so your saying a such thing exists as a "variable resistor"? I will check into it. Now... all I remember from ECE is V=IR.... so how does hooking up a resistor to a voltage reduce the voltage?

My idea thus far:
-route the sensor output to a switch.
-route a line from a const. voltage source (like the batt. terminal) to an adjustable
resistor.
-route the line from the resistor to the switch
-route the output of the switch to the ecu.

this way I know that the input voltage is constant, therefore the selected resistance should be correct. But does resistance work that way? I thought putting a resistor in the line just reduces current flow....

 

I think to simplify things, I just draw a circuit so it is clearer.
( I think the circuit below describes exactly what you are trying to do):





After the engine is warmed up, switch over to the variable resistor and trim it until the voltage reads the same as the table posted for a given engine temperature.

I think the variable resistor should be at least 1W power rating.

Richard

 

wow, you're more than awsome.
now, once I dial this resistance in, it should remain constant correct? so say I'm shooting to read .55 Volts, I just do as you said and trim the resistor to xx.xx ohms to get an output of .55 volts and then I never have to mess with it again?

(any equation for me to figure out what the range of this variable resistor should be? ....does it need a max. rating of 500 ohms? ...1000ohms?)

(I haven't looked for this sensor wire yet.... it's gonna be just like that diagram right? meaning there will be only 1 wire comming from the sensor?)

 

The variable resistor should remain stable - if you go a multi-turn trimming resistor, it is much easier to keep the resistance stable. Ensure the rating is at least 1 watt.

 

I'll look into that ...hmm... a multi-turn trimming resistor..... google.

 

I have received quite a few email enquiries from the evo community recently regarding "how to interface with our water injection system". I may not know all the EMS available for the EVO but I can work them out individually if I was given time and some information for you.

First of all, if you can post a list of EMS here, standalones or piggyback. I will do some research and do my best to create a few wiring diagrams to interface with them.

Richard

 

Richard, which route will produce better results for 100% water injection

1) 12.5afr, 20psi, more timing OR

2) 12.5afr, 24psi, less timing?

Or something other than the 2 cases above?

 

i really hope 24 psi, less timing, cuz that's me. ('cept I cant reach anywhere near 12.5, I'm @ about 11.4)

 

How much water (volume % ) to fuel are you injecting................?

 

Here are a few off the top of my head that I can think of:

AEM EMS 1313/1313U (standalone) http://forum.aempower.com/bbs/login.php
Autronic (standalone)
UTEC (piggyback)
ChipTorque/Vishnu Xede (piggyback)

Let me know if you have any questions about the AEM EMS. I'm in the middle of interfacing with mine right now.

 

roughly 15%

 

u running the FiA2/HSV?

 

if you're asking me, I don't even know what that is, so no.

 

Richard...have u abandoned evom?

 

It has been quite a hectic past week for me and will continue for the next week as well. I could not spend as much time as I like on the forum - I am not abandoning it.

Your question regarding the boost pressure:

I would run more timing at 20 psi than 24psi with less timing generally. But if your turbo's efficiency map can allow you to run at 24psi without blowing a great deal of hot air into your engine, than by all means run 24 psi. You will probably find you will only need to dial minimal amount timing to sustain the 24psi boost.

"Pre-turbo" water injection may be your answer, it is exactly what I am doing now - doing some development on this subject. Follow by a local drag racing venue on the coming Saturday.

You can see the progress of the project here.


Can you post your turbo efficiency map here?