Seishuku wrote:Won't that injector rust solid after a few days?Spray mixes usually contain water and meth, both of which contain oxygen, and will rust parts pretty quick.
Also, those pumps don't push much, if any pressure at all, so it's mostly useless under boost.
The injector is a good idea though, if it can deal with the fluid.
The injector might rust, but a solution is to use a small squirt of Marvel Mystery Oil in the the resovoir itself. This will lube the pump and the injector. Or by adding a small amount of radiator anti-rust to each tank, having the same result.
The pump only has to put out 10-15 psi more then the amount of desired boost pressure in order for it to be very effective. Personally I would use any RV water pump I could get my hands on. Since the pressure we're working with is very minimal, almost any RV pump will work very well since even the small / older ones provide more then enough flow for a small nozzle to mist correctly.
The hobbs switches come adjustable, so you can tune the pump "on" time by adjusting the Hobbs switch itself. As far as tuning for flow, you can add a rheostat to regulate pump voltage or use a nitrous nozzle and tune the jet sizing according to your needs.
The idea here is to keep it cheap and easy. This is about as basic as you can get. From here you can do almost anything you want, to include adding various methods for controlling flow, adding stages, even adding a variable flow controller so the water/meth spray is ramped up as boost pressure increases.
The CSI can also be used with the Hobbs switch as a way to add fuel. Just "T" into the fuel line on the pressure side and run the fuel line to the CSI. It will now add fuel instead of water whenever the Hobbs switch tells it to. Another great way to add a few psi of boost without upgrading your entire fuel system.
People have been doing this for 15 years with great success.
Josh, I made some minor editing changes to your original post just to clean it up a little. I also changed one of the pics that started showing up as a Red X.
WD