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I'm acquiring the pieces needed to install ITBs on my car. Lately I've been thinking about all the little details like where to locate the GM IAT sensor and stock IAC valve. Below is a picture I found of a VW showing the IAT sensor mounted to the airbox flange. Please show me your trick Miata setups so I can visualize clever ways to mount my IAT sensor and IAC valve. Thanks.

 

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^ that's a really good idea

most kits put the IAT on the lower manifold which will always cause some degree of heat soaking
 

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Put the IAT in a little hole in the strut bar and tucked the IAC down by the fusebox and wiper motor.

Very cool placement!, How'z those japanese kitchen sink strainers workin out for you?
 

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So I'm planing on getting some AE111 ITBs and will be using the stock NB IACV. I've seen people using the Maruha kit that appears to simply vent one of the valve's ports to atmosphere and the second gets vacuum from post throttle body valve.
A couple examples...






Obviously this works as every Maruha kit is set up this way but it is totally different from how it functions on the factory throttle body where one port is before the butterfly valve and the second is after. So the valve behaves basically like an air bypass valve.

Does anyone have info on this?
 

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Quinn wrote up a post about how he did it for his NB in his build thread.

It's been a while, but I have some updates worthy of posting.
Got tired of not having an IAC and dealing with sitting in the car for warm up and sometimes a stall when coming to a stop. Removed the factory IAC from the stock intake manifold. Cut an adapter plate out of half inch thick aluminum. Tapped it for barb fittings and wired it up. After dialing it in on the Adaptronic the car just got tad bit more easier to live with. For that I am very pleased.

















I know I am do for overall impressions of the car, but I want to be very thorough and do not want to rush it. I will have them up soon so hang tight.

Also, when looking up settings for the IAC on the Adaptronic, I stumbled across this thread: http://www.miataturbo.net/adaptronic-63/more-precise-throttle-transitions-65816/

Sure enough, my adapter board is wired incorrectly like the rest of them meaning the injector firing is incorrect. We worked with throttle pumps and the transient throttle settings for a while and got them as good as we could. I thought maybe some of the stumbling in the lower RPM's was just the nature of the ITB's, but now I think otherwise. Needless to say I am pissed. It is very possible some horsepower is being left on the table because of this as well, especially in the low to mid range. If I re-wire the plug, the tune is probably going to get thrown off. I am planning on doing some headwork in the beginning of the fall, but I am committed to finishing my NA at the moment. So I think I am just going to wait until then.
 

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I see he's got both fittings hooked up. One of them goes to the vacuum block which then splits to each runner post-throttle (I assume) but I can't tell where the second port leads to.
 

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I see he's got both fittings hooked up. One of them goes to the vacuum block which then splits to each runner post-throttle (I assume) but I can't tell where the second port leads to.
Yes, the top port goes to the vacuum block and the second vents to atmosphere using a small PCV filter. This is how the vacuum leak is created to bump idle. I originally routed them opposite of that way and the valve sounded like a mini peripheral ported rotary engine. It was actually quite funny.

Also, to contribute to the IAT sensor mounting part of this thread. I am using the factory NB one and I have it zip-tied dangling off of the hard line for the brake booster. I figured this is where the air will be the hottest next to the runner for cylinder #4. I'd highly recommend against tapping them into the runners of the ITB manifolds as some have done. Not only will that cause heat soaking (I don't care if the GM sensor is open element), but two it disrupts the air flow velocity in the runner. When I was helping CND_Eunos diagnose some issues with his Jenvey ITB's, his IAT sensor was heat soaking being tapped into the runner.

 
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