sump "tank", as its only 1 inch (height) at its tallest part. That means that when added to your OEM tank, it wont sit as low, which helps with the fuel pump placement, as the fuel pumps should not sit (or mount) higher than the lowest point of the tank/sump port (that's what I've read anyways). Here's the link to ti the full race sump kit:

Fuel Sump Kit - Full-Race.com

Like you, I don't like the idea of a boosting the voltage to the pump, mainly because its one more thing that could fail, and I like the simpler is better approach (well sort of lol)

Not that I have any experience, or knowledge, but I've seen what racers use and what works for them, and I can tell you that Weldon and Magnafuel are two of the brands that I've noticed that racers use. I've browsed the Magnafuel site/external fuel pumps, and these ones have caught my attention:

ProStar EFI Series* |MagnaFuel

Now, if you do want to use the good old bosch 044 (which I might do too, since I already have on in the gas tank), I have concerns about overheating the pump if used externally.
I do like the idea of the lower profile sump. I'll keep this in mind either way but it would be for sure the best option I end up going with the fuelab single pump setup.

Quote:
Originally Posted by j9fd3s View Post
have a read through the Kinsler catalog, they don't like sharp bends, and things like that, so your pump to fuel rail is right out. it should be a Y fitting.

Kinsler_Handbook_32
I was thinking what Howard was saying that combining the flow of the two pumps was what caused the flow loss, not the bend. I only liked the idea of the rail as it seemed to me it would be less likely to leak.

Quote:
Originally Posted by SirLaughsALot View Post
I can't tell you much about this, but there's a new pump in development that can handle ~670lph (11k+ CC/Min and EASILY handle your 10k CC/Min @ higher base fuel pressures.

So my solution would be 6 x ID1700s (2 on Primaries, 4 on Secondaries) and 55psi base pressure (1950 CC/Min). 30psi boost is only 85psi at the pump + losses (so let's say 90psi at the pump), in which it could still handle your flow requirements.

I don't mind if you copy my setup with fuel filtration, and with e85, water filtration is pretty important too.

The ID1700s are made for this. 1000s and 2000s are amazing injectors, but you're asking a lot from them with a fuel they aren't specifically designed for.
ID doesn't seem to think E85 is an issue with ID1000/2000's.

Fuel Compatibility – Compatible with Methanol/Ethanol/All Known Hydrocarbon Fuels. - ID1000/2000 spec sheet listed on the ID page for each injector.

I recently pulled a set of ID2000's that I had been running E85 for over a year and they looked just fine. I'm sending them to ID for general inspection and servicing tomorrow so I'll let them be the judge.


THAT ALL BEING SAID, does anybody have an answer to the fitting/hose question??

-Skeese
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Old 07-10-16, 08:57 PM
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Quote:
Originally Posted by Skeese View Post

THAT ALL BEING SAID, does anybody have an answer to the fitting/hose question??

-Skeese
The main thing I have read has been about the manufacture of the fittings themselves. Example, Earl's fittings are among the best on the market. I have read that they have larger internal passages than an eBay fitting.

As far as mixing the hose to the fittings, you have the option of buying a single fitting and cutting off a length and checking the fit and assembly. Really, the only way I know short of contacting the makers of the hose and fittings directly.
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Old 07-10-16, 09:32 PM
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Quote:
Originally Posted by ACR_RX-7 View Post
The main thing I have read has been about the manufacture of the fittings themselves. Example, Earl's fittings are among the best on the market. I have read that they have larger internal passages than an eBay fitting.

As far as mixing the hose to the fittings, you have the option of buying a single fitting and cutting off a length and checking the fit and assembly. Really, the only way I know short of contacting the makers of the hose and fittings directly.
I'll call both Aeroquip and Fragola tomorrow, and Earl's as a backup to Fragola but I expect they will all just suggest I use their hose with their fittings. I don't want to test fit each as they are expensive and I think it either is or is not a good idea to mismatch them.

I'll also be calling Fuelab and ID. I want to have a plan by the end of this next week so I can start ordering.

-Skeese
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Old 07-10-16, 09:36 PM
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Aeroquip also offers the fittings in stainless steel, if that's your thing.
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Old 07-10-16, 09:47 PM
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Quote:
Originally Posted by ACR_RX-7 View Post
Aeroquip also offers the fittings in stainless steel, if that's your thing.
They only offer a handful of fittings in stainless steel, most of which are the smaller -3 and -4AN sizes. Given what they want for these tiny stainless fittings I can only imagine if they did offer the -6 and -8AN ones I need, the complete order would be worth more than my car currently is.
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Old 07-10-16, 09:56 PM
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the complete order would be worth more than my car currently is.


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Old 07-10-16, 10:29 PM
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I did the in tank '044 with no check valve and its a pain in the *** on a street car.

You have to flick the key over to on to prime the system back and forth once and then start the car to get it to start right away.

This isn't an issue with a basic race car where you flick the fuel pump "on" switch and the pump is then running and then you start the car.

But it is safer for wrecks/fires running the pump through the ECU so it only runs with the key in the "on" position and with engine rpms sensed by the ECU.

Check valve it!

Next time I do a fuel system (probably the FD) I want to just use the two stock fuel lines to the two rails (primary & 2ndary) both as feeds from dual '044s with the regulator back at the tank dumping right in (like a Corvette) so I don't have to run another return line.

Or use both stock lines with a pump each as feeds and use PWM for fuel pressure through the ECU if I get a bad *** ECU.
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Old 07-12-16, 08:32 AM
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i want to run dual fuel systems with 87 octane in the primary tank and e85 in the spare tank. the ms3pro i have supports turning off the primarys at staging. so all i need is two fuel lines and two return lines. the spare tank i have is from an 04 m45, it was behind the read seat, so it would fit the hatch of the fc well. i've been thinking this over for a while.
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Old 07-12-16, 11:34 AM
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FWIW, think two stock hard lines would be less failure prone than one PTFE line. Steel is sturdier than rubber/plastic and two lines would provide some redundancy. If one goes down, at least you have some fuel whereas with one line your SOL. You can also push more fuel in less physical space. Also, should be easy to mount another line next to the existing. The return line would probably need to be resized tho.

No experience, just an opinion
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Old 07-13-16, 08:23 AM
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I'm currently using 3 different brands of PTFE Fittings on my Earls Speed Flex line and None of them are leaking. You can feel it when you assemble them. If it feels loose... The Stainless Fittings will get hot. If I could do it all again..the one and ONLY thing I would change would be to use all XRP fittings. I used 3 of them on my set up and I remember the feeling of "WTF...Thats it?...That Easy" when I assembled them compared to the other fittings. I built my set up with (6) I.D1300's... But We ran out of Inj on the Dyno at 8300 RPM (Trying to spin to 9kish). I'm actually selling my 1300's right now and going with (6) 1700's.
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Old 07-13-16, 08:34 AM
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Quote:
Originally Posted by Howard Coleman CPR View Post
750 rotary rwhp SAE E85

750 X 1.92 = 1440 CFM / 14.471 = 99.5 pounds per minute of air

What is the 1.92 number and how did you come to that

the EFR 9180 makes just under 95.

at 30 PSI you will be in the 90 pound area.

figuring for 95 which is tops...

95 at 10.0 AFR is 9.5 pounds per minute of E85.

do you mean Gasoline here? You have the E85 1.35 factor later in the calculation

9.5/ 6.54 = 1.45 Gallons per minute = 5489 CC/Min


Where does the 6.54 number come from, is it simply a conversion factor?


5489 X 1.35 (lag and duty) = 7410 X 1.35 (adj to E85) = 10,003 call it 10,000

In your fuel pumps 2014 thread you had lag at 13% and then duty at 85% leaving a 15% safety margin, where is the 1.35 number from?

Also here you have another 1.35 fro the adjustment to E85. In your other fuel pumps 2014 thread you had stated "E85 has 82,293 per gallon V gas at 116,090 so multiply gas times 1.41 for E85"

82,293/116,090 = 1.41. Is this not to be the figure for the E85 adjustment?


10,000 Gross injector requirements for 750 E85 3 Bar static pressure 10.0 AFR

Howard
In reading back through this and looking at my calculations for the required flow I had some questions regarding your numbers and units? I'd just like to better understand where the numbers came from and the units involved so I can link each calculation together. I want to have all my numbers solid before I start calling fuel pump chief engineers.


-Skeese
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Old 07-13-16, 09:20 AM
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750 rotary rwhp SAE E85

750 X 1.92 = 1440 CFM / 14.471 = 99.5 pounds per minute of air

What is the 1.92 number and how did you come to that.

A fair question.

1.92 is the amount of CFMs to make one rotary RWHP SAE. I picked it up around 14 years ago from someone and use it because it works. I assume it was empirically derived. As in many math tools we use there probably is some wiggle in it but it is an extremely helpful tool and has proved very accurate over the years.

the EFR 9180 makes just under 95.

at 30 PSI you will be in the 90 pound area.

figuring for 95 which is tops...

95 at 10.0 AFR is 9.5 pounds per minute of E85.

do you mean Gasoline here? You have the E85 1.35 factor later in the calculation.

You are correct raising a question here… the last word should have been “fuel.”

9.5/ 6.54 = 1.45 Gallons per minute = 5489 CC/Min


Where does the 6.54 number come from, is it simply a conversion factor?

I use 6.54 for E85 weight per gallon.

5489 X 1.35 (lag and duty) = 7410 X 1.35 (adj to E85) = 10,003 call it 10,000

In your fuel pumps 2014 thread you had lag at 13% and then duty at 85% leaving a 15% safety margin, where is the 1.35 number from?

1 = fuel before lag and duty
1 – 13% = .87 adjusts for lag (lag of course can be more or less so it is an est)
.87 X .85 = .74 adjusts for 85% duty
1/.74 = 1.35


Also here you have another 1.35 for the adjustment to E85. In your other fuel pumps 2014 thread you had stated "E85 has 82,293 per gallon V gas at 116,090 so multiply gas times 1.41 for E85"

82,293/116,090 = 1.41. Is this not to be the figure for the E85 adjustment?

The relationship between BTUs and power in the rotary is still a bit muddy and can be figured a number of ways. BTUs is certainly one way but empiricism generally rules as other factors come into play.

BTUs is 1.41 but 1.35 is used by many. I find my results closer to 1.35 but don’t have enough data to settle on a number. If it ends up closer to 1.35 my guess is something in the fuel is lowering the conversion of the BTUs to power. beyond my pay grade at that point but I am very interested in getting a solid rotary conversion number and should have it within a month.

10,000 Gross injector requirements for 750 E85 3 Bar static pressure 10.0 AFR
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Old 07-15-16, 06:20 PM
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Thanks for clarifying the numbers Howard. It all makes sense to me now.

Last edited by Skeese; 07-15-16 at 10:35 PM.
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Old 07-15-16, 06:39 PM
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Sounds like a good gameplan. I was going to spout off and say you should make sure the pump is safe to run on a duty cycle, but I went ahead and saw that is exactly what the pump is designed to do. Since that is the case, I think it will be a far more modern style of fuel system than the usual return style system.

I know from experience that E85 doesn't like to be returned to the tank after getting heated up by hot fuel rails and an engine bay.
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