Isuzu npr 4wd

[gator70]

Hello Gator70:
Are you planning to fill two 37" tires off of compressed air stored in the two reservoir tanks without a compressor? I might have misunderstood your post asking if a three liter tank and 150 psi would fill two tires. I assumed you were looking at a small compressor with a 3 liter tank that produced 150 psi maximum pressure at an unknown CFM rate. If that is not the case ands there will be no compressor adding air to the two tanks as you fill the tires it is unlikely that you'll be able to add a significant amount of air. The volume of a 37 x 12" tire depends upon the wheel diameter, but is most likely greater than 20 gallons assuming a 17" rim and a 12" wide tire. If your two reservoirs had around 1 gallon each (based on your posted question) at 150 lbs psi and you connected those tanks to two tires at 0 psi (after repairing a flat) the total volume of tanks and reservoirs would be around 42 gallons. Boyles Gas Law proposes that pressure and volume are inversely related (we'll ignore temperature to keep this simple). So you've increased the volume around 20 times so you'll decrease the pressure 20 times. 150 / 20 = 7.5 psi. Better than 0. but not much pressure to drive on at any speed above a crawl.

Someone much better at math and physics than me could figure out how much increase in pressure you could get from the reservoirs into the tires at various pressures, but I doubt it will be enough to help you out after airing down your tires any significant amount. Most systems that fill tires from stored gasses go to CO2 or others that can be compressed to liquid states and thus yield effective volumes when released into your tires. Power Tanks are a good example.

Howard Snell

Yes it was misunderstood. There is a compressor with two tanks. Tanks total are 4 gallons.

 

[gator70]

My calculation is each tire needs 5.8 cubic feet of air to fill half way

 

[gator70]

As the subframe moves, does the rear fenders move too? Are they attached to the frame or the subframe?

 

[SkiFreak]

On my truck the rear mudguards are attached to brackets on the chassis, but the reality is that it does not really matter one way or the other.
Mudguards are normally flexible, so are not usually affected if twisted, unlike a camper body.
It probably comes down to what the regulations are in your state.

 

[gator70]

On my truck the rear mudguards are attached to brackets on the chassis, but the reality is that it does not really matter one way or the other.
Mudguards are normally flexible, so are not usually affected if twisted, unlike a camper body.
It probably comes down to what the regulations are in your state.

Maybe you speak of what we call Mudflaps. I'm talking about aluminum fenders

 

[SkiFreak]

Mudguards/Fenders... same thing.
As I said, they will flex, so it does not matter if you fit them off the chassis or subframe.
If you are concerned about their flexing having a negative affect, just mount them off the subframe.

 

[gator70]

My habitat comes with a basic lithium battery monitor the lcd type. Is it easy to swap it out for a better one? And is it only the shunt?

Any suggestions on a upgrade?

Due to the 12v air conditioner and the 600amp hour battery bank. I can assume the batteries will only power the A/C for 8 hours after dark.

Since I have a 12v fridge/freezer combo, it needs power after the A/C depletes the batteries, predicted to be at 3-4 am.

So, I will set up a separate system with a 100amp hr battery for this 12v fridge/freezer combo appliance. So it runs independent.

 

[Ferjablito]

Tal vez hables de lo que llamamos guardabarros. Me refiero a los guardabarros de aluminio.

Maybe you speak of what we call Mudflaps. I'm talking about aluminum fenders

to the box if you have a free torsion chassis

 

[Ultimark]

Maybe you speak of what we call Mudflaps. I'm talking about aluminum fenders

In Australia we have mudguards, which is the aluminium bit in this picture, then attached to the rear of the mudguard we have a mud flap, which can be seen on the rear hanging down.

Mick.

 

[gator70]

When making decisions on this entire build, the super singles played a big role. Originally I was going to use a divorce transfer case and two 2004 f450 axles. Then purchase a set of 5 Stazworks 20x10 wheels.

Later the economics and long term sustainability pushed me in the direction of Ridgerock.

Here the super singles are 20x9 and 67% less in cost.

The front axle is now a super duty (newer), and the rear axle OEM Isuzu.

Everything is new or replaced, warranty was a big deal.

And no ecm codes will be present, as everything is compatible.

Steel super singles shown below

 

[gator70]

Fuso FG builds in the USA with complete habitats are running $160--$200K. Turn key.

(this is the newer series - not the older ones - not big enough for a family only a couple)

I am interested in opinions why?

 

[gator70]

How do you value a well built composite habitat? Most DIY models have less value and tend to be designed based on one person's vision.

If you list all parts that are part of a well built composite habitat in a spreadsheet. The list is a mile long. And the cost of the parts easily can add up to more than the truck platform.

Who has a take on this?

 

[DzlToy]

Don't add up the money you spent; you will cry. Building a custom car, truck, rock crawling buggy, mountain bike or fishing boat makes absolutely no sense, fiscally.

That said, if you want your work and investment protected, you would be well served to find someone willing to give you a stated value policy. These policies are typically written for high value collector cars and the like. So, if you are going to be travelling the country and racking up the miles, these two themes may run counter to one another.

 

[gator70]

Don't add up the money you spent; you will cry. Building a custom car, truck, rock crawling buggy, mountain bike or fishing boat makes absolutely no sense, fiscally.

That said, if you want your work and investment protected, you would be well served to find someone willing to give you a stated value policy. These policies are typically written for high value collector cars and the like. So, if you are going to be travelling the country and racking up the miles, these two themes may run counter to one another.

This applies to most projects.

A high end expedition vehicle is in a whole different category.

Most with investments in excess of $200K USD

 

[gator70]

Still trying to spec my air compressors - investigating cubic feet of air

+++++++++++++++++++++++++++++++++++++++++++

To calculate the cubic feet of air a tire can hold, we need to make certain assumptions about the tire's overall dimensions and the shape of the air-filled space inside it. Here's a simplified approach based on the tire dimensions:

Assumptions:

• Tire size: 20x12.5 (which typically means 20 inches in diameter and 12.5 inches wide).
• Rim width: 9.5 inches wide.
• The inner air volume of the tire is approximately cylindrical.

Steps to Estimate Volume:

1. Convert tire dimensions to feet:
   • Diameter: 20 inches = 20/12 = 1.67 feet.
   • Width: 12.5 inches = 12.5/12 = 1.04 feet.
2. Assume the rim subtracts from the internal volume: The rim (9.5 inches wide) takes up space inside the tire. We'll assume the tire itself has a cross-sectional thickness and that the inner diameter is less than 20 inches due to the rim.

Let's assume the average diameter for the air space inside the tire is 18 inches (1.5 feet). This is a rough estimate that accounts for the space taken up by the rim and tire walls.

1. Calculate the air volume inside the tire: The formula for the volume of a cylinder is:

V=πr2hV = \pi r^2 hV=πr2h

Where:

• rrr is the radius of the tire’s inner air-filled area (1.5 feet / 2 = 0.75 feet).
• hhh is the tire's width (1.04 feet).

So, for this tire:

V=π×(0.75)2×1.04V = \pi \times (0.75)^2 \times 1.04V=π×(0.75)2×1.04 V≈3.14×0.5625×1.04V \approx 3.14 \times 0.5625 \times 1.04V≈3.14×0.5625×1.04 V≈1.84 cubic feetV \approx 1.84 \text{ cubic feet}V≈1.84 cubic feet

Thus, the estimated volume of air the tire can hold is approximately 1.84 cubic feet. This is a rough estimate, and the actual volume may vary depending on the tire’s exact shape and internal structure.