Installed the Wells TPS

I had some time today, so I installed the new Wells TPS. I had to change the wires around as the previous TPS had a CCW rotation or was it CW, depends on which side you look from I suppose.

Anyway, it is a little ripper, once I calibrated it to the MegaSquirt, it went from 0% to 100% and was completely repeatable. No more couple percent variation like I had from all of the previous TPS’s! Yeah!

Hopefully this will be the last I have to do with TPS’s for a long while.


3 Replies to “Installed the Wells TPS”

  1. Hi Jim

    I noticed you were using an SU carb as a Throttle body and was wondering how you connected the TPS to it? I basically want to get some readouts from the carb so that tuning and also diagnosing issues would be easier.

    I also have been wanting to be able to measure the amount the needle goes up on the carby when under load. I know this isn’t related to your EFI conversion but I was wondering if you had any idea on how to put a sensor, I’m guessing it will have to be analogue as there will be more than 2 positions the needle will be at. I’ve seen it done once in a website a while back but haven’t been able to find it since and the website didn’t have any instructions anyway.

    Any feedback would be valued greatly.



  2. Hi Roshane,

    The TPS is attached via a custom bracket that came with SU HIF44 EFI adaptor I bought from Patton Machinery. ( 4) I ultimately ditched the resistive TPS’s and used a replacement Hall Effect one from Well Electronics ( I believe most of Well’s TPS’s are now Hall Effect, but get from supplier that has or can confirm that the TPS’s is a Hall Effect.

    What I’d look at, this is just quickly of my head mind you, is using a vertical flat bar with 4 bit Gray code ( printed on it. You would have to fashion 4 LED sensors or similar and a light source, to detect the position of the piston/needle assembly. The 4 bits would coincide with the 16 needle positions. Going 5 Bits would give 32 positions, offering better resolution. As I said I haven’t tried this, just an idea.

    I have read of someone talking/doing a video of a stick attached to the piston assembly, but I feel that it would be hard work. On your web site, you mention that you’re a mechanical engineer, so maybe if you machined a sensor assembly that fits into the top or around the top of the SU, it would contain the sensors and a ‘slot or space’ that allows the graduated ‘Gray code’ stick to go up and down in it.



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