Fuel cell set up
Posted 02 September 2017 - 12:54 PM
Thanks in advance
Posted 02 September 2017 - 05:16 PM
You can't hang if your nuts haven't dropped...it's physics
Posted 02 September 2017 - 06:06 PM
Posted 02 September 2017 - 09:24 PM
Size depends on what you have for room.
Make note of inlet and outlet locations. And if it's baffled or not don't know if that matters.
Fuel pump, needs to be enough to feed the motor... Carter makes a bunch of good pumps at different psi ranges....
Might want a fuel pressure regulator with a return.... I used a Holley one, good product for the money...
And fuel line? What size do you have and do you have a return line?
You might need upgrade to a 3/8 od feed line then use the old line as return....
All this depends on your motors needs...
Posted 03 September 2017 - 11:54 AM
Aluminum or plastic fuel cell?
I like to mount the fuel pumps in the tank. They run quieter, cooler and last longer that way. Tanks, INC offers generic fuel pump mounting brackets for custom in-tank applications. With a pump, the PA4 setup is only about $225 from Summit Racing.
I would also consider (as Crash mentioned) bending a new 3/8 hard line, but not just for size. 3/8 hard line will allow you to use -6 AN tube nuts, making the transition from the tank to the engine easier with off the shelf AN fittings.
Posted 04 September 2017 - 09:44 AM
Are you buying a fuel cell or a replacement generic tank that they call a fuel cell? The typical aluminum or plastic "fuel cell" for a couple hundred $s is no better than a stock tank. Its a single wall fuel tank that just doesn't fit as well as the original, and will likely end up with a higher center of gravity.
If you;re doing it to have an installed high pressure pump, make sure it has an internal baffle to keep the pump submerged when fuel is splashing or you'll run into constant starvation issues. Too expensive, but look at what Aeromotive makes and how theirs is assembled.
Tanksinc.com also makes EFI swap tanks, and I'm sure others. Make sure your return line is larger than your supply line to cool the fuel on its return trip, as well as to reduce aeration in the tank. They also have a great tech site with fuel line schematics.
Posted 04 September 2017 - 10:10 AM
Good point. These terms get thrown around these days without abandon.
I can understand wanting a generic aluminum fuel tank as most people don't actually need a racing fuel cell. As long as you have a good place to mount it and are aware of the proper ways to mount them, aluminum tanks are a good alternative to a stock tank (I have one in my '57 Land Rover).
But if you're talking about a plastic tank, I don't like those at all.
The Tanks, INC fuel pump brackets have a sump built in,, which makes them a good all around unit.
Posted 04 September 2017 - 11:37 AM
There is a lot of questions that you haven't asked, and a lot of info you haven't provided.
Being a DET, what power (how much boost) are you wanting to run?
That determines what size injectors you will need, and what size pump you will need to run.
Also if you can get away with keeping the stock pressure regulator.
Walbro makes EFI pumps that will handle the SR, go to their US distributor www.fuelpumps.net.
Do NOT, repeat, Do NOT buy a Walbro off eBay, or any on-line shop, as 90% of them are selling chinese copies, that will not deliver what they claim, and will fail, and could very well cook your pistons.
FuelPumps.net has a whole page on the fakes.
Just like the fake Bosch 044 pump, the chinese are selling copies of them also.
They just do a better job with markings on the Walbro, so they are harder to spot.
Check with the 240SX guys for exact numbers, but I believe factory fuel pressure is around 35-40 psi, and that is what your stock regulator (mounted on your fuel rail) will produce.
Unless you are trying for over 500 hp, the Walbro 255HP is a good place to look.
Either an in-tank, or in-line version.
Factory fuel line size for the SR is typically 8mm, so 6AN will handle all the fuel you will need just fine, both pressure & return.
There are pleanty of 600 hp Supras running off stock 8mm fuel lines just fine.
Most cells come with baffling foam, so slosh won't be a problem, but it turns to shit with age, so plan on changing it out yearly, before it crumbles into little pieces, and clogs your complete system.
Which comes to fuel filters, you need one meant for EFI systems. Pleanty of them out there.
If you have deep pockets, buy a Holley Fuel Mat to fit your tank. It passes fuel, but not air. Great stuff, but pricey.
I ran an El-Cheapo plastic cell in my 521, just because Nissan wanted $400 for a stock tank, and the cell was $100.
Would never run a plastic cell on a race car. Something about putting flammable liquid in a flammable tank disturbs me.
I don't trust the aluminum box type much more.....How good of welds did the minimum wage welder do ?
There is the option of running what people call a surge tank, a small external tank just big enough to hold about a quart of fuel, and an in-tank pump.
You need a low pressure pump to keep it filled.
Any air picked up gets sent back to the tank, and the high pressure pump stays submerged all the time.
Great for keeping the stock fuel tank.
Posted 04 September 2017 - 11:52 AM
Could you install the surge tank lower than the main tank and use a 1/2" gravity fed fuel line. It would take an awful long hard corner to use up a quart of fuel.
Posted 04 September 2017 - 12:58 PM
Probably, if the line was large enough so that it would refill fairly quick.
Maybe use the OEM drain plug as the source to go to the surge tank.
Posted 06 September 2017 - 10:34 AM
I think the purpose of a low pressure pump feeding the surge tank is to make CERTAIN that air has time to rise to the top and get pushed back into the primary tank. If you rely on gravity feed, there will never be time or the ability to PUSH air anywhere, and the whole point of the surge tank is wasted. You may as well put the pump in your primary tank and skip the effort. I personally have never used a surge tank, but I can see its usefulness. I can also see how it will allow many more potential problems to arise, like a 2nd pump, more fuel connections, more electrical connections, more welds to leak, etc... In a perfect world its not necessary. Just baffle the pump in the primary tank and you're good to go, and you'll have $400+ left over to buy more fuel.
The theory of "using a quart of fuel in a hard corner" is a bit misleading. Race engines, particularly with boost, can get 1 mpg or less under hard acceleration. Take the volume of an internal pump out of that surge tank and you may now have 12-20 ounces of fuel to play with. I know how fast I can drink 12 oz. My trucks and my race car are all faster than me, and I don't run boost. I wouldn't risk it for all the reasons posted above.
Posted 06 September 2017 - 11:04 AM
the question I rarely see asked, and what I'm interested in regarding aftermarket setups is venting. I understand that there are roll-over options, but I'm not so familiar with those. Ideally, I'd like to have a carbon canister and a purge valve set up with my SR20DET swap. I think Nissan has their term for the purge valve, but I haven't researched it yet.
I still have the original canister that came with my '75 620.
I just don't want my garage or truck to smell like gasoline vapors all the time.
Posted 06 September 2017 - 11:25 AM
I think the purpose of a low pressure pump feeding the surge tank is to make CERTAIN that air has time to rise to the top and get pushed back into the primary tank.
The theory of "using a quart of fuel in a hard corner" is a bit misleading.
A sump, to hold the pump, mounted lower than the bottom of the main fuel tank, won't have any air in it.
If the 310 tank is mounted like a 510, high up over the axle, then the sump can be mounted low enough to never get air in it,
unless of course you run dry. But then no system will solve not putting enough fuel in the tank.
The surge tanks I've dealt with were over a gallon (5 liter).
Google 'SARD fuel surge tank'.
Posted 06 September 2017 - 02:02 PM
What is the reason for the fuel cell? Don't think it was mentioned.
I know nothing about this. But, I can say if you have ideas of racing anywhere, I've learned that installation of non-OEM fuel cells (and also roll cages and seats/harnesses) jumps you to a much higher level of safety scrutiny. And the details of what you're doing become important and often viewed as a greater safety risk (bubba'd) versus stock (.gov DOT oversight).
Posted 06 September 2017 - 02:23 PM
Stock fuel tanks meant for carbs don't lend themselves to turbo EFI systems very easily.
Posted 06 September 2017 - 08:24 PM
So complicated and expensive only race cars do it. Pump doesn't have to be in the tank. Why not a low mounted inline pump that is immune to surge fitted with larger diameter lines. Keep the tank full.
Posted 07 September 2017 - 09:00 AM
No, the fuel pump doesn't need to be mounted in the tank, but if you don't want to hear the noisy pump and if you want the pump to last longer, mount it in the tank.
It's not rocket science. There are a handful of companies out there these days that make retro-fit in-tank fuel pump mounting systems. From expensive machined billet aluminum to zip screwed in steel. They are so simple to use, it's almost just as easy to do the tank mod as it is to frame rail mount a fuel pump.
I use these one's in my LS swaps -
Posted 07 September 2017 - 12:17 PM
You can also modify the pickup in your stock tank to use a larger diameter fuel line and return line - if you have a good clean tank. Then use an external pump that's vibration isolated. Unless you have Stoffregen's skills - then go for it!!! I'd also figure out how to weld a box in place to prevent sloshing around the pump pickup screen. It doesn't take much to keep it submerged. 2-3" tall box?
- Stoffregen Motorsports likes this
Posted 10 September 2017 - 08:56 AM
Some say it helps with heat, but I use it for noise. This custom tank pictured has a large expanse of flat steel and with the new pump mounted to it, the resonance gets a little loud, so I Dynamat the top of the tank to cut the noise. It does work very well at cutting the noise.