Just curious, Can we use an aftermarket TPS say if we want to use a different throttle body or ITBs instead of trying to mount the factory one?
Isn't it just a potentiometer and an idle switch? and i think it does WOT also?

 

Give this a read-

http://www.arnnworx.com/catalog/inde...id=2&chapter=1

 

This is from the Arnnworx writeup on the TPS:

http://www.arnnworx.com/images/TPS-schmatic.jpg

As you can see it has a potentiometer for position, as well as the 2 contact switches (idle, WOT) like what you see in an NA TPS.

As far as aftermarket, no reason why not - as long as you have a way of tuning your ECU to correlate the potentiometer range to the throttle position range. Many other parts mechanically bolt up but a stock DME would have invalid potentiometer readings because the resistances are probably going to be different. I'm running a 951 TPS on my NA for my standalone, and also using a 951 TPS on my buddie's E30 when we put Megasquirt in that car. It's just a matter of calibrating it in the software. Many BMW and Audi parts also will work. For a standalone, usually you just use the potentiometer and not the contact switches, idk what you're using for an ECU.

 

The 951 TPS just has one switch (for idle) and a potentiometer to measure the throttle angle. When the KLR sees the throttle is open 65 degrees or more, it generates its own WOT (full load) signal, but that signal is generated by the KLR, not by a switch in the TPS. But I agree, if you can match the resistance scale of the original TPS, no reason you couldn't use an aftermarket pot and switch...

 

951 TPS has both: idle/WOT switch for DME and variable 0-5v throttle position sensor for KLR.

 

I "think" we are saying the same thing: there is only one switch, which closes at idle and open when not at idle. Second, there is one potentiometer, which the KLR uses to determine how open the throttle is. The KLR then uses the potentiometer to generate its own full load (WOT) signal when the throttle is 65 degrees open. There is no WOT switch in the TPS.

 

Thanks guys.

I was looking at throttle body options for my car and wondering if it's worth transferring one to another or if there's an option to use another.

Seems as all current ones have no switch on them.

 

You 'might' be able to setup a drive by wire with the M400. I'm pretty sure it's an Upgrade option. Can't tell you if that is unlocked on mine right at this moment. Possibly?

 

Pretty sure you can do drive by wire on it. I'll probably do it on the 924 with the awkward placement with the intake.

But this is for the 944. I was just thinking of mucking around with intakes. But there's no use with the stock TB. Then if i get a universal, just means more mucking around to make the stock one work.

Ive been playing with solidworks to much. a little excited.

 

lots of BMW/Volvo out there with switched/pot type TPS.

just have to get one with the pot values in the right range, can't imagine there's all that much variety since only 2-3 companies actually make these parts for all the car MFRs.

if you need a switch input, old VW (80s/maybe very early 1990s) had a simple switch adjusted just so to trigger their idle or WOT function (forget which) when the throttle cam was in a certain position...seems to work OK.

 

Spencer - neat hod rodding idea.
I could possibly if i really decide to play with intakes ect, to use a normal pot TPS and use a module that will switch depending on input voltage. They're about $30.