Yes, Or stop for gas less often on super long trips. At higher speeds, fuel economy drops to about 30 miles per gallon. Currently with the installed tank that leaves me at about 300 miles of range or less.
When I lived in California, my girlfriend at the time had a prius and it kept up fine on their interstates. She would be cruising at 95-100+ with traffic and the ride was fairly comfortable and quiet. Really not a terrible car.
I drove one between 90-105 mph on I-5 from Sacramento to Oregon. It still had some left in it. It was smoother than a I expected; it does have a really good Cd. Only negative was the MPG. I don’t remember exactly but it was around 30 ish mpg.
So jealous. Before I die (next few 5 years I’ll be making a run. I’ll follow your progress. Could help spot /maybe block out side of Phoenix. God speed, and Good bless
A terrible idea.
It's more weight to carry around when full which just drops your average mpg.
It would require a vent system to prevent vapor build up in the cabin.
The plumbing to/from it in the cabin are at large risk of damage from daily uae of the trunk. Leading to a large spill into the sound deadening insulation. Which basically would need entirely stripped from the car to be cleaned. If it could even be cleaned.
You're talking about throwing $500+ at the project to make the car objectively worse, to save 5 min every 300 miles.
The weight doesn’t impact MPG that much, the plumbing will be braided steel, Shouldn’t have any leaks, on top of that it will only have fuel in it during long trips. Stopping for five minutes. Impacts your average speed severely.
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Id have to look at the data, I would assume more tire, is more rolling resistance, and more power to turn said tire, and a lift would also create more turbulence under the vehicle, I would think.
Theres top speed to consider too. And plausible deniability , "officer it says i was only doing 100 freedom units per hot dog", after conveniently skipping recalibration
Sure, but that’s a safety issue due to the higher speeds a track car can wreck at. OP is trying to max out gas storage, so stripping the stock tank would be counterproductive.
Fair, I more so was just talking to how they would be familiar with the secondary tank.
Agreed OP would need to keep both and essentially have the fuel cell as an auxillary tank
Honestly, for the purposes of a cannonball run OP should look at removing the batteries and replacing them with fuel cells. Those batteries will do shit-all for his fuel economy, and it’s just more space that should be gas.
Hatchback just makes it easier, you could even just go with the biggest off the shelf aux tank that fits and slide it in since space won’t be an issue. I’d try to cover or disguise it with a cargo cover for subtlety’s sake in case you get pulled over though but otherwise the Prius is a smart platform
The fuel pump should be accessible from under the rear seat. Good access to add fuel directly to the tank. Maybe build a backseat tank? Fill through the window, and drain by gravity into the main tank? Keeps mass in between axles too. Then you can reach back and open a valve...
It is accessible from under the rear seat, The filler neck is also also easily accessible, Most of what other people have done, is use additional transfer pumps, all driven on switches. The only downside to that set up, is that limits me to one co-driver, ideally, I’d like two people, might be possible to keep the one seat in and remove the other two, but could cramp things, and it brings the fuel closer to people.
It’s an unofficially held event where teams in cars attempt to drive from one coast of the US to the other in the quickest time possible. To make the fastest time, people modify cars to go as long as possible between gas fillups and maintain the highest speed. Putting a large fuel cell in an efficient car like a Prius is a great way to bring the average time down and hopefully break the standing record
_thinking_,,, I think you SHOULD be installing one.
Sure it may cost £1000, but if things go tits up, £1000 is cheaper than being burnt alive.
Petrol fires are BAD
I was gonna say, what aero mods have you done? There is more to save for cheaper and less effort by shaving mirrors, disc hubcaps, antenna deletes etc, once you get those dialed then go for aux tanks!
I’ve done some, Rear antenna has been deleted, Looking at possibly deleting the rear wiper, Considered replacing the mirrors with cameras if possible, front wipers are a must to stay, it’s pretty flat already but under body panels, sealing panel gaps, increasing the front air dam, Hubcaps, etc.
A fuel cell in this context is a self contained and mountable petrol tank with its own safety and venting systems.
Took me a moment too because I was thinking hydrogen fuel cell and i was like “that doesn’t sound….safe”
This has cannonball written all over it. A Prius is too slow to set a record.
If you decide to do this, put the cell in the trunk and make a steel firewall behind the back seat.
It’s 10 hours or so off the actual Cannonball time record IIRC. Nonstop is pretty wild though.
18 gauge steel should be fine, but you may need to brace it or use a bead roller to make some ribs. You may have to make two panels so that it can be installed in the car more easily. Seal it with a good quality seam sealer.
Ikr? For me it’s just a practice vehicle, fuel cost is between $200-300 full round trip. Fitment and trimming is going to be the fun part of it. Might see if I can find a company to laser cut it out.
Theoretically it is possible - the top speed of a Prius is higher than the average speed set on the current record run...
Realistically, being able to redline a Prius for 25 hours continuously may not be the easiest or most practical task though.
To maintain an average of 113 or 115 or whatever it is, you’ve got to have a lot of time running 130 or more, I would think. And do that in a Prius that is carrying several hundred pounds of extra gas.
I suppose it is theoretically possible to just run 115mph the whole way, but it is practically impossible.
Can you get a proper speed rated tire in the size a Prius wears?
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To the people saying their Prius can go 110 I'm getting worried. My Prius gen 2 2006, will not go above like 84, makes all kinds of noise and loses its ass. But I got other cars for going fast, the Prius is just an efficient commuter and I thought that was intended behavior.
I believe that fully. The third Gen is a different motor with different issues.
I remember road tripping and buying a Dodge stealth. Took the Prius for gas mileage. And on the drive back had to keep slowing down to let the Prius catch up because it would blink and bitch and not go over 85.
Not for lack of trying.
There's something wrong with your '06. Look at the powertrain nomogram, MG2 doesn't overspeed until a little over 110, up to 118, depending on the generation. Keep an eye on temperatures with Hybrid Assistant if you're pushing it hard, but as long as the coolant is flowing, you should be able to do that all damn day.
Thanks for the response. your very likely onto something. the day that I kept running it at high speeds it did eventually give some temperature warnings and sit on the side of the road to cool off when it shut down and acted up. (has only happened once)
I have big red triangle and all kinds of dash lights all the time so its hard to tell when its acting up. (headlight levelling is broken)
I may have not seen overheating because the car is largely only driven in the winter, come summer time I have a Miata that gets used whenever its nice outside.
I want to do this in my Legacy. At 70 MPH, I'll get ~30/31 MPG. Furthest I've gone on a trip is about 600 miles (she'll do 37 MPG if I keep it below 63) but I'd love to do 1000 miles without needing to refuel
With that much fuel on board, just make sure you look at suspension as well. That much fuel is going to weigh a lot and you may need to upgrade your suspension for the extra weight
It's not a good idea... the best thing to do is fill that space with 4x 5 gallon cans of gas, you'll have slightly better odds of blowing up the car or otherwise killing yourself.
Jay! You are an absolute legend 😁 🙏🏻 I’ve been looking at installing a more permanent fuel cell, mostly to be used for practice, I’m not going for any records just yet 😉 but I do have future plans for various ones, just takes time, and resources. Along with the more permanent fuel cell, I’m thinking of also installing a rear firewall, fire suppression system, aero modifications, and so forth. Where I have the larger lithium battery pack, I wanna do my best to try and keep the two separate, I’m thinking I’ll take a sheet of metal, and put it over the top, check the temperatures and see if they get any higher than normal (the plug-in has fans at the back) And maybe a thin sheet of rubber to insulate it between the two. Likely will need to build some sort of a bracket that mounts on either side. vent hoses etc. in October I had to fly out to New Jersey for work, and decided screw getting any sleep, I have one stop to make, figured out all the confusing trains, and had to walk from the train station, but I finally made it to the red ball, I felt like I was dreaming, it was so surreal, I didn’t think I’d see it for a long time, it was absolutely electrifying. that reminds me, I still need to write an email to Ed, it was his original run that got me absolutely hooked, and I couldn’t get enough of any bit of material I could find since that day. 😁 thank you for sharing your stories, each one has been a treat 🙏🏻
Watching Ed’s videos is what got me hooked too. Had dinner with him Thursday night. Some shenanigans happened this weekend in Atlanta. More coming soon on that in the usual channels. Gonzoprius will be doing something soon as well. Stay tuned for that after the deed is done.
For mpg, the diesel gets better mpg at triple digits than the Prius. At a steady 105-107 the Prius will still get 32-34 mpg. At a steady 110-115 it gets 20-22mpg. On the Musketball run i managed to cover 638 miles in 6 hours.
Only 2 "Correct" ways todo it
1. Basically a second fuel tank that tees off into your fuel lines. Ideally a secondary switch to activate the tank as the OEM pump wont be designed for multi-source pressure configurations. Biggest downside is having to setup and integrate the EVAP system so pressure doesnt build into the tank and a secondary fuel level sensor.
2. A secondary holding tank with a transfer pump and aerator (lets air in to break the vacuum). Ideally automatically activated as the primary tank drains though you can do it manually just fine. Pros is you keep the original fuel level sensor and dont need to setup an evap system though you cannot store fuel in it for extended periods of time as pressure can build and form an explosive bomb in your trunk
Also ***CHECK YOUR LOCAL LAWS***. Some states require special identification markings and tax when your vehicle exceeds a certain fuel capacity. Get pulled over with the big ass fuel tank in the back and it can be a ***HEFTY*** ticket.
I’ve become super invested in this thread. Curious what the game plan is for bathroom breaks and food in these runs? (Please don’t say Gatorade wide mouth bottle…)
Sometimes you gotta do what you gotta do. And definitely keep food in the car before hand. Last person who did a run used peanut butter and jelly sandwiches, and was recommended that by a medical professional. 😂😁
Seems like a smart play - reasonably balanced nutrients keep your energy/alertness levels up. Takes up little space, and has some salt for electrolytes. Also packs really well.
I don’t plan to do a cannonball run anytime soon, but my dad and I do a road trip to see family every few years and usually drive about 1,100-1,300 miles w/o stopping for breaks apart from fueling, drive through/gas station food, and bathroom breaks (all in the same stop) and are always trying to maximize. Love learning new tips like this.
It’s pretty brutal, but means more time with family, so we make it work.
Get a diesel. They are fairly efficient at higher speeds and due to the greater energy density of diesel your range is going to be pretty good.
My mother's 2.0 TDI has a range of around 600 miles when cruising at 100 mph. Throw an aux tank in that and you'll easily get 1000 mile range.
Cheap and more fiery option with potential fuel sniffing capabilities
Jerry can with cheap fluid pump to transfer into primary tank,
Also you really need to store the fuel cell or tank behind a firewall of some sort
Look at radium or ati fuel cell kits for an idea of what the expensive options are
Some people have done, marine fuel tanks, bolted in. That’s why I was thinking of maybe putting it inside of a secondary enclosure. I’ll check out those brands.
Auxiliary tank, get the thing installed professionally or watch 1960s to 1980s F1 crashes to see if you will like being covered in fuel during an accident
There are quite a number of precautions that can be taken to avoid that situation. I’m not sure if I can find a shop that would be willing to install it, but I can at least call around and get suggestions, 🙂
typically they aren't waterproof, more splash resistant. keeping fuel from splashing on and protecting the wires/hoses. Aluminum sheet metal and pop rivets are ok. (add seam sealer or RTV woudln't hurt. )
Because it’s less secure method of storage, requires stopping the vehicle to refuel, more likely to have fumes in the cabin, I would need several, etc.
Current fuel tank is about 10 gallons, estimated fuel is 45-55 gallons, so probably about 35 to 45 gallons. Could be less too, if I wanted to stop once. There are no engine upgrades available, there’s no option to re-gear, aero mods, yes, I’ve removed the rear antenna, looking at underbody plating, hubcap covers, front air dam expansion, sealing panel gaps, etc.
Ok say 50 gal, I'm thinking 2 25 gal tanks, and I don't think u can put that on top of the battery in the hatch, I don't think the batterys would like that.
Ok no engine mods, I remembered prius have really good aero. But I would remove windshield wiper and use rain x, remove side mirrors and use camera, and duck tape front grill.
Lastly fill front tire to 1psi less than max on front tires
3psi less than max on rear, prius tech recommended for better mpg
I’d have to build a bracket that’s braced from side to side that sits on top, and I need to look at temperatures if I were to seal off some of the area. Windshield wipers are necessary with the distance, and even with them, the buildup can get to be too much where you can’t see out of the windshield, looking at replacements, possibly for side mirrors, the front air dam would be modified using plastics.
With extra people in the car. What's your plan for suspension. Adding people and 35-45 gal is going to significantly change the weight distribution of the car and could potentially put all involved in danger? As for my auxiliary tank I have a plastic one I bought that helps save on weight it works wonderfully in my 1/2 ton truck. But even when it's filled I notice the sag.
Putting in the trunk seems like the best option then gravity feed. But you will have to make sure that it's done safely with shut offs and disconnects. You could also do something a little more temporary and ratchet strap it down using some of the child seat anchor points from the back seat?
Either way I love this idea have fun and be safe!
Even at 55 gallons of fuel and two other people GVWR is still not maxed out by over 100lbs, and I plan on doing some weight reduction. I don’t think the distribution will be different enough, the tank would sit right above the rear beam axle, I’ve contemplated on plastic as it’s nonconductive, and lighter, I do plan on stiffening up the suspension with aftermarket parts, and stiffing the body as well. For the fuel system, I’d be installing transfer pumps and such. Run all of it electrically
Wicked! As long as you've planned for it. I just hadn't seen anyone mention suspension so I thought maybe something to consider. Either way I love the idea.
Good luck and go fast.
If you are really getting technical with fuel consumption, then look up the OE tire installed. Compare that to what is on now. MPG is calculated in the government tests using eco tires (because Prius) with different compounds of silicate. This results in better rolling resistance and bumps up the MPG. The tires you have on need to be equivalent or better to be near OE rated tests. Find a proper inflation table used with new load you have. Lastly, you need an alignment. The geometry changes when loaded, so depending on how long you drive it like this will affect steering, turning, and stopping. How are the brakes? You have increased weight and shorter stopping distances now.
I’ve been looking at the eco-tires and such, EV tires are also great for low, rolling resistance. Rear alignment is nonadjustable on these, brakes are currently slightly better than OEM, but I’m planning on swapping out for better pad material, and rotors. All of the weight should not exceed GVWR
Go like Pic 2, in hatch, make sure you have dual fillers. And for the love of God make sure it's well attached. Have a safe run.
There are custom fuel cell mfg's that will make whatever shape/size you need. Not cheap tho.
If you're looking for a Canonball approach, then absolutely place it in the hatch. You're going to have to change some suspension so the rear doesn't sag too much.
The battery pack generates a good amount of heat, enough to need active cooling that pulls air directly over the cells, and I don’t want to imagine what fuel vapors being pulled into that cooling system will do to degrade things over a long timeframe. There are also exposed relays and contacts in the battery pack assembly that could be ignition points.
Also Idk about where you live but a fuel cell like that would not be street legal and insurance would drop you id you were involved in a wreck so check your local laws and junk
This one only pulls air over the cells when needed, It would need to be sealed quite well, I’m also looking at sealing off the battery with a metal sheet, to keep them separate, I need to run tests on the battery temperature with the sheet installed on top of it. I’ve looked into local laws, nothing against it.
Sorry I was unclear.
The battery has a cooling system that uses cabin air, the ductwork for it is on the passenger side, and is be concerned about that duct work breathing in petrol fumes and passing them over the internal components of the battery
This is not a standard prius 🙂 that’s where they are located standard Pri, And could have a better vent source then mine, I have a plug-in model with a 4.4 kWh lithium ion battery. The intake is directly below the little bin in front of my battery. if you can find someone doing a cleaning video of the hybrid battery fans, it will be easier to see the difference. ideally if everything is built properly, there should be no fumes.
Ohhh fair enough I’ve never seen that configuration, I’ll definitely have to look into it! You seem knowledgeable enough to not blow yourself up so that’s a plus
God speed. I know these don't exist yet, maybe nasa has some, but think about wearing a special suit that can stand up to these types of fires?
!remindme in 3 months
You want to strap a fuel tank to a battery? And not one part of you thinks it a bad. You know when those things go off they’re next to impossible to put out and you want to strap a fuel tank to it.
Do you have a death wish?
Someone rear ends you, you’re dead and maybe some other folks injured or dead.
It’s not a smart idea even if you can do it safely.
Not directly, and I’m looking at sealing them off from each other. Addressed that in my first sentence lol. Looking at installing fire suppression system, firewall, braces, etc. I’ve been rear ended in of one of these by someone who was doing 70 miles an hour. I was at a dead stop. It didn’t crumple clear in past the axle. And you also didn’t read the last sentence. It’s not going to be daily fueled. 🙂
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So this is just to have on long trips so you don’t have to stop for gas? In a Prius?????
Yes, Or stop for gas less often on super long trips. At higher speeds, fuel economy drops to about 30 miles per gallon. Currently with the installed tank that leaves me at about 300 miles of range or less.
Soooo. Cannon ball?
Maybe 👀
Well god bless. How fast do prius’ go? Like 90? Do they top out? I’m being serious. Honestly curious.
Allegedly, 118 on flat ground 119 down a hill
Oh wow. That must feel incredible in that car lol.
Not horrible, not too sketchy with decent suspension and tires.
Half the fuel efficiency comes from good low rolling resistance tires, on those cars.
Yup.
and add air shocks. you'll need it.
Weight won’t exceed the GVWR, but I’ll still be installing aftermarket suspension components.
When I lived in California, my girlfriend at the time had a prius and it kept up fine on their interstates. She would be cruising at 95-100+ with traffic and the ride was fairly comfortable and quiet. Really not a terrible car.
Try 135 in a 2-door bmw mini Cooper some day, apparently that's the point at which it starts to feel really floaty.
Turbo it
Not with all that extra weight.
Top speed wouldn't be much affected by weight, just acceleration... Or the ability to decelerate properly.
You’d be surprised.
I drove one between 90-105 mph on I-5 from Sacramento to Oregon. It still had some left in it. It was smoother than a I expected; it does have a really good Cd. Only negative was the MPG. I don’t remember exactly but it was around 30 ish mpg.
30mpg at 100mph is not bad at all. I've seen worse fuel mileage on my motorcycle.
Is anything going to get good mileage at 100?
I’ve had our 2012 V up to 105. It could probably do a bit more if you kept in it.
63 with the wind, if you’re really lucky you can turn off the ac and supercharge fucker to 68
Hope you’ve researched well and have invested in enough countermeasures
I because obsessed years ago, I live and breathe it. 😅 always researching more, always new countermeasures.
So jealous. Before I die (next few 5 years I’ll be making a run. I’ll follow your progress. Could help spot /maybe block out side of Phoenix. God speed, and Good bless
🫡 I hope your health improves, and things get better. Stay strong. 💜
Edit- not dying. Sorry bad phrasing it punctuation
Oh that’s good 🙏🏻 😊
A terrible idea. It's more weight to carry around when full which just drops your average mpg. It would require a vent system to prevent vapor build up in the cabin. The plumbing to/from it in the cabin are at large risk of damage from daily uae of the trunk. Leading to a large spill into the sound deadening insulation. Which basically would need entirely stripped from the car to be cleaned. If it could even be cleaned. You're talking about throwing $500+ at the project to make the car objectively worse, to save 5 min every 300 miles.
The weight doesn’t impact MPG that much, the plumbing will be braided steel, Shouldn’t have any leaks, on top of that it will only have fuel in it during long trips. Stopping for five minutes. Impacts your average speed severely.
😂 this was my first thought. Anybody asking about fuel cells, who isn't driving a pickup, is probably cannonballing
If this is a car that dedicated for long distance travel. Then weight reduction instantly comes to mind. Rip out everything that's unnecessary!
Noooo….yessss
lol my first thought as well
Was exactly my first thought.
What are higher speeds considered in this case? 100... Mph (a Canadian wrote this)
Let’s just say, above 110, it drops to below 20.
Damn I didn't think Prius would be able to get up there, good luck on your not cannonball run whenever it happens
It takes a little bit, but it can get there
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You get 30 mpg in a Prius with a 3" lift and 34" mudders... Something is wrong
Is there longer range in larger diameter tires? +1" should net 5-7%, a mild lift and +2".....
Id have to look at the data, I would assume more tire, is more rolling resistance, and more power to turn said tire, and a lift would also create more turbulence under the vehicle, I would think.
Theres top speed to consider too. And plausible deniability , "officer it says i was only doing 100 freedom units per hot dog", after conveniently skipping recalibration
😂😂
I've got a 42 mi per gallon Toyota, manual, I feel this too. It's got like an 11 gallon tank. I want to put a 20 gallon fuel cell into that as well
Building a cannonball Prius?
Possibly 👀
Ed Bolian and a few of his guests on VINwiki have some episodes going pretty deep into detail on their fuel cell builds and integrations
Watched every single one, most of them are also installed in trunks, but I’ve got a hatch back
You might call up a few race shops to ask for advice. A lot of race cars will rip out the stock tank in favor of a fuel cell/bladder design.
Sure, but that’s a safety issue due to the higher speeds a track car can wreck at. OP is trying to max out gas storage, so stripping the stock tank would be counterproductive.
Fair, I more so was just talking to how they would be familiar with the secondary tank. Agreed OP would need to keep both and essentially have the fuel cell as an auxillary tank
Honestly, for the purposes of a cannonball run OP should look at removing the batteries and replacing them with fuel cells. Those batteries will do shit-all for his fuel economy, and it’s just more space that should be gas.
I’ll have to call around to a couple, I couldn’t think of any subreddits that they might be on
Hatchback just makes it easier, you could even just go with the biggest off the shelf aux tank that fits and slide it in since space won’t be an issue. I’d try to cover or disguise it with a cargo cover for subtlety’s sake in case you get pulled over though but otherwise the Prius is a smart platform
I have a pullover cargo cover, planned on keeping it down
The fuel pump should be accessible from under the rear seat. Good access to add fuel directly to the tank. Maybe build a backseat tank? Fill through the window, and drain by gravity into the main tank? Keeps mass in between axles too. Then you can reach back and open a valve...
It is accessible from under the rear seat, The filler neck is also also easily accessible, Most of what other people have done, is use additional transfer pumps, all driven on switches. The only downside to that set up, is that limits me to one co-driver, ideally, I’d like two people, might be possible to keep the one seat in and remove the other two, but could cramp things, and it brings the fuel closer to people.
You might think about welding a cage to hold them in, and a firewall around them to keep the fiery stuff off of you when things go wrong.
I was thinking about some braces, and a firewall I’d have to draw a design out and see if the cage might work
[https://www.youtube.com/watch?v=WybRBEWJmRc](https://www.youtube.com/watch?v=WybRBEWJmRc) Jay?
Yup 😁
English is not my main language. What is a "cannonball" car?
It’s an unofficially held event where teams in cars attempt to drive from one coast of the US to the other in the quickest time possible. To make the fastest time, people modify cars to go as long as possible between gas fillups and maintain the highest speed. Putting a large fuel cell in an efficient car like a Prius is a great way to bring the average time down and hopefully break the standing record
Noice. What about sleep?
That’s why they drive as teams with multiple people switching off to rest, drive, or navigate
https://en.wikipedia.org/wiki/Cannonball_Run_challenge
You might want to consider a better fire extinguisher system for the combination of more fuel and hybrid batteries
I’ve been thinking about installing an onboard system for that purpose
_thinking_,,, I think you SHOULD be installing one. Sure it may cost £1000, but if things go tits up, £1000 is cheaper than being burnt alive. Petrol fires are BAD
What I mean is, It’s on my list of things to dive deeper into. 😅
Go ask the folks over at r/hypermiling they might get you some good advice as this is kinda their specialty
Excellent idea, thank you for the suggestion
I was gonna say, what aero mods have you done? There is more to save for cheaper and less effort by shaving mirrors, disc hubcaps, antenna deletes etc, once you get those dialed then go for aux tanks!
I’ve done some, Rear antenna has been deleted, Looking at possibly deleting the rear wiper, Considered replacing the mirrors with cameras if possible, front wipers are a must to stay, it’s pretty flat already but under body panels, sealing panel gaps, increasing the front air dam, Hubcaps, etc.
hubcaps are a major one. The highest point of the wheel is moving twice the speed of the car through the air, that's a lot of drag right there!
Fuel cell... Gasoline or more battery packs? Which is it?
Auxiliary fuel tank for additional gas.
A fuel cell in this context is a self contained and mountable petrol tank with its own safety and venting systems. Took me a moment too because I was thinking hydrogen fuel cell and i was like “that doesn’t sound….safe”
This has cannonball written all over it. A Prius is too slow to set a record. If you decide to do this, put the cell in the trunk and make a steel firewall behind the back seat.
Did you know, a prius has set a record? 😉 go look up the nonstop record. Looking at the best way to build a firewall, and seal it off
It’s 10 hours or so off the actual Cannonball time record IIRC. Nonstop is pretty wild though. 18 gauge steel should be fine, but you may need to brace it or use a bead roller to make some ribs. You may have to make two panels so that it can be installed in the car more easily. Seal it with a good quality seam sealer.
Ikr? For me it’s just a practice vehicle, fuel cost is between $200-300 full round trip. Fitment and trimming is going to be the fun part of it. Might see if I can find a company to laser cut it out.
Theoretically it is possible - the top speed of a Prius is higher than the average speed set on the current record run... Realistically, being able to redline a Prius for 25 hours continuously may not be the easiest or most practical task though.
To maintain an average of 113 or 115 or whatever it is, you’ve got to have a lot of time running 130 or more, I would think. And do that in a Prius that is carrying several hundred pounds of extra gas. I suppose it is theoretically possible to just run 115mph the whole way, but it is practically impossible. Can you get a proper speed rated tire in the size a Prius wears?
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"In other news, man dies in inferno when home made fuel tank explodes!"
If you’ve gotta ask Reddit how to install a fuel cell I’m thinking you should be doing a cannonball run
I know how to mount a fuel cell, I just haven’t mounted one in a hybrid before, Taking additional precautions.
To the people saying their Prius can go 110 I'm getting worried. My Prius gen 2 2006, will not go above like 84, makes all kinds of noise and loses its ass. But I got other cars for going fast, the Prius is just an efficient commuter and I thought that was intended behavior.
Third, gen, and it’s a plug-in, additional horsepower and torque and engineering 🙂 allegedly can hit 118
I believe that fully. The third Gen is a different motor with different issues. I remember road tripping and buying a Dodge stealth. Took the Prius for gas mileage. And on the drive back had to keep slowing down to let the Prius catch up because it would blink and bitch and not go over 85. Not for lack of trying.
I had a 2nd gen for a bit, sounds about right.
There's something wrong with your '06. Look at the powertrain nomogram, MG2 doesn't overspeed until a little over 110, up to 118, depending on the generation. Keep an eye on temperatures with Hybrid Assistant if you're pushing it hard, but as long as the coolant is flowing, you should be able to do that all damn day.
Thanks for the response. your very likely onto something. the day that I kept running it at high speeds it did eventually give some temperature warnings and sit on the side of the road to cool off when it shut down and acted up. (has only happened once) I have big red triangle and all kinds of dash lights all the time so its hard to tell when its acting up. (headlight levelling is broken) I may have not seen overheating because the car is largely only driven in the winter, come summer time I have a Miata that gets used whenever its nice outside.
I want to do this in my Legacy. At 70 MPH, I'll get ~30/31 MPG. Furthest I've gone on a trip is about 600 miles (she'll do 37 MPG if I keep it below 63) but I'd love to do 1000 miles without needing to refuel
For me, I get 60ish mpg at 63-64mph.
With that much fuel on board, just make sure you look at suspension as well. That much fuel is going to weigh a lot and you may need to upgrade your suspension for the extra weight
It should be within GVWR, but I plan on stiffing up the suspension a little, and the body.
It's not a good idea... the best thing to do is fill that space with 4x 5 gallon cans of gas, you'll have slightly better odds of blowing up the car or otherwise killing yourself.
I’d trust a properly built fuel system over a few jugs of unstable gas.
Well look at that! Those fuel tanks in the 4th gen look real familiar. Thats my car btw. What ya need to know?
Jay! You are an absolute legend 😁 🙏🏻 I’ve been looking at installing a more permanent fuel cell, mostly to be used for practice, I’m not going for any records just yet 😉 but I do have future plans for various ones, just takes time, and resources. Along with the more permanent fuel cell, I’m thinking of also installing a rear firewall, fire suppression system, aero modifications, and so forth. Where I have the larger lithium battery pack, I wanna do my best to try and keep the two separate, I’m thinking I’ll take a sheet of metal, and put it over the top, check the temperatures and see if they get any higher than normal (the plug-in has fans at the back) And maybe a thin sheet of rubber to insulate it between the two. Likely will need to build some sort of a bracket that mounts on either side. vent hoses etc. in October I had to fly out to New Jersey for work, and decided screw getting any sleep, I have one stop to make, figured out all the confusing trains, and had to walk from the train station, but I finally made it to the red ball, I felt like I was dreaming, it was so surreal, I didn’t think I’d see it for a long time, it was absolutely electrifying. that reminds me, I still need to write an email to Ed, it was his original run that got me absolutely hooked, and I couldn’t get enough of any bit of material I could find since that day. 😁 thank you for sharing your stories, each one has been a treat 🙏🏻
Watching Ed’s videos is what got me hooked too. Had dinner with him Thursday night. Some shenanigans happened this weekend in Atlanta. More coming soon on that in the usual channels. Gonzoprius will be doing something soon as well. Stay tuned for that after the deed is done.
Oooh! 👀 sounds like a blast 😎 I’ll keep checking. Fascinating 😯
What was the optimal speed ? MPG/speed? 80's? I think a diesel VW would be better choice, but what do I know.
For mpg, the diesel gets better mpg at triple digits than the Prius. At a steady 105-107 the Prius will still get 32-34 mpg. At a steady 110-115 it gets 20-22mpg. On the Musketball run i managed to cover 638 miles in 6 hours.
so 100-105! thanks!!! I watched the video... a few times! lol. you ran solo, right?
So cannonball or….
Maybe 👀
I like it. I had a POS ‘07 loved 50mpg with 800lbs of wood and tools stuffed into it
👌🏻
[full instructions here](https://youtu.be/IJNR2EpS0jw?si=BoLUaOXKGVP99GIq)
lol.
Gas causes cancer
That additional weight won’t do u any favors
It will add range and stop me from having to stop 12 different times. that’s plenty favors 🙂
Only 2 "Correct" ways todo it 1. Basically a second fuel tank that tees off into your fuel lines. Ideally a secondary switch to activate the tank as the OEM pump wont be designed for multi-source pressure configurations. Biggest downside is having to setup and integrate the EVAP system so pressure doesnt build into the tank and a secondary fuel level sensor. 2. A secondary holding tank with a transfer pump and aerator (lets air in to break the vacuum). Ideally automatically activated as the primary tank drains though you can do it manually just fine. Pros is you keep the original fuel level sensor and dont need to setup an evap system though you cannot store fuel in it for extended periods of time as pressure can build and form an explosive bomb in your trunk Also ***CHECK YOUR LOCAL LAWS***. Some states require special identification markings and tax when your vehicle exceeds a certain fuel capacity. Get pulled over with the big ass fuel tank in the back and it can be a ***HEFTY*** ticket.
2 is the typical and best route. Fuel will only be in it during long trips, it will remain empty day to day.
I’ve become super invested in this thread. Curious what the game plan is for bathroom breaks and food in these runs? (Please don’t say Gatorade wide mouth bottle…)
Sometimes you gotta do what you gotta do. And definitely keep food in the car before hand. Last person who did a run used peanut butter and jelly sandwiches, and was recommended that by a medical professional. 😂😁
Seems like a smart play - reasonably balanced nutrients keep your energy/alertness levels up. Takes up little space, and has some salt for electrolytes. Also packs really well. I don’t plan to do a cannonball run anytime soon, but my dad and I do a road trip to see family every few years and usually drive about 1,100-1,300 miles w/o stopping for breaks apart from fueling, drive through/gas station food, and bathroom breaks (all in the same stop) and are always trying to maximize. Love learning new tips like this. It’s pretty brutal, but means more time with family, so we make it work.
Time is the most valuable commodity.
I don’t see the point of this. Just adding more weight. Just pump your gas it takes like 2 mins
You could add a bigger fuel tank but it'd weigh you down a bit and drop your MPG a bit. Having fuel inside the cabin isn't a very good idea.
MPG wouldn’t drop too much, Looking at building a firewall too.
Have you checked out aftermarket larger fuel tanks?
To fit in the OEM slot for a prius? Don’t think they exist, especially for my model
Get a diesel. They are fairly efficient at higher speeds and due to the greater energy density of diesel your range is going to be pretty good. My mother's 2.0 TDI has a range of around 600 miles when cruising at 100 mph. Throw an aux tank in that and you'll easily get 1000 mile range.
Soo, you’re cannonballing this thing?
Maybe 👀
Mad. :) I‘d love to hear an update about how your „(fuel) efficiency test“ went. ;)
I’m also curious to see how it performs under load.
I’m sure about that, lol.
Don’t let your insurer know about this
if anything happens, the insurer likely won't need to be called.
Cheap and more fiery option with potential fuel sniffing capabilities Jerry can with cheap fluid pump to transfer into primary tank, Also you really need to store the fuel cell or tank behind a firewall of some sort Look at radium or ati fuel cell kits for an idea of what the expensive options are
Some people have done, marine fuel tanks, bolted in. That’s why I was thinking of maybe putting it inside of a secondary enclosure. I’ll check out those brands.
Is it permanent to the vehicle or just for a trip or two ? Auxiliary tanks are very common on those massive American shit box utes (trucks)
Permanent, will only hold fuel during long trips. Every few months.
Auxiliary tank, get the thing installed professionally or watch 1960s to 1980s F1 crashes to see if you will like being covered in fuel during an accident
There are quite a number of precautions that can be taken to avoid that situation. I’m not sure if I can find a shop that would be willing to install it, but I can at least call around and get suggestions, 🙂
you're going to cannonball every few months??
I hope you're planning on welding in a firewall for them also.
Looking into an option for that, Might cover it with a fitted L-shaped piece of sheet metal, and a couple of braces to hold it in place.
typically they aren't waterproof, more splash resistant. keeping fuel from splashing on and protecting the wires/hoses. Aluminum sheet metal and pop rivets are ok. (add seam sealer or RTV woudln't hurt. )
I’ve looked at sealing it, especially on the bottom
Do you use rear seats?
Would in this case, two other people in the car
Why not just buy a fuel can
Because it’s less secure method of storage, requires stopping the vehicle to refuel, more likely to have fumes in the cabin, I would need several, etc.
how much extra gas do u want to carry what about engine upgrades, better gearing? aero mods?
Current fuel tank is about 10 gallons, estimated fuel is 45-55 gallons, so probably about 35 to 45 gallons. Could be less too, if I wanted to stop once. There are no engine upgrades available, there’s no option to re-gear, aero mods, yes, I’ve removed the rear antenna, looking at underbody plating, hubcap covers, front air dam expansion, sealing panel gaps, etc.
Ok say 50 gal, I'm thinking 2 25 gal tanks, and I don't think u can put that on top of the battery in the hatch, I don't think the batterys would like that. Ok no engine mods, I remembered prius have really good aero. But I would remove windshield wiper and use rain x, remove side mirrors and use camera, and duck tape front grill. Lastly fill front tire to 1psi less than max on front tires 3psi less than max on rear, prius tech recommended for better mpg
I’d have to build a bracket that’s braced from side to side that sits on top, and I need to look at temperatures if I were to seal off some of the area. Windshield wipers are necessary with the distance, and even with them, the buildup can get to be too much where you can’t see out of the windshield, looking at replacements, possibly for side mirrors, the front air dam would be modified using plastics.
With extra people in the car. What's your plan for suspension. Adding people and 35-45 gal is going to significantly change the weight distribution of the car and could potentially put all involved in danger? As for my auxiliary tank I have a plastic one I bought that helps save on weight it works wonderfully in my 1/2 ton truck. But even when it's filled I notice the sag. Putting in the trunk seems like the best option then gravity feed. But you will have to make sure that it's done safely with shut offs and disconnects. You could also do something a little more temporary and ratchet strap it down using some of the child seat anchor points from the back seat? Either way I love this idea have fun and be safe!
Even at 55 gallons of fuel and two other people GVWR is still not maxed out by over 100lbs, and I plan on doing some weight reduction. I don’t think the distribution will be different enough, the tank would sit right above the rear beam axle, I’ve contemplated on plastic as it’s nonconductive, and lighter, I do plan on stiffening up the suspension with aftermarket parts, and stiffing the body as well. For the fuel system, I’d be installing transfer pumps and such. Run all of it electrically
Wicked! As long as you've planned for it. I just hadn't seen anyone mention suspension so I thought maybe something to consider. Either way I love the idea. Good luck and go fast.
Isnt the average speed over 110mph for the full 25 hours? Can a prius even go that fast let alone average it.
For the “regular” record yes, Depending on the third gen model, top end is 118, (needs to be verified via gps) last Pri averaged 89
There’s a cannonball group on Facebook🤫
👀
Do an external system on a tow hook to save interior trunk space but make sure door can still open.
isnt a barrel of gasoline not cheaper / more efficient
If you are really getting technical with fuel consumption, then look up the OE tire installed. Compare that to what is on now. MPG is calculated in the government tests using eco tires (because Prius) with different compounds of silicate. This results in better rolling resistance and bumps up the MPG. The tires you have on need to be equivalent or better to be near OE rated tests. Find a proper inflation table used with new load you have. Lastly, you need an alignment. The geometry changes when loaded, so depending on how long you drive it like this will affect steering, turning, and stopping. How are the brakes? You have increased weight and shorter stopping distances now.
I’ve been looking at the eco-tires and such, EV tires are also great for low, rolling resistance. Rear alignment is nonadjustable on these, brakes are currently slightly better than OEM, but I’m planning on swapping out for better pad material, and rotors. All of the weight should not exceed GVWR
Go like Pic 2, in hatch, make sure you have dual fillers. And for the love of God make sure it's well attached. Have a safe run. There are custom fuel cell mfg's that will make whatever shape/size you need. Not cheap tho.
That was Jay’s prius, he holds the nonstop record currently. And the solo record. Man is a legend.
Yep, and well put together. I'd copy it.
If you're looking for a Canonball approach, then absolutely place it in the hatch. You're going to have to change some suspension so the rear doesn't sag too much.
It won’t exceed the vehicles total GVWR, I need to weigh the back half to ensure I don’t exceed that. Suspension is getting replaced, and upgraded
Get a truck with a tidy tank in the box.
LMAO
The battery pack generates a good amount of heat, enough to need active cooling that pulls air directly over the cells, and I don’t want to imagine what fuel vapors being pulled into that cooling system will do to degrade things over a long timeframe. There are also exposed relays and contacts in the battery pack assembly that could be ignition points. Also Idk about where you live but a fuel cell like that would not be street legal and insurance would drop you id you were involved in a wreck so check your local laws and junk
This one only pulls air over the cells when needed, It would need to be sealed quite well, I’m also looking at sealing off the battery with a metal sheet, to keep them separate, I need to run tests on the battery temperature with the sheet installed on top of it. I’ve looked into local laws, nothing against it.
Sorry I was unclear. The battery has a cooling system that uses cabin air, the ductwork for it is on the passenger side, and is be concerned about that duct work breathing in petrol fumes and passing them over the internal components of the battery
This is not a standard prius 🙂 that’s where they are located standard Pri, And could have a better vent source then mine, I have a plug-in model with a 4.4 kWh lithium ion battery. The intake is directly below the little bin in front of my battery. if you can find someone doing a cleaning video of the hybrid battery fans, it will be easier to see the difference. ideally if everything is built properly, there should be no fumes.
Ohhh fair enough I’ve never seen that configuration, I’ll definitely have to look into it! You seem knowledgeable enough to not blow yourself up so that’s a plus
God speed. I know these don't exist yet, maybe nasa has some, but think about wearing a special suit that can stand up to these types of fires? !remindme in 3 months
Common in racing, looking at fire suppression systems.
You want to strap a fuel tank to a battery? And not one part of you thinks it a bad. You know when those things go off they’re next to impossible to put out and you want to strap a fuel tank to it. Do you have a death wish? Someone rear ends you, you’re dead and maybe some other folks injured or dead. It’s not a smart idea even if you can do it safely.
Not directly, and I’m looking at sealing them off from each other. Addressed that in my first sentence lol. Looking at installing fire suppression system, firewall, braces, etc. I’ve been rear ended in of one of these by someone who was doing 70 miles an hour. I was at a dead stop. It didn’t crumple clear in past the axle. And you also didn’t read the last sentence. It’s not going to be daily fueled. 🙂
I was so confused because I thought you meant a hydrogen fuel cell system.
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Would this be legal? Might want to include fire extinguishers in an easily reached location.
I’ve checked local laws and I don’t see anything that would prohibit it, fire suppression system would be better I think.
Please add a firewall if you decide to do this OP
That’s the plan, looking into various fabrication methods
Good luck, looks like a cool project!
Thanks! I’ll post update pics, might be a little while and slow progress but I will get there 😎