5 gallon is quite a bit, you'll need a big air hose pressurizen the tank if there is lets say only half a gallot left, it take 4.5 gallon of air to pressureize to make the water pressure at the nozzle equal to the boost pressure.

I run an fc with 6l trunk mounted tank and 8mm air tube. works really well

 

Our kits come sanded with 8mm hose right off the shelf.

 

yes, but 5 gallot is alot.. would be a good test with lets say 1 gallon in the 5 gallon tank to connect a 5 bar sensor right at the solenoid or nozzle and then connect it to datalogit and see the pressure response of the water a load/boost step.

 

Yeah I would think with a 5 gallon tank you would want something like 1/2 or larger. Not an issue when its full, but when its close to empy that's a lot of space to fill, not to mention air compresses more than liquid.

Some of the guys running the Wannaspeed.com kit with the larger 2.5 gallon tank in the trunk run larger lines and/or a check valve to keep pressure up between shifts. Then it only has to fill once. The drawback is you lose your variable water flow at lower boost levels.

 

we found in testing when desighing our tanks, It is possible to run large tanks but they must be designed with mechanical water injection in mind. If you use a normal generic vessel, you will have a richer water ratio when the tank is full, this is because you have the increase weight of water and the pressure from the turbo acting on the nozzle which increase water output some what.

You can obtain custom tanks and have then made through our website
mechanical-water-injection.com

 

We are wondering how you get a large tank that's almost empty to have good response? Unless you can build a tank that can change it's size based on the amount of liquid inside, I don't see any way around the issue. Regardless of the type or design of tank used.

When the tank is full the remaining space to fill is very small. When it's almost empty that half quart of space is suddenly 4 gallons. Different materials and dimensions won't change that.... It's like filling a jar with a water hose and then a bathtub with the same hose. Unless the size of the water hose is changed, the bathtub will always take longer to fill.

 

There are ways round this, which you will find out by looking around and doing some testing and research for your self with your own kits. Im not in a position right now where i can disclose this information, i hope you understand and don't take offense to this.

 

Very interested in buying this kit Erdin! I replied to your group buy thread on fduk a while back but it came to nothing.
Are these still available?

 

Bringin an somewhat old thread to life, does anyone know what sice CC / aka volume the nozzles in these setups delivred ?

typ 500cc / 750cc / 1000cc ( yes i know water amount was somewhat adjustable with a needle & seat valve )

thanks for any inputs

i have tried contacting the vendor but seems to have closed the buisness.

 

As a guide at 20psi it will flow 500cc
at 29psi around 1000cc

I was not getting much interests in these kits, so saw no need to keep the site open. If you want to buy one pm and i will fix you up

 

Hello Erdin and thanks for the info, im running the kit at this moment and have meassured the volume at different pressures / valve settings, but since there was no nozzle specs in "kit-manuals" i thought it would be interesting to see if others had same results, as it was difficult to see if the air-atomizer is modified in som way. I have been running this pre turbo setup for 4500miles this season, @21 psi and it delivres about 500cc / minute.

 

Sounds like its bang on the money

 

original link is dead .. anybody have a new one?

 

Wannaspeed carries one as well....

Mechanical Pre-Turbo Water Injection - Wannaspeed

 

PM 'Erdin' in this thread to get a qoute...


J.

 

If anyone is interested in running a larger volume tank system without the intake volume compromise you could easily do this by running only a 0.5L active pressure tank with a gravity feed and 1 way valve from your main water tank, which could then sit at atmospheric pressure. This means the main tank can be a much simpler/cheaper item as it doesn't have to deal with boost. Might look a buying one of these kits myself. Would like to know specs on level sensors mentioned earlier too, looks like a "ground loop" type of deal? I starting looking through catalogs and things for a decent level sensor to go into a pressurised tank and what I found didn't look anywhere near as sturdy as the one in this thread.

 

Is there some kind of lifting diaphragm/sprung seat magic in the modified spray body to get a 100% flow increase with ~%50 pressure increase, I would have expected closer to ~650cc flow at ~30psi from a 500cc nominal at 20psi spray setup based on all the OEM air atomiser charts I have looked at, they generally trend in a logarithmic/fractional power flow increase with driving pressure, the above would be the reverse?