General Water Methanol Tank Information:
Keep in mind that whatever tank you get, only a percentage of it is usable. The best designs will have an 80% utilization, while the worst maybe 50%. This is due to surging in the tank from accelerating/braking/cornering forces acting on the the fluid in the tank. Pick a tank based upon its design and the usable percentage for your application.
Surging occurs when the tank is less than full whilst accelerating/braking/cornering forces act on the fluid in the tank. Remember, that at 1g of load in any direction, the fluid profile will be at 45 degrees in the tank. So if you have the pickup on the driver side of the tank, and you take a hard left hand turn, you may uncover the pickup when the tank is at a lower capacity. The best way to combat this and gain a greater utilization of tank volume is picking a tank of proper design for the application.
The tank design will dictate how much useable capacity you have. Tall slender designs will allow a greater capacity utilization because surging uncovering the pickup does not occur until lower tank levels. Conversely, low flat tank designs, such as a flat tire well type unit, will have very poor utilization unless designed with a proper sump section.
Once the fluid level gets low, and possibly due to poor tank design, you may have the system suck up some air. Diaphragm type pumps have a more difficult time passing air as opposed to other pump designs. This is made worse by the bypass design pumps. The air can rattle around in these pumps for quite some time and lower pressures and flow rates. If you do uncover the pickup in your tank and get air into the system, consider this a significant problem and address accordingly. Your motor and wallet, will thank you for it.
The fluid pickup location in a tank is important, but there are a few things to consider. Most folks put the pickup at the rear of the tank thinking it will be covered under acceleration. For the most part this is true. But, during hard braking, the pickup will be uncovered, and if you have a fast reacting system, you will suck some air before the pickup is covered again. If you have a proper tank design/system, pickup location is less of a concern because you have minimized surging in the tank.
Baffle Demonstration Video
This video shows the importance of having proper fluid surge control in the tank. One of the major problems that plagues all brands of systems is air getting ingested into the pump by fluid surging in the tank and uncovering the pickup. Once air enters the pump, it may not pass right though, but get stuck in the bypass valves, thus lowering the pressure and flow rate of the system. If the engine is tuned for the injection and a proper failsafe not used, this could cause an issue to the engine.
In most applications our Two Gallon Twin Tank System is baffled as seen in the video.
It is possible to have baffling inserted in other tanks as well. Contact us for more information.
Venting the tank is important for several reasons. First, if the tank is sealed, as the fluid drops, a vacuum will be created in the tank causing pumping issues. Second, if you use a higher concentration of alcohol, you will want to vent this to the outside of the car for safety reasons. Our recommendation is to use the smallest vent to do the job if not using a proper roll-over valve, as this will minimize the capacity for spilling/leaking in a rollover.
Aquamist Specific Items:
Make sure to place the level probe in the proper location, above the tank pickup, to ensure the system shuts off on level alarm before air gets sucked into the system. You will have a much bigger headache on your hands if your engine has problems than having to refill the tank more frequently. Please consult your owner’s manual for how this safety system works with your kit.
Please do not over tighten the tank adapters as this may cause them to leak. Please see “Pickup Location” above for placement guidelines.