Fuel cell location

[aventino68]

Three options:

1) behind rear axle
2) front of tray above bed
3) 2 cells, under tray outside of chassis rails, ahead of rear axle

C of G wise I’d assume that 3) is best

thoughts?

[Sbeck09]

I can't remember where I read it, but you basically want it as centered as possible. In a truck that usually just behind the cab, but in front of the rear axle. The driveshaft is a limiting factor, but set the cell just above that. This places that mass between the axles and as low (CG) as possible. Check out Frank ZX's F100.

I always had a thought to use 2 cells (1 on each side of the driveshaft under the bed/cab), but can't figure out how you would keep them balanced. Putting them outside of the frame like you suggested with #3 goes against mass centralization.

[Project Bike Truck]

I can't remember where I read it, but you basically want it as centered as possible. In a truck that usually just behind the cab, but in front of the rear axle. The driveshaft is a limiting factor, but set the cell just above that. This places that mass between the axles and as low (CG) as possible. Check out Frank ZX's F100.

I always had a thought to use 2 cells (1 on each side of the driveshaft under the bed/cab), but can't figure out how you would keep them balanced. Putting them outside of the frame like you suggested with #3 goes against mass centralization.

GREAT now I want to move my fuel cell and build a new one. thanks, guys!

[FlyDoc]

in front of the rear axle, on the inside of the frame, would be the best location for CG, and side impact collisions.
in fuel balance you could put in a balance hose, but the drive shaft could pose difficulties, or run them as 2 separate tanks with 2 pumps and 2 gauges, this may be the simplest but haves it CG issues on the track. but depending on HP and total Lbs of the truk, adding fuel to the tanks may have its advantages for CG and balance.

[aventino68]

Ok thanks for that. I need around 30 gallons I think and can't get that between the chassis rails. I could get some, maybe 5 gallons in each tank between the rails and the driveshaft. And the remaining 20 gallons above the chassis rails against the front of the bed in a single custom tank, kind of "n" shaped. but then no room for the exhaust unless I run it outside of chassis rails and that gives me issues of clearance between cab step and frame and rear tyre and exhaust and frame. So probably easiest to just run it in the front of the bed as central as possible. Just like frank ZXs F100.

[drummerdad]

I have been thinking about this also. Im thinking of making my own aluminum tank, around 15-20 gallons Im guessing. So, full it would weigh around 120 lbs. If I move the battery, and the exhaust to the opposite side of the tank, I can offset the weight a little. Not the full 120+ lbs, but Im not as concerned about CG, as I am the truck leaning to the left while my fat butt is in it.

The opposing tanks with a balance tube sounds good, but like has been said the driveshaft might impede on the idea. Aviation uses this system to great effect. Multiple tanks, feed through gravity or transfer pump to a feed tank. Engines pull from the feed tank, but the pilot can adjust the CG by moving fuel from the fwd and aft tanks (in helicopters, fixed wings might also have wing tanks) when necessary. They also have sumps that weigh the fuel, so they know how much to move. Somewhat more complicated than you would want, Im sure.