AIT sensor install question?
 

Anyone know the drill/tap size for the GM open air element AIT sensor? I've been looking online and I am getting conflicting answers. Most say 3/8 NPT, but it is way bigger than 3/8". I'm thinking 5/8" maybe? Just trying to get the right size tap to install it into the IM.

3/8" NPT is right, you'll need a 9/16" drill bit. The "3/8" is supposed to correlate to the inside pipe diameter, but in reality it doesn't mean much.

Definitely a 3/8" NPT

ya 3/8", dont tap all the way through, go maybe halfway down the tap. Heres my AIT. I like showing off my work :)

Attachment 216913

Nice stuff. If your IM is still on the car, it works just as well in the IC piping near the TB. After all, in a stock application it's waaaaay over there in the AFM.

So wait you dont tap all the way into the intake manifold?

dont use all the threads on the tap because it will make it too loose, you want the sensor to fit snugly.

Thanks guys. Got my NPT tap kit and saw the size of the tap and it all made sense. Now just to get a 9/16 drill bit and I'll get crackin'.

Good Luck BRGRacer. I am not too far behind you. I have MS built and just need to finish up some testing and make sure it is good to go, then I will be installing it. I chose to go with the IAT as well and not use easytherm. Nice looking manifold.

3/8 npt. I bought a 3/8 npt pipe bung and welded it to my intercooler pipe just before the TB. I don't like the idea if drilling my manifold one bit.

You don't tape all the way because NPT threads are tapered so by taping only half way you keep a smaller taper so that the fitting can actually snug up in the threaded hole. If you tap all the way in it will just sit in there losely.
Use some sort of sealant on that sensor as well when installing.

its a tapered thread

tappin the manifold would be pretty sweet if you're running WI. IC pipinig is easier and works fine though.

mine is gonna be sitting by the air filter for a while

So do you have to install a bung if you want to do the ic piping?

I'm thinking there isnt enough thickness on the piping to just drill and tap?

my pipes are aluminum so i guess ill just tap the intake manifold if i can tap the pipes

I doubt you'll be able to tap an IC pipe. There's not enough thickness.

I got the sensor kit from DIY-A that included a steel bung, so I welded it up. https://www.miataturbo.net/forums/at...1&d=1179271878

you could tap it but it would require a set nut or a welded on bung.

Thats gay, i ordered from them and they didnt give me a bung.. what size threads go for that bung? the reason im asking this is my IC pipes are aluminum, wouldnt it be a PITA to weld a steel bung onto alum. pipe? I think ill just tap the intake manifold..

How deep is the wall on the intake manifold where i'm supposed to tap it at?

diyautotune.com has an aluminum 3/8 NPT bung for $9: click!

Cheers!

Jeff

Sweet thanks

I guess i'll just tap the intake manifold, i kinda need it by this weekend and it would take too long to get it shipped here and stuff.. oh well, how thick is the wall on the intake manifold? who all has done it? how do you clean out all the shavings it makes

mcmaster holmes!!! they're not 9 bucks I dont think. it's 3/8npt

get an Al bung and TIG it on to your IC pipe.

I wouldn't tap the intake mani, if the mani is on the motor. And it's a lot of work to remove it from the motor. Easiest thing is to pull the charge pipe at the t-body, drill, weld, and go...

.99$ bung from ACE Hardware....get a 1/2" Compression fitting sleeve.

the threading is 3/8" and the hole for the "line" is the perfect size for the sensors element to fit through.

http://images.orgill.com/200x200/1182914.JPG

Ok ill do that thanks

Ok i have a question.. I'm trying to order some taps online because earlier i went to lowes and other stores and they didnt have any that i need..

Whats the difference between a NPT tap and a NC tap.. the reason i ask is i found a 3/8" NC tap at lowes but it was tiny compared to the 9/16" drill bit im supposed to use, so i'm guessing they use a different way to measure it?

Autoparts stores carry NPT taps individually pretty commonly.
The NC tap is not close to a NPT tap. The NPT taps are larger than what you sould assume they are and they are tapered for a compression fit when tightening.

Harbor Freight had a tap kit on clearance in their last ad. Go there, if there's one close.

ok thanks a lot

This is still annoying.. i cant tell what tap set is NPT and what is other kinds.. I found a 3 peice with 2 of the 3 sizes i need.. I guess ill try auto parts store or something

nc = national coarse thread
npt = national pipe thread

pipe thread is based on pipe size which doesn't really correspond to the outside diameter of the pipe...

and it's tapered.

when you find the right one, it will most likely just say 3/8" or 3/8-16 or something, NC is not NPT.

Uhh dude you do know that there is no way to weld aluminum to steel, that i know off. :nuts:

intake pipe... you could braize it.

ok thanks

I would do the intake pipe due to known heat soak issues with intake manifolds.

Here's how and where I've fitted mine
Attachment 216330

That's the perfect position... just before the throttle body...

Umm assuming you not supercharged surely Jerry ;)

For my intallation with a picture in page 1 of this thread, I removed the manifold and would not consider doing it any other way. For me it was pretty much an easy task, but it takes some time ... maybe a few hours. I painted it black at the same time.

Would fitting a dump valve opposite my IAT sensor have any adverse effects?

Thread from the dead....question about IAT location S/C
 

Hey sorry to bring back an old thread but I'm trying to figure out where to put my IAT sensor when I install my new MS. There's a comment here about 'assuming your not supercharged'. Can anyone explain this?

I have a 95 and am currently running an Eaton M45 S/C. The car came this way and it's my intent to install / learn / tune the MS this year and then go turbo with (probably) a BEGI setup next year.

So with a S/C where's the best place for the IAT without tapping the intake mani? BTW - I have the plastic crossover tube.

It needs to measure actual air temp as it enters the intake. So after the SC and if you were to have an IC then after the IC. Since you don't.... it needs to be after the SC so it's reading the temp of the SC heated air as it enters the engine and can account for that properly. If it's a plastic tube... um... JB weld a bung to it maybe? A metal tube you can weld a bung to. But that's where it needs to be or you'll have issues.

Thanks! As I thought. So I can just do as richard_ha did in the photo above but just before (or in) the dummy TB.
I plan to try out water injection too. I assume this won't be an issue for the IAT sensor in any way as long as the water is atomized in the crossover tube before it hits the sensor?
My pre-built MS is on the way! What exactly do I need to order from DIY for MAF deletion? It's not coming with the IAT sensor, is that all I need? Which one, the one with the pigtail I assume?

GM IAT. The MS has a MAP sensor in it. Just run a vacuum line to it.

You'll want the open element one, and a bung to weld it in.

Excellent. Exactly the info I needed.

Hey richard_ha...if you happen to see this, how did you secure your IAT?

Anyone know the answer to this?

I doubt there would be enough issues to matter. If the sensor can measure the temp of the air coming into the intake then it should be fine. Air escaping out the BOV shouldn't make that big a difference. Maybe if it leaked at idle and caused a 10* change for some reason you could have issues. Not like you couldn't tune for that though.

You just aren't baller enough. I tapped my IC pipe, no problems. I used JBweld to seal it up afterwards, though.

(don't do that.)

FYI, NPT is measured differently than bolts and shit..

Why not do it right before the throttle body? Piping there vs. the IC piping would seem best to me.

The BOV across from the IAT/MAT should be fine, it's venting air out and not in as long as it's functioning properly, and when the BOV is open you're not under load, again assuming it's functioning properly.

On plastic pipe... um... either epoxy a bung to it, or I've actually heard of people drilling a hole, and putting the bung INSIDE and threading the sensor through the hole into the bung holding it in place. But that's usually the ghetto o2 sensor mount and I don't think I'd do it on an IAT as it would be really ghetto and dangerous if it came loose. Not to mention hard to seal up under boost.

Really the best answer may be incorporating some aluminum pipe...