Faster Refueling for Lemons Racing
#21
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Well I'm glad I listened to you guys. It really came down to the dump can and some operator error. The OD on our dump cans was too big and was blocking the filler neck vent. We shifted the nozzle to the side and dumped 5 gallons in 15-20 seconds. So those expensive fittings are getting sent back. Thanks for all the help guys!
#22
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Hey guys, I was hoping for a little help on something else related to the fuel tank. I read an article on Grass Roots Motorsports a few months ago about how they modified the "in tank vent tube" to allow for more fuel in the tank. Basically where the vent line is located in the fuel tank is rather low, they put some pipe fittings on the tube and moved the termination of the vent closer to the top of the tank so that all the air could vent during refueling. There by guaranteeing that you get approximately 14 gallons of fuel in the tank. My thought is to just slip a 10-12" piece of fuel hose onto the line and aim it up at the highest point in the tank.
So two question, is this a really bad idea? I can't foresee it causing any leaking issues. And does anyone know the diameter of that pipe in the tank. I thought it was about 5/8" but not totally sure....
So two question, is this a really bad idea? I can't foresee it causing any leaking issues. And does anyone know the diameter of that pipe in the tank. I thought it was about 5/8" but not totally sure....
#23
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Two things to consider; two very big things:
1. What happens when people notice that you can easily go 2 hours per stint while driving faster if your previous stints were fuel limited to 1h40m?
2. What happens when your vent tube starts siphoning gas from the tank because you're now filling the tank all the way to the brim?
1. What happens when people notice that you can easily go 2 hours per stint while driving faster if your previous stints were fuel limited to 1h40m?
2. What happens when your vent tube starts siphoning gas from the tank because you're now filling the tank all the way to the brim?
#24
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Two things to consider; two very big things:
1. What happens when people notice that you can easily go 2 hours per stint while driving faster if your previous stints were fuel limited to 1h40m?
2. What happens when your vent tube starts siphoning gas from the tank because you're now filling the tank all the way to the brim?
1. What happens when people notice that you can easily go 2 hours per stint while driving faster if your previous stints were fuel limited to 1h40m?
2. What happens when your vent tube starts siphoning gas from the tank because you're now filling the tank all the way to the brim?
2. Isn't that an open line inside of a closed system. The vent line inside of the tank does not vent to the atmosphere, it starts in the tank exits to a hose that runs to a bull head in the filler neck. I guess if there is zero air in the tank you could be creating a vacuum but that would already be the case with the current system right? The gas cap is a one way valve correct? When you consume fuel air goes in and when you roll over (God forbid) the cap keeps the fuel in.
#25
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Two things to consider; two very big things:
1. What happens when people notice that you can easily go 2 hours per stint while driving faster if your previous stints were fuel limited to 1h40m?
2. What happens when your vent tube starts siphoning gas from the tank because you're now filling the tank all the way to the brim?
1. What happens when people notice that you can easily go 2 hours per stint while driving faster if your previous stints were fuel limited to 1h40m?
2. What happens when your vent tube starts siphoning gas from the tank because you're now filling the tank all the way to the brim?
#29
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If you switch to a 1.6, you shouldn't have a problem getting close to 3hr. To make up for not having any torque, swap the rear gears from a Kia Sportage. I'm guessing you are running 4.10 gears? The shortage front gears get you 4.778 changes the way it accelerates dramatically.
#30
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I don't buy it. Doing a 1.5 hour strategy depends largely on the format (Double 7 vs a Single 12, etc) and how good your pit stops are in general. It's completely possible to get a new driver into the car quickly, but the theory doesn't hold up with 3 minute driver changes.
If your driver changes are 2 minutes on the dot, for a 7 hour race, you'll save a minute. For a 12 hour, looking at 2 minutes.
If your driver changes are 2 minutes on the dot, for a 7 hour race, you'll save a minute. For a 12 hour, looking at 2 minutes.
#32
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I don't buy it. Doing a 1.5 hour strategy depends largely on the format (Double 7 vs a Single 12, etc) and how good your pit stops are in general. It's completely possible to get a new driver into the car quickly, but the theory doesn't hold up with 3 minute driver changes.
If your driver changes are 2 minutes on the dot, for a 7 hour race, you'll save a minute. For a 12 hour, looking at 2 minutes.
If your driver changes are 2 minutes on the dot, for a 7 hour race, you'll save a minute. For a 12 hour, looking at 2 minutes.
Now, if you can drive 3+ hours on fuel, you still have to make 3 drivers changes, and fuel at least two times. You could stop at 2 hrs, 4hrs, and 5.5hrs. Hours 2 and 4, you take fuel (5 mins each, 10 mins total). On the 5.5hr stop you only have to change the driver (3 mins). Now you've only spent 13 mins in the pits. So you've gained at least 1 one lap on the rest of the field.
We can do a driver change and fuel in about 3 minutes. We've lost races by less than one lap. So that one lap gained could have won us a few races.
#34
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This is apparently a very common modification for endurance. How exactly have folks plumbed this vent into the top of the tank? I've seen an AN fitting into the lid suggested, but clearance of the cover is apparently an issue. Would appreciate a suggestion from someone who has done it before stumbling around with this. Thx
#35
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Reach in and bend it up. We did a 1.6 to 1.8 tank swap before we realized that’s all they really did. Bent the 1.8 vent up and gained a bit more, fuel cell ftw. Fwiw, the design of the 1.6 vent looked difficult to bend vs. the 1.8.
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