PDA

View Full Version : Control of EFIE, PWM, & MAP/MAF sensors through a small computer



dennyk159
07-24-2008, 10:25 AM
Not to be confused with the ECU...

Hydroxy Technologies sells what they call a VMU (Vehicle Management Unit, http://www.hydroxycorp.com/shop/item.asp?itemid=33), & not to try to cut in to their sales or anything($439), I'd like to try to build one. They have Youtube videos as well (search vmu hho). It appears to me they have a small CPU with a touchscreen controlling an interface box that would more than likely be mounted somewhere under the hood. It has MAP/MAF sensor control, PWM, & O2 parameters. As of now, they are the only thing like it I've seen.

I'd like mine to do all that plus take input from the vehicle's OBD, & be able to display those parameters. I think the VMU can even turn the HHO generator on & off. That's not as important to me as being able to see how things like how the O2 sensor readings change from HHO off to HHO on. You could even use those readings to write algorithms to adjust them as needed.

One other thing I thought could be controlled would be a PWM being adjusted for such things as amps & temperature, since these two essentially define HHO output. You could have the amps increased while cold, then back off as the unit heats up, for example.

Now, I do have some electronics background, but it's been 25 years since I have even remotely been involved with it. Except for building around 5 home computers over the last 10-12 years. I think the interface box would need a PWM, EFIE, & other sensor inputs, with A/D & D/A so the controller could receive & output data. The question is, can you use some of the designs currently offered on the net, just modified slightly where the variable pots make the changes with D/A converters?

I have been looking into the the possibility of using a GPS unit as the CPU control box. They are all pretty much just little computers, I'd just have to be able to connect the interface(s) to it. In researching GPS's aftermarket programability, the Tomtoms (or at least some) have open source programming. (http://www.opentom.org/Main_Page) And, having the GPS inputs readily available, more accurate MPG calcs may be a reality.

I'd be interested in hearing what anybody here thinks about this. I may need programming/interface advice, for anyone who is a tinkerer like me) I may be in way over my head, but even if I just had a readout of OBD data, I feel like I could make more intelligent desicisions about manual EFIE and/or PWM adjustment. Yeah, I know about the $160 scangauge, but wouldn't it be cool have the data presented graphically (& in COLOR)... without an OBD interface that needs a laptop? (I don't have one)

ICEMAN.KCMO
07-24-2008, 02:57 PM
something you should check into is Apex'I SAFC... What it sound like they have is just a basic "Fuel Trickery" device with cell temp moniter... Apex'I has the SAFC and SAFC2 that does the job better minus the cell monitor. It will moniter RPM, MAF/MAP Input, you can Just alot of fuel.... check it out.. you can pick one up on Ebay for less than $300.

dennyk159
07-25-2008, 08:49 AM
Thanks Iceman
I checked out the SAFC2, & found that it is discontinued. There was one on ebay, that sold for $350ish. The new SAFC Neo is going for $359 new...

ICEMAN.KCMO
07-25-2008, 12:49 PM
iam actually picking up an SAFC 1 i think... it might be a 2.... anywho, i found it for $150.... I real good deal if it is a 1 or a 2... i also picked up my Wide band o2 setup for my car.. I am going turbo with this car soon and that is why i am getting all this stuff.... I am experimenting with the HHO first and probally will take it off and put it on my daily driver. I dont know how well HHO and turbo would do... I would think it would be hard to tune.

Tuning... What are you guys doing to tune you car??? are you going strictly off the true A/F ratio?? If so... what kind of A/F are you getting?
Also, Are any of you guys using a Pyrometer?? I would think that is essential to tuning... That is going to be the next thing i am going to pick up... you can be runnning an A/F around 14 and still have too high or too low egt.

ICEMAN.KCMO
07-31-2008, 11:20 AM
if you are interested, i know of an SAFC2 for sale for 150.. Safc also has a great feature of knock sense.... alos, what kind of EGTs are you running?

JonDoh
08-04-2008, 07:21 AM
Link Me

Link Me!!!

:d