air/water in tires

[67temp]

On the old forum I had a thread about adding water in tires. On thing I'm wondering is what psi air would be best to put into the tires. The tires are 33x13.5 on 15x8 non-beadlock steelies and filled with water to the center of the hub. Orginally I ran them at 8-10 psi but since water doesnt compress the same way air does should the air be at more or less psi?

[Happy Bear]

It's early but I'd think you want to run the same pressure you would without water.

[XterraGuy]

Yeah, logic tells me run the same pressure as you would without water. Unless you have the tires completely full of water, they're going to behave the same as far as load support and deformation on obstacles.

[CrawfishStu]

that doesn't sound right for some reason. If you cut the volume of air in half and took up that space with something that doesn't compress, when you go over a rock that would decrease the area inside the tire by say 8-10 cubic inches you now only have half of the original volume of air to take up the difference. Sounds like the tire would be stiffer while deforming if you were running the same psi as before.

[CrawfishStu]

I don't know how much of a difference though.

[doug38s]

this is something I messed a whole lot with when comp crawling. its gonna depend on how much water you put in the tire. I used to run the water all the way to the top of the wheel. I ran no air at all in the tires. they worked very well for crawling.

if I went down to about half. I would go to 4psi.

If I went to the bottom I was around 7-8.

it all depended on what the terrain was and how much uphill and sidehilling we needed to do.

[abtj04]

ok i have to ask....why would you want to run water in your tires?

[frosty]

ok i have to ask....why would you want to run water in your tires?

Extra weight. Especially on a light, rear engined buggy.

[CrawfishStu]

Like frosty said but think about where that weight is. As low as you can possibly get it with out bolting weights to the bottom of the axle.

[67temp]

Extra weight. Especially on a light, rear engined buggy.

You mean we can't do it to a front engine jeep? ;)
My jeep is probably between 25 and 26 hundred pounds before the water.

[frosty]

You mean we can't do it to a front engine jeep? ;)
My jeep is probably between 25 and 26 hundred pounds before the water.

Nope, not allowed. You will be ticketed by the water in tire police.

[Z28YJ]

My jeep is probably between 25 and 26 hundred pounds before the water.

Jebus. I figure my jeep is close to twice that.

[Ripster]

Jebus. I figure my jeep is close to twice that.

Over half of that is in DOM.... :flipoff2:

[abtj04]

OK well that makes sense.... learned something new today