What sensors do I use for Throttle Bodies?

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What sensors do I use for Throttle Bodies?

Post by PugMonkey »

Hi All,
I am putting together a MS2 v3 as we speak. At this stage I have the board talking to the laptop but I have a long way to go. What I would like to know at this stage (so I can purchase them) is what sensors am I going to require. Detailed here is the setup I'm preparing for. The engine has individual throttle bodies, 4xLS1 coils (i read about a transistor mod I will require for this), fuel injected and will not be mating to any other OEM electronics.

I have read through the manual and just can't put my finger on what I am missing. Idle control valve is now non existent because of the ITB's, Manifold air pressure - well that's all gone too. What do other guys use with this setup?

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Re: What sensors do I use for Throttle Bodies?

Post by devojet »

Im running a v8 with individule throttles. It uses the internal map sensor, tps, o2, coolant temp and water temp. Plus crank sensor and cam sensor.

For the map sensor I commoned up the lines from each of the manifold runners and use the itb mode for tuning.

You could just run tps and no map.
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Re: What sensors do I use for Throttle Bodies?

Post by long283 »

There are a few options to use they are all basically a 10kOhm potentiometer. With a connection to +5/12VDC, ground(-) and one signal connection that gives a voltage between (+) and (-) relative to the throttle position.

Have a look at what will be easy to mount to your setup. There are usually two screws to mount the sensor and the sensor fits on the end of the shaft. The shaft is usually round with a flat on one side (D-shaped).

Here are a few;
http://www.efihardware.com/products/386 ... witch-spec
http://www.efihardware.com/products/c22 ... -and-Parts

Running TPS and RPM without a MAP or MAF signal is called Alpha-N mode. It works well for wide open throttle but if you can tap into each runner and have a small manifold with the MAP signal you can get a better cruising tune.

Best of luck.
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Re: What sensors do I use for Throttle Bodies?

Post by PugMonkey »

I'm presuming the Cam sensor is via a 36-1 trigger wheel? I will have trouble getting a MAP set up. Is it a must have?

Thanks for the replies everyone.
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Re: What sensors do I use for Throttle Bodies?

Post by slingy1052 »

Hi PugMonkey,

Always good to see another Squirter on here.

What engine and TB's are we looking at here? MAP is taken from between the Throttle butterfly and the back of the valve, so dosnt matter if one butterfly or ITB's, MAP is still available.
It gives a usefull guide to engine load that TP (throttle possition) can not do on its own.

I use alpha-n with "Multiply By MAP" enabled. This gives a really easy to use comprimise of having a simple RPMxTP table (alpha-n) to work with for tuning but still getting the benefits of MAP correction , which in my case even accounts for boost as well. This is by means of the firmware multiplys whatever KPA MAP reading it sees by the value in the VE table, thus giving you a sort of live correction.
So say your cruising at 2000rpm, 8% TP, this will bring you to a curtain Bin on the table, for example , we will put a VE value of 40 in this bin.
While cruising at such a small TP we will have a low MAP value , say like 70kpa. So the fuel that goes to the injector will be 40x0.7=28
But, at another time you might be accelerating throught he same bin on the table and have near 95kpa, so here the injector will get 36 and thus the extra fuel for this situation.
It works well, and is a simmple way to get going. I am sure ITB mode yields great benefits but am yet to play with it.

So the very least you will need is
Crank angle sensor and trigger wheel (run wasted spark)
coolant sensor
air temp sensor
MAP sensor (in ECU)
O2 sensor (worth its weight in gold ;) )

With the MAP you will need a sample point from each TB. If they dont have them, then drill and tap each one and use the small mig welding tips as a nipple. these are cheap, already have a nice small hole,( i use the 0.6mm ones ) and are an M6 thread so easy to get taps for.
All 4 need to be joined together and then put a small fuel filter in the final line to the MAP to act as a damper. This gives a really stable MAP reading.
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