I am in the middle of installing a vortech v2 sq on my 03 gt. i bought the lightning 90mm MAF, and i also bought an external IAT sensor. But couldnt i just swap the whole sensor out of my stock MAF and put it in the 90mm MAF so that way it would have the IAT sensor already in it... its an exact fit, is there any reason why that wouldnt work. If not, what exactly do i need to do? any help is greatly appreciated, thanks.

 

You could, but it would be a bad idea. A very, VERY bad idea.

First off, switching your stock element into a much larger tube will make the air mass vs voltage readings completely wrong. Your MAF works by heating an element to a certain temperature, and then figuring out how much voltage it took to achieve that temp. However, this voltage is only useful when the exact volume of the tube being measured is known. When you swap your old sensor into a new, larger tube, the voltage readings will be completely different, and you'd have to rebuild the entire MAF transfer function by hand. It would be a royal pain to tune, assuming you ever got it working.

Secondly, the stock MAF meter will peg with your setup. Even if you could somehow fashion it together and hand-build a tune, your meter would peg, your engine would go very lean up top, and you would eventually destroy the motor.

And, if all that wasn't enough to dissuade you, and somehow you took care of everything from the custom tune to the pegging issue, you still want the IAT to go after the blower, and as close to the TB as possible. If you don't do this, then your ECU won't know the actual temperature of the air entering it, and will not be able to compensate for the 100*+ temperature change given to the air by the blower.

When this happens, your engine will (among other things) advance timing too far. This can lead to detonation and engine damage rather quickly.

So in conclusion: No, you would never, ever want to do this. You are actually better off with the LMAF not having the temperature sensor built in, as now you can put it in the discharge tube and get accurate air charge temperature readings for your ECU.

Ditch the stock MAF, install the LMAF, and put the external IAT in the discharge tube, preferably close to the throttle body.

 

Ok, so if i put the IAT in the discharge tube, close to the throttle body, how exactly do i go about wiring it? i noticed that the lightnin MAF has 4 prongs and the harness that went to my stock MAF has 6 prongs, do i need a new harness? Will the 4 prong just plug into the 6 prong harness and i wire the IAT into the harness where the other 2 prongs are? thanks

 

You're on the right track. The extra two wires in the harness are for the IAT. I'm not sure which ones they are because mine didn't have the IAT integrated.

I'm also not sure if you can use the same harness or not. I would think a simple test would be to see if the LMAF fits in the stock harness. If so, then just cut off the two wires that don't connect to anything and run them to the IAT.

I'm sure someone else on here will know which wires to cut and if the harness fits. Unfortunately, I'm pretty useless for that.