Modding the Air Intake for MAF delete / IAT install
 

Getting ready to install my DIYPNP and I'm curious what the preferred method is these days for modifying the stock intake to accommodate an IAT sensor. I came across this post and that seemed like a good way to handle it.

Does anyone make a straight pipe with an IAT bung to bypass the MAF and go to the stock airbox? Assuming that would work. Or is the cone style a better option?

Attachment 233331

add a turbo.

That's the long-term plan. I'm hoping to get some tuning experience on N/A first. Looking for a clean and simple solution in the meantime.

I'd want the AIT within the airflow, not just near it.

silicone intakes?

http://www.siliconeintakes.com/holse...er/-p-500.html

though you'd need 3/8NPT for a GM IAT

I'd want that same thing but as an aluminium pipe. Clamp the stock crossover to one side, and the cone filter to the other.

are you talking long term or short term?

*edit: I type slow.

just put it into the airbox. Works fine short term

IAT Sensor Adapter Tube

https://www.miataturbo.net/attachmen...ine=1432213827

yeah that.

I literally stuck mine into the snorkel and let it sit on the filter, that's about as much "in the airflow" as you need

I like this solution too. Dont use a cone filter and just tape/screw it--prefilter-- inside the airbox.

This is probably the most elegant way to do it. Do you know offhand if the tube adapter would need to be 2.75" or 3.0"? If not, I can measure the stock tube where it meets the MAF next time I get a chance.

I really like this solution
I'm leaning toward this route. The only thing stopping me is being realistic about how long "short-term" will actually be.

if nb then 2.75
don't remember na size

the other up-side to my solution is that the whole sensor is inside the airbox, and in the path of airflow, thus significantly helping reduce or prevent ait heat soak

If you know someone with a 3D printer I can send you this file. I have one with the proper IACV port location for the 1.6 and the 1.8

https://www.miataturbo.net/attachmen...ine=1427427981

https://www.miataturbo.net/attachmen...ine=1427427981

that's properly the worst possible spot for an AIT.

Due to radiator heat soak? I can move it to the outside top of the elbow. Or draw up an inline adapter to be 3D printed similar to the metal one so you can put it wherever your heart desires.

It's rare that I agree with Scott, but this is, in fact, not an especially good spot despite the fact that both Bell and FM put theirs there.

Placing an IAT sensor directly behind the radiator exposes it to a hell of a lot of hot air, and even though the fancy GM-style "open element" IAT sensors aren't supposed to heat-soak externally, they always seem to. The result is artificially elevated IAT readings.

I had reasonably good success drilling and tapping the cold-side end tank of my intercooler, and placing the sensor there. It would obviously heak-soak just a tad after you parked the car hot, but once you re-started it and got moving, the sensor seemed to cool off and give believable readings while in off-boost cruise.

Changing topic slightly, I find this extremely interesting, and am curious as to both the material from which that part is made as well as its long-term durability.

I'll revist my IAT location and try to figure out a better solution.

Material is 3d printed ABS then acetone vapor bath which helps smooth the part, seal it, and bond the layers together better. I printed this at 0.12" wall. Replicating the 1.6L OEM tabs and rubber mounting style did not work well. The tabs were too thin. I switched it to the traditional hose bead and silicone coupler mounting style. I want to start experimenting with nylon which is less brittle than ABS and might be a better material choice for parts like this.

I design aftermarket intake for a living and we run 3D printed prototypes for 2-3 months on vehicle while the production tooling is being made. I have not seen any failure or degradation in the 3D printed ABS parts. We usually use 0.15" wall thickness. However, these are street vehicles that don't see the extreme abuse of track cars. I've run that intake at 1 track event so far without any issues. I'll be keeping a close eye on it and always take the spare stock tube with me.

ShmoozerJoe has one of those things (one of those cobra looking intake tubes), and (correc me if I'm wrong, Joe) it's ABS plastic.
And his cracked last wednesday. Right down the middle

Reporting back. The intake hose is 3" and the MAF inlet is 2.75" on my 95. If I go with the aluminum adapter, it will be 2.75" diameter and should pair up nicely with a cheap 3" cone filter on the other side.

I'm planning on putting in the new ECU this weekend so I'll put the IAT in the airbox for now. If it's not too ghetto, I might just leave it there.

Thanks everyone for your input.

It did. Right at one of the seams in the print.
I haven't heard of anyone else having this issue... fairly certain it's due to the lousy quality print.

Undersized, rough even with the acetone vapor bath, etc.

I'm being patient and waiting for Alec to manufacture them in CF. Silicon tape for my temporary win.

I just ran a 3/8 NPT tap through the intake plumbing then screwed the thing in, I had it for the oil pan anyway. Not optimal, but it worked and it was free. Not a lot going on with no turbo, not like it's going anywhere.

This is how it's done. Temporary permanent zipties.

Attachment 184076

I also put my IAT right before the throttle body before I had the turbo installed. It heatsoaked.

I ended up tapping a hole in the buttom of my airbox, which was marginally better. It still heatsoaked.

I picked up a non-functioning MAF housing + gutted the sensor pocket + drilled a hole for the sensor and epoxied a 3/8NPT bung in place. Figured if it was a good location for stock it was good enough for me. It lets me use the stock crossover tube + filter housing or aftermarket.

It worked fine for 2 years of non boosted driving.

https://dl.dropboxusercontent.com/u/...a/IMAG0168.jpg

<p>if youre keeping stock intake, just toss the sensor in the air box. &nbsp;why drill? &nbsp;litterally duct tape it inside the box pre-filter.</p>

I assume it doesn't matter whether the sensor is located upstream or downstream of the air filter?

<p>well let's see: do you want to ingest an AIT sensor into your intake or not?</p><p>&nbsp;</p><p>it might be why i've said pre-filter like 15 times now, but by all means duct tape an ait sensor inside your IM for more accurate temp readings just before the air reaches the clyinder.</p>

I apologize for the insufficient clarity in my question. Allow me to re-word:

I assume it doesn't matter whether the sensor is secured--by screwing into a threaded insert securely mounted (e.g. glued or welded) to the intake plumbing--upstream or downstream of the air filter?

<p>and we are still assuming compeltely stock plumbing?</p>

Well, mostly. I mean, if you have a cone filter like deezums or bahurd, above, I don't imagine there's really anyplace to fasten it upstream of the filter, so my question wouldn't really apply. But the stock tube to the air box or a Randall would constitute "upstream".

<p>yeah, I wouldn't think it would matter so long as it's in the airflow;&nbsp;that's really what's important.</p>

I designed and 3D printed a replacement piece for the MAF. 3Dprinted file has threads for the GM AIT. Works great as a solution until I get my ITBs up and running. Let me know if you want the file.

https://www.miataturbo.net/attachmen...ine=1432881261
https://www.miataturbo.net/attachmen...ine=1432881261
https://www.miataturbo.net/attachmen...ine=1432881261

Whoa that's pretty cool. I ended up ordering the aluminum one from Bell, but you should post the file so others have the option to use it in the future.

The one I ordered from Bell a couple years ago was an overpriced piece of crap. Be prepared to cut down the length of the threaded nipple and then re-tap it so that the element of the sensor is actually in the path of the airflow.

I mean, maybe Bell has started paying attention to these kinds of details in their production process? But I doubt it.

I am slightly annoyed by the fact that this piece has neither a kitten nor a large cock embossed into it.

I'd be interested in the file as well! Thanks!

Sorry to hear that. Hopefully I'll have better luck. I'll share the results after it arrives next week.

Uploaded the file to thingiverse. If you download and print it, please include a picture of it installed :party:

MAF Replacement for the Mazda Miata by teejay187 - Thingiverse

Feel free to make a remix of the file :giggle:

I received the aluminum MAF delete/IAT tube adapter from BEGi and, while the depth was accurate, the sensor did not thread. I called customer service and they explained it probably got warped during the welding process. They offered to send me a new one, but I had access to a machine shop to re-thread it so that wasn't necessary. They put a credit on the account instead. For the price, it did seem a little flimsy so I can't give it a strong recommendation:

tl;dr: Part was defective and thinner than expected. 2/5 stars. Bell Customer service > quality control

Sounds like BEGi wins again.:rolleyes:

If a person was gonna DIY something like the BEGI part, is any one metal better than another--aluminum, mild steel, stainless, etc? Heck, even PVC?

Whatever you feel comfortable working with, provided it won't melt.

One time I needed a quick fix for an IAT mount so I epoxied (probably JBWeld) a 3/8NPT weld bung into a straight section of 2.5" OD aluminum tube. I scuffed the hell out of the surfaces and used a generous amount of epoxy and it held up fine. Sure it looked like ass but it worked! I wouldn't recommend this for a long term solution, but I'm sure you get the idea. I replaced it with a unit of similar construction, only welded instead of epoxy.

I can inform that my 3D-printed part is still holding up just fine after 3 months now. No deformation.

Not sure about PVC, since it is pretty close to the exhaust manifold, but the OEM toobs are plastic and they don't melt (although they could be some kind of heat-resistant polymer). But using the same reasoning, I figure any metal should be OK. I just can't bring myself to pay $35+s/h for something like the BEGI part that I think could easily be DIYed for $15 in materials.

Hey there - for some reason, shapeways is not happy with the dimensions of this STL. Could you list them real quick for me? 2.75" od? 2.5" id? What length? Thanks!

Try scaling it down 10 times. Length should be 120mm.

Sorry about that. I always model in 10 or 100:1 because Sketchup is stupid with small measurements.

I hate to resurrect a dead thread, but it seems as if the thingiverse link has either somehow changed or the “thing” is gone. I’d doubt you’d still have the file by chance, but if you do, I’d be interested in a copy

A simple search of "miata iat" on thingverse and I found this: https://www.thingiverse.com/thing:5322754

Yep, that's the one I shared. It worked pretty well but heat soaked like mad. But that's honestly to be expected given it's location and plastics poor ability to dissipate heat.

It was a decent temporary solution as I learned the ECU before I went turbo.