My truck will be getting a turbo soon so I've been looking at wiring my spearco/turbonetics water injection system progressive controller into my maf sensor. What should I use for the 0-5v signal on the maf? I will be doing a draw-thru maf rather than a blow-thru. I know I wouldn't be able to trigger the meth from boost pressure so is there any advice to what else I could do? I'm open for suggestions.
It's a slot style maf FYI and it has a max frequency of 14,500 Hz if this helps. I'll be running a 4" maf tube as well. I've never wired a meth injection system so any help is appreciated.
How come you can't get a meth kit to work off boost?
I have the stock map sensor. They don't have a 2 bar OS for my truck yet that I know of. Forgive my ignorance.Originally Posted by laser_racer
you could run a seperate 2 bar map sensor just for the meth injection. another option is to use an on/off pressure switch, although that brings it on 100% right away.
2005 Cobalt SS Supercharged
60lb injectors, 2.7" pulley, ported blower, dual pass intercooler with option B, cobra heat exchanger, devils own alcohol injection, clear image mid length header, 2 1/2" catless exhaust, zzp intake, powell motorsport "rotated" mounts, hurst shifter, Pedders springs, ss/tc struts, hawk pads and r1 rotors
To make the meth kit read boost you get a kit that has the boost sensor for it. Then you set the meths controller to come on at certain boost with curtain percent meth being sprayed by %. It works like this start spraying meth at 5psi then by 10psi kit is at 100% spray.
Yeah I understand how it works. Could I not use any of the wires from the maf? I'd like to use the maf for this if at all possible. How does the maf determine the frequency at any given rpm or flow rate? Or does this even make sense?
I think using the maf its based of hz instead of boost. I actually put a kit on a hhr ss we had to run a vac line in to the cabin and hook it to the back of the progressive controller. After that is was smooth sailing.
I can't do what you've done with my controller. I'd like to know which wire is used on the maf that determines frequency.
Last edited by emaxxer; 01-29-2012 at 02:09 PM.
Ooooo you already have a kit I thought you were looking for one.
Yeah and from what I've read, controlling the meth via the MAF is much more accurate in the transient fueling events.
For what it's worth the Yellow wire on Pin A is the MAF signal wire and the Black/White wire on Pin B is the ground. Problem is the MAF is frequency based and does not output a 0-5V signal. You will need a maP sensor for pressure reference with a 0-5V signal.
I know nothing about the meth controller you are using so I can't really help much sorry.
I thought frequency was basically the speed at which an electrical pulse is sent from one point to another labeled in Hz. If its anything like a returnless fuel system, the pump would be pulsed a certain speed and when fueling needs increase, the pulse speed quickens essentially speeding up the pump. Excuse me if this sounds whimsicle..... lol
I assume those wires couldn't handle more than 5v before melting so I'll just try the yellow wire and see if the pump speeds up as the rpm of the motor increases. If it runs too soon then I turn the threashold up. Fingers crossed.
If you hook that to the MAF, there will most likely be voltage drop, and the voltage/freq that the computer sees will be skewed. I would not do this, you just asking for it to spit out the wrong data. Do as the others have stated, and buy a 2.5 bar MAP, hook it to a vac/boost source, and let it be the driving force for your meth.
2000 Regal GS ~ 3.25 Pulley ~ Headers ~ 3"ex ~ 1.85 Rockers
Sold 06 TBSS ~ Front Mount T88 ~ 0-30 in 1.17 ~ 0-60 in 3.0
Wanted ~ Engine-less 95/Older 4x4 ~ Jeep/S-10/Ranger for TT Project
How would there be voltage drop if the pump has it's own switched 12v power source? If your theory is correct, the map readings would be skewed as well if you were to utilize the 0-5v signal on a factory 2 bar map equipped engine. And rescaling the maf is really easy on my truck.
Last edited by emaxxer; 01-30-2012 at 10:15 PM.
I thought you where saying you where going to tap into the MAF wire to feed your meth. If thats what your saying, your going to do, then anything tied to that wire will change the resistance, and the value the computer sees. Thats the last thing you want to happen with your airflow. I also didnt say to use the factory MAP. I said get a 2nd MAP like the first person mentioned, and use it stand-alone to drive your meth setup.
An easy way to test if your meth setup will skew your MAF, is to start your car, let it idle while monitoring the scanner. Then connect up the meth system to it. If you airflow readings change, you will then know the resistance created by adding an additional wire/system tied into your MAF will not be a good idea. If it stays the same, then your good. Im guessing just like running any wires, resistance, and ohmage will change, and skew the readings. How far? No idea, you will have to see. But as cheap as an extra MAP sensor is, and as easy as it is to hook a vacuum wire to it, I sure as hell wouldnt mess with my MAF sensor.........
2000 Regal GS ~ 3.25 Pulley ~ Headers ~ 3"ex ~ 1.85 Rockers
Sold 06 TBSS ~ Front Mount T88 ~ 0-30 in 1.17 ~ 0-60 in 3.0
Wanted ~ Engine-less 95/Older 4x4 ~ Jeep/S-10/Ranger for TT Project
Il check it and see if there is any error with it connected to the maf. But worse case scenario, I could just monitor my AFR so I know it's okay. Why does the snow performance kit allow you to use maf frequency or map? Why would the maf be an option on their controller if it wasn't safe?
Just because people sell something doesn't always make it right or wrong.
Yeah but i've read that using the maf is aftually the preferred method over the map that's all.
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