Brahma On-Board Air

[Rezarf]

I just have to add this: I don't know why it takes me so long to do stuff like this - I looked over Marco's thread and he installed his in an afternoon. Mine took me two weeks +/-

Oh well. It's just the way I am I guess.

Your a race car compared to me!

...wait, I have two kids under 3, yeah that's it!

 

[corsair23]

Not pretty but if it works...

 

[subzali]

Not pretty but if it works...

We'll call this...testing the theory...yeah.

 

[subzali]

Another data point. From today's run.

1000 rpm, 1:30 to fill from 12 psi to 36 psi. Not bad, and a lot better than my initial test run. Maybe adding oil is helping the compressor efficiency a little bit

 

[subzali]

When the car tire is flat in the driveway, I'm thankful for my On Board Air. That is all.



no, I haven't invested in a garage air compressor yet

 

[rockrod]

Do you have a storage tank? It really improves the air up performance.

Nice work!

 

[nakman]

Do you have a storage tank? It really improves the air up performance.

Nice work!

I think storage tanks help on the first tire, but after that they're less of a help, possibly even an impediment. When I ran OBA my tank pressure would be a solid 90psi, yet after the first tire would drop to around 45 (while filling) and pretty much camp out there, along with the rest of the system. So then to get air into the rest of the tires you're not only filling the lines in the system, but a larger tank, which at that point is almost in the way. There's obviously some recovery benefit between tires though. To really prove this out you'd want to measure PSI at the compressor and in the tank, record readings before you start, during each tire, etc. And if you put a shut-off valve to & from the tank so you could easily disable it, time yourself on all 4 tires both with the tank and without. I'd be interested to see if in fact it's actually a little faster with no tank.

 

[rover67]

Nak, I disagree....

Without one the compressor cycles a lot. It'll shut off in between tires, not be running while you are hooking up air hoses, not filling a tank while you are heading to the air up spot, and not holding air afterwards.

Using one gives a nice buffer and gives a huge head start when you pull into the air up spot. also, when you are chatting while switching from one tire to another, it is filling.

 

[subzali]

I don't have one. My puny 31s don't take long to fill.

 

[nakman]

Nak, I disagree....

Without one the compressor cycles a lot. It'll shut off in between tires, not be running while you are hooking up air hoses, not filling a tank while you are heading to the air up spot, and not holding air afterwards.

Using one gives a nice buffer and gives a huge head start when you pull into the air up spot. also, when you are chatting while switching from one tire to another, it is filling.

Yes you gain a little between tires, particularly when chatting excessively. But once your tank pressure drops the pump cycles on and doesn't shut off until you stop filling- at least that was my experience.

Imagine two guys filling up truck tires with a bike pump. One of them puts a storage tank between the pump and the tire, the other goes direct- you give tank guy a head start to fill the tank until it equals the output pressure of the pump, then start a race. I say the guy without the tank wins, and there's an inefficiency to pressurizing the greater volume of air inside the tank.

Kinda like a 4" water line in your house- your water pressure would taper off pretty quick, right?