Best Location for IAT Sensor

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hutch
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Best Location for IAT Sensor

Postby hutch » Fri Feb 05, 2016 1:58 pm

So I want to start getting some things prepared for my next T5 install and the next piece on the checklist is where to place the IAT sensor. I was thinking these would roughly be my options:

a) onto the intercooler pipe like my SPG and stock T5 cars

b) onto the TB, maybe where the cold start injector would be? I haven't really looked into clearance issues but will hopefully this weekend

c) drill and tap a hole for it in the manifold, maybe down between the 2/3 runners so I don't risk any hod clearance issues.

Option A seems like the best since thats how they came stock but I can't weld aluminum (or anything :lol:), though its not difficult to pay someone to do it for me. Option B may not even be feasible and likely more work than is necessary. I was thinking about option C and using the manifold since I have a cleaned up one I was going to swap in anyway, obviously I wouldn't try this with it attached to the engine, but I was reading some people suggest that the manifold would act as a heat sink and could impact the sensor's readings. While I agree that could happen in a textbook I'm not so certain about the real world scenario, though I would love to hear people's thoughts on it. This is going in an otherwise stock convertible so I will not be looking to eek out every last HP but it will likely be driven in hot conditions so maybe it would be a thing.... So whats the best place to put this thing?

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99Super
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Re: Best Location for IAT Sensor

Postby 99Super » Fri Feb 05, 2016 2:22 pm

Hutch,

I drilled out one of the bracket bosses on the side of the TB and tapped it for the IAT threads. I'll get you a photo in a bit.

John

hutch
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Re: Best Location for IAT Sensor

Postby hutch » Fri Feb 05, 2016 3:11 pm

Hmm sounds interesting! I figured there were a few places that you could thread but without a TB in front of me I couldn't remember how far the butterfly valve went to maybe get in the way.

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squaab99t
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Re: Best Location for IAT Sensor

Postby squaab99t » Fri Feb 05, 2016 3:20 pm

I have mine down stream of the blow off valve and prior to the throttle body. Yes, requires welding. Bung on the left of the tube. Don't be temped to try and put a nut on the back side. That kinda nut sucking is no good.
image.jpeg

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Re: Best Location for IAT Sensor

Postby jdwertz » Fri Feb 05, 2016 3:35 pm

Here is mine drilled and tapped on the TB:

Image

hutch
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Re: Best Location for IAT Sensor

Postby hutch » Fri Feb 05, 2016 5:21 pm

Definitely like all these methods!

So assuming price and difficulty level is about even for all of these, is there one that would be more reliable or accurate in the long run? I just remembered I actually do know someone who could weld Al and would probably do it for cheap/a jug of homebrew, and a drill and tap set would probably be $10-15 tops so we'll call it a tie.

I was thinking with the coolant lines running through the TB its probably just as hot as the manifold, so again a tossup. I guess this could affect sensor lifespan though realistically it would take me years to put those sorts of miles on this car. Would the IC pipe be the most accurate in terms of temperature reading, or is the air moving so fast through the system that it likely wouldn't make a bit of difference?

(Should I stop worrying about it and just pick one? :crazy: :lol: )

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Re: Best Location for IAT Sensor

Postby jdwertz » Fri Feb 05, 2016 5:30 pm

hutch wrote:Definitely like all these methods!

So assuming price and difficulty level is about even for all of these, is there one that would be more reliable or accurate in the long run? I just remembered I actually do know someone who could weld Al and would probably do it for cheap/a jug of homebrew, and a drill and tap set would probably be $10-15 tops so we'll call it a tie.

I was thinking with the coolant lines running through the TB its probably just as hot as the manifold, so again a tossup. I guess this could affect sensor lifespan though realistically it would take me years to put those sorts of miles on this car. Would the IC pipe be the most accurate in terms of temperature reading, or is the air moving so fast through the system that it likely wouldn't make a bit of difference?

(Should I stop worrying about it and just pick one? :crazy: :lol: )


I am deleting my coolant hoses to the TB. No need for them because racecar. :luke:

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99Super
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Re: Best Location for IAT Sensor

Postby 99Super » Fri Feb 05, 2016 5:33 pm

My location is the same as jd's...

IMG_20160205_144635401.jpg


I guess Wertz and Wirt think alike!


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Re: Best Location for IAT Sensor

Postby gmreider » Sat Feb 06, 2016 10:56 am

Hutch, I like the sensor on the intercooler pipe before the TB. I'll make up the weld on bung for you once you decide on IC pipe sizes. The bung should be radiused to make a nice weld up fit. Don't buy the taps either, I have them and I am fairly close to your location.

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Jordan
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Re: Best Location for IAT Sensor

Postby Jordan » Sat Feb 06, 2016 3:48 pm

I'd do the welding for some home brew. I can send down with your harness if you like. Unless you aren't using a stock elbow or if Gary can Tig now

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Re: Best Location for IAT Sensor

Postby hutch » Sat Feb 06, 2016 7:29 pm

After spending the day at Gary's I think he's going to build something pretty nice, similar to what Dennis has in his picture. We were sort of going over the various options and figured that would be the best choice. I would still be curious to do some data logging and measure if there is an appreciable difference in the various locations. I would think that the charged air is moving fast enough to not be too effected by any heat from the manifold or TB but it would be fun to know :dunno:

I'm always happy to share homebrew but the laws in this country are absurd relics of the Prohibition era. Similar to buying a 'water pipe' at a Phish concert, I can only send 'yeast samples' as I wouldn't dream of shipping beer ;) (especially using USPS!)

Not to mention the grey line that is selling alcohol for goods or services that quickly becomes a Federal issue... but I've got a nice Scotch Ale and a 100% Brett Session Ale on tap right now. Theres also a sour beer thats about 8 months into its year long hibernation that I'm getting excited to open. I'm hoping to make an eeuro meet this year so hopefully I can bring some up

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Re: Best Location for IAT Sensor

Postby squaab99t » Sat Feb 06, 2016 9:44 pm

Gotta have the booze to weld well. Steadies the nerves.
image.jpeg

You will still need a tap to chase the threads as the welding with good penetration will distort ones down below.

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Jordan
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Re: Best Location for IAT Sensor

Postby Jordan » Sun Feb 07, 2016 5:26 pm

hutch wrote:After spending the day at Gary's I think he's going to build something pretty nice, similar to what Dennis has in his picture. We were sort of going over the various options and figured that would be the best choice. I would still be curious to do some data logging and measure if there is an appreciable difference in the various locations. I would think that the charged air is moving fast enough to not be too effected by any heat from the manifold or TB but it would be fun to know :dunno:

I'm always happy to share homebrew but the laws in this country are absurd relics of the Prohibition era. Similar to buying a 'water pipe' at a Phish concert, I can only send 'yeast samples' as I wouldn't dream of shipping beer ;) (especially using USPS!)

Not to mention the grey line that is selling alcohol for goods or services that quickly becomes a Federal issue... but I've got a nice Scotch Ale and a 100% Brett Session Ale on tap right now. Theres also a sour beer thats about 8 months into its year long hibernation that I'm getting excited to open. I'm hoping to make an eeuro meet this year so hopefully I can bring some up


I just a got a "beer of the month" delivery someone got me as a gift through UPS. How does that work?

hutch
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Re: Best Location for IAT Sensor

Postby hutch » Sun Feb 07, 2016 6:46 pm

Short answer (and not that I'm an expert in the slightest :lol:) is you're buying, and paying taxes most importantly, from pros with licenses, etc...

Theres a lot of gray area with making beer at home, chances are you'll be fine as people ship beer all the time but theres always the chance you catch the attention of the wrong ATF agent :-O

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Re: Best Location for IAT Sensor

Postby DrewP » Mon Feb 08, 2016 2:13 pm

Jordan wrote:I'd do the welding for some home brew. I can send down with your harness if you like. Unless you aren't using a stock elbow or if Gary can Tig now


Speaking of harnesses.... ;)



squaab99t wrote:Gotta have the booze to weld well. Steadies the nerves. .



And the hands! At work, we call it "welding fluid."
"You can educate ignorance, but you can't fix stupid."


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