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Crank pully sync magnet placement wrong? and does IAT sensor go here?


lwrnclightner

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I have been putting together the ingredients for my turbo swap, and it's coming together quite "Niftily" if you ask me (Noobest of the Noobs).

 

1. Anyway,  I read through the sds install manual and  today as I spread my kit out (just to admire it) that my sync magnet is mounted on the inner radius which is where the trigger magnets A,B,C are mounted. Now the pully is scribed with the outer radius and a hole drilled just next to this magnet which is where I assume it was originally designated to go. post-41568-0-81302000-1413151034_thumb.jpg

   Now in my nooby brain I am thinking that this will screw up the trigger signal being picked up by the hall sensor and that it is not going to see a sync signal. Help me understand why this was done this way.

 

I guess if this was done in error I can drill the magnet out and place a new one on the outer radius where the manual states it should be.

 

 

2. Can someone confirm or clarify for me if my inlet air temp sensor goes in the 1" spacer where the red arrow is pointing.. or does it go upstream of the throttle body?  post-41568-0-23095500-1413150998_thumb.jpg

 

Thanks for any insight that you send my way!

 

Lawrence

Edited by lwrnclightner
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My turbo swap IAT went in the spacer block behind the throttle shaft.

The hole you show is cold start injector, and that's where my idle bypass was connected.

 

It may be easier for you to put it in the IC tubing or J-Pipe.

 

I'd use that big hole for idle air bypass...

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The IAT Sensor can be mounted anywhere from the intake manifold to the intake filter. There are pros and cons to each position. Factors to consider include vibration, heat soak, sensor type (and subsequent reading times and durability), whether the engine is going to be NA or turbocharged, tracked or daily driven, so on and so fourth. I would recommend reading through some of the discussions on the different Megasquirt forums to learn more.

 

Or just put it behind the throttle like Tony! You'll find that's what most people are doing (including myself).

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Correction: on an N/A it can go anywhere from the back of the intake valve to the air cleaner--most OEM's place it in the air box. I used the IAT from a '91 240SX on my 510.

 

On a TURBO car, though, the IAT MUST be from the intake valve to either the turbocharger discharge or the Intercooler outlet---ideally in the airstream with flowing air as close as practical near the intake valve for proper air density calculations of the air as used by the engine for combustion. If you place it in the air box on a turbo car you will never calibrate it properly for the temperature difference between on boost and off-boost operation...

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Correction: on an N/A it can go anywhere from the back of the intake valve to the air cleaner--most OEM's place it in the air box. I used the IAT from a '91 240SX on my 510.

 

On a TURBO car, though, the IAT MUST be from the intake valve to either the turbocharger discharge or the Intercooler outlet---ideally in the airstream with flowing air as close as practical near the intake valve for proper air density calculations of the air as used by the engine for combustion. If you place it in the air box on a turbo car you will never calibrate it properly for the temperature difference between on boost and off-boost operation...

 

Ok, now I am starting to get the picture, well for the IAT anyway. So let's see if I have this right.  If I plan on running a water/meth inj in addition to the intercooler, then the IAT sensor should be after both of them but as close to the throttle body as possible, am I on the right track there?

 

 

My turbo swap IAT went in the spacer block behind the throttle shaft.

The hole you show is cold start injector, and that's where my idle bypass was connected.

 

It may be easier for you to put it in the IC tubing or J-Pipe.

 

I'd use that big hole for idle air bypass...

 

Now I must admit that the idle air bypass has me a little confused, only because I will have the intake build that Senza Pari provides (if the group buy #2 ever kicks off). I will start to research exactly how the bypass works and what type of device I need to implement it.

Here is what I will attempt to find, let me know what I am missing from my list...

1. What a idle air bypass looks like and where to obtain one (new???)

2. Where does it terminate to?

3. How is it controlled?

 

When I brought this car, I had no idea that I would be learning all this fun stuff. I can't wait to get it running and feeling what it feels like to be in tune with your ride, to know whats going on inside and out.... To be one with my ride...

 

Kudos to you guys for being here and pointing me in the right directions, as I go. 

 

Hey Tony D, you remember my first post,,, asking what these were? post-41568-0-46655200-1413250044_thumb.jpg

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If you spray meth, put it downstream of your I/C and BOV, with the IAT downstream of it all... Nearest the T/B

 

As I said, ideally it would be in a runner to the intake port, but heat soak becomes an issue in low speed running with the non-cross flow head. The plenum isn't so bad, and a handy spacer between plenum and T/B makes for a handy multiple-point access-all point.

 

Idle air bypass is integral in N/A T/B's of old, and then to simplify the casting in 82 they went external. Now the L28ET had a vacuum controlled idle speed air bypass, but in Europe, the L28ET had the exact same idle air bypass as the N/A cars did....it's connected before, and after the throttle plate (mine is in the J-Pipe, and goes in the old CSV hole.) this allows the throttle plate to be 100% closed at idle.

 

This is the one I used:

40590d1297375796-no-idle-screw-idle_adju

 

Now, modern cars use fancy IAC Valves that idle up, fast idle, speed control for high alternator or A/C loads, but really the simple fixed bypass is easy to do and works great. The stock N/A bypass screw used 10 or 12mm hoses, way overkill! I pulled those fittings out by heating the body with a propane torch (like hot melt glue on them) and then tapped them for 1/4" hose. I used FI. Hose since I run 20+ psi of boost now and then, so it won't blow...the 1/4" line is good for zero to 2200 rpm. If you REALLY want idle up for fast idle, and A/C put some 12v solenoids found on modern vacuum operated accessories like EGR, etc, and hook on the J-Pipe side of the hose and idle bypass screw...I used a carb jet to give me fast idle, run off a GPO output configured to open at below 150F, and another relay hooked into my A/C clutch circuit so when the compressor pumps, it idles up. You and use idle bypass screws on each one if you wish, then you can adjust the speed to suit. I find a fixed orifice once defined by trial and error works fine.

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  • 3 weeks later...

Thanks fellas!

 

Well what I now know is that the sds 2 doesn't use idle air control, so am I correct to assume that I will have to tweak idle air by adjusting the screw that holds opens the valve on the 240sx tb in sequence with the fuel adjustments that I dial into the sds controller?

 

If so then I am really going to be an "old schooler"!

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