Boatbuilder79
Well-known member
Sure would be cool.
How come nobody makes one for the masses?
Or is there a kit I just don’t know about?
How come nobody makes one for the masses?
Or is there a kit I just don’t know about?
Central tire inflation system
- Thread starter Boatbuilder79
- Start date
luthj
Engineer In Residence
They have distinct downsides. You might read through a big truck forum to see.
Typically this requires a modified hub with air line from the body. These can catch and tear on just about anything.
The other style requires the axle to be specifically designed to accommodate the air line, with a extra set of hub seals and a rotating collar to connect the wheels air line to the axle.
Typically this requires a modified hub with air line from the body. These can catch and tear on just about anything.
The other style requires the axle to be specifically designed to accommodate the air line, with a extra set of hub seals and a rotating collar to connect the wheels air line to the axle.
Boatbuilder79
Well-known member
No doubt it would not be cheap
but would be bas ass.
but would be bas ass.
luthj
Engineer In Residence
Its a cool idea, and makes a decent amount of sense on big trucks where copious high pressure air is already available. But installing such a system on a smaller vehicle would add significant unsprung weight to the axles, and introduce new failure points. Multiple seals that could fail and deflate a tire, numerous valves which can seize up, or freeze if water gets into the system.
If you go the external route, there is a line on the outside of the wheels which will rip clean off if caught on a branch or rock, could get pinched against the wheel, or even just damaged by spinning through deep sand.
Its kinda like put 40" tires on your rig. It may look cool, but unless you have a rig that demands it, you are going to regret the trade offs.
If you go the external route, there is a line on the outside of the wheels which will rip clean off if caught on a branch or rock, could get pinched against the wheel, or even just damaged by spinning through deep sand.
Its kinda like put 40" tires on your rig. It may look cool, but unless you have a rig that demands it, you are going to regret the trade offs.
Metcalf
Expedition Leader
Dana Spicer had a prototype kit at EJS like 2-3 years ago that just bolted right into a Jeep JK.
It seemed to work just fine and was minimally obtrusive as far as mods.
Metcalf
Expedition Leader
Generally, that isn't how most CTIS systems work now. Ripping a line off doesn't cause you to lose air pressure in the tire. That would be dangerous.
I think it was Syegon, a french company, that had one of the first patents for the modern CTIS wheel valve. Basically, you add air pressure through the valve, but you apply vacuum to the same feed line to 'open' the valve at the wheel. This dumps the air in the tire much faster since the air doesn't have to travel through the small feed line to the control box.
A lot of the systems are not based on light nylon air line. That stuff sees millions of miles in the commercial world. It is available just about anywhere. The fittings are common and easy to replace. Weight is almost nothing really. If you already have a compressor on your vehicle to air up the tires anyways, the added weight looks minimal.
It is a more complex system, but they have most of the dangerous stuff engineered out. Worst case these days, the system just doesn't air the tire up or down. That isn't really the end of the world, it is comparable to having the lockers not work.....which can happen with an air driven locker too.
luthj
Engineer In Residence
I vaguely remember seeing some photos. Looks like a custom axle. There is no technical reason it couldn't be integrated by the OEM, but it would be a bit expensive unless you were already doing axle swaps.
Metcalf
Expedition Leader
Yup, but the air line outside the vehicle is the most basic way to do things.
Boatbuilder79
Well-known member
I think ford needs to develop a system for the raptor.
Joe917
Explorer
When I bought our Mercedes 917AF, it came with an external CTIS system from Brazil. The company that made it would not provide any technical help. It was a fixed 130 psi (fine for the hwy trucks) and required a wrench to air down. After I ripped the supply lines off driving in the bush that was the end of it. More trouble than it was worth. Now the CTIS on a Unimog...
Boatbuilder79
Well-known member
it seems like that would sell. I wonder why it isn’t in production.
Metcalf
Expedition Leader
If I run into them again at EJS I will ask them.
With how much I fight with the newer vehicle crowd on the trail about airing down, I don't think it would sell well at this point. I constantly ask people on the trail if they are aired down when they are having issue. I get a lot of 'yes, I aired down to 20psi' responses. I also watch them flounder compared to other vehicles that have aired down more aggressively on the same terrain.