This might be kind of a dumb post, but why would it be so hard to get a MAP/IAT combo to work on our cars?

Seems like all that would need to happen is a bit of research on a good IAT/MAP combo and their voltage outputs and a couple mathematical formulas using their output voltages would have to be done, then make a little black box with a microprocessor in there to do the math and spit out a voltage for the ECU to see and you'd be set. Oh yeah, and of course a potentiometer for injector correction.

Am I missing something? Ive heard that such devices have been made but cost a ton of cash. Im no electrical engineer, but it doesnt sound too overly complicated to me.

I wouldnt doubt theres even someone on this board whose smart enough to figure it out. Add a couple of dials and voila', a product that could be universal for any MAF car.

Comments?

There are a couple of tech heads that patrol here. Maybe you guys can brainstorm. As of now, the AEM EMS is the biggest thing coming down our paths.

WD

Don't know much about MAP sensors, but I do have an EE degree and love DIY stuff... so I'll chime in.

First off.... materials. Microprocessor, either with internal or external ROM for the correction map. Does the MAP sensor require a control circuit (kinda like a WB02 sensor)? Couple of regs, maybe just one. Potentiometer... or much better have the uP have some serial connection to the PC for tuning... not that hard anyway.

Now... here comes the problemas I see. You would need the MAP's and IAT's response curves... you could possibly get that from datasheets... possibly. You would need to match one to the other into some kind of 3d map. X = T, Y = P, Z = Air flow. It ain't difficult, just a couple of equations I believe could solve that but I would need to look into the response curves to be sure.

Tha biggest issue is the original MAF's response curve. You won't get that easily. To get it you would need some kinda of test equipment to pass a measured amount of air/sec through the MAF to get the voltage returned and from there get the response curve.

If you get all 3 response curves all you would need to do is find the linear equation that would convert one (3d based) into the other (2d based) and program this "map" into the microprocessor. The uP would just read the IAT and MAP, resolve the equation and output the correct MAF voltage.

Yeah, i forgot about getting the curve from the original MAF, that'd be the hardest thing to get ahold of (or do testing to get). It'd require some pretty fancy machinery, or a sidewalk blower and another MAFS that you know has a linear voltage output. (pretty smart, eh?)

If im not mistaken GM MAPs have a linear output, and I would assume IAT sensors do as well.

But even if the GM is linear you still need the response curve (or line, whatever you might wanna call it).

Right, but thats what hooking up the linear maf (if one exists) and the stock maf to a blower would help figure out. does that make sense?

No... cause you still need the linear MAF's equation to determine the stock MAF's equation.

Linea MAF -> x CFM = y V => x/y CFM = 1V => k CFM = 1V

You still need k.

I have no idea what most of that means, but I trust your judgement.

MAFS is better system anyhow right? why go to map?

are you talking about just using the map for airflow metering? i think it would be cool if we could interface it with the load map so we could retard timing as manifold pressure increased. that seems like a whole bunch of work just to use a different airflow meter....just my opinion.