Adoom Posted February 18, 2021 Report Share Posted February 18, 2021 I have a G4 Red Extreme All this stuff is in a 1971 Triumph 2000. I'd like to use the ABS sensor on the output flange on a Nissan 350Z diff to provide my speed signal. I found a post that said the number of teeth means the frequency will be too high for the digital input. Could I solve that by removing some of the teeth (but still keeping them evenly spaced of course)? I also assume that there are cars with speedos that can be driven directly by the link? Are any of them common models, where I could just go to the local wreckers to find one? I want to take the guts out of one of these speedos and make it fit into a 70's Smiths gauge. I have done this before, but I used a tacho, so there is no ODO and I'd prefer to have an ODO for this one. Quote Link to comment Share on other sites More sharing options...
Confused Posted February 18, 2021 Report Share Posted February 18, 2021 I use a hall-effect sensor (this one to be exact) that picks up on the heads of the 4 bolts that attach the propshaft to the diff, which only requires a small bracket to be fabricated to hold it to the diff carrier. The same company also have a nice "period looking" electronic speedo, which doesn't look out of place in my 1967 Ford Anglia 105E. Quote Link to comment Share on other sites More sharing options...
Adoom Posted February 18, 2021 Author Report Share Posted February 18, 2021 I forgot to mention that I am in NZ, so shipping, exchange rate and tax make those nice looking aftermarket speedos pretty damn expensive. I'm also cheap, but I would actually enjoy trying to cobble together a hybrid speedo. That hall effect sensor could be an alternative option if the ABS sensor turns out to be impossible. But the ABS sensor sure does look tidy and compact and it already has a mounting hole. Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 18, 2021 Report Share Posted February 18, 2021 The 350Z abs sensor Im pretty sure is a magnetoresistive type so will be a major ball ache to make it work. Usually you can make them work but you have to experiment a lot with different voltage supplies, pull-ups, pull-downs etc. Adoom 1 Quote Link to comment Share on other sites More sharing options...
Adoom Posted February 18, 2021 Author Report Share Posted February 18, 2021 So has anyone got any suggestions for OEM speedos that just work, directly with an Aux out? Surely they exist... Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 18, 2021 Report Share Posted February 18, 2021 It is hard to answer that one as in most oem applications they are not connected to the ecu. Typically they get their signal from the abs unit or gearbox sensor. So it would really only be guys that have done something similar to you or engine swaps that would be able to say. However I would expect most electronic speedos will be fine. It will be better to use one that had a 3 wire (hall effect) speed sensor as that will be easier to replicate by the ecu. One that used a VR sensor will need a small circuit to make the aux output signal look like AC. I know a few guys have got Nissan skyline/sylvia (VR/AC signal) ones working direct from ECU with help of a small circuit I drew. Quote Link to comment Share on other sites More sharing options...
Adoom Posted February 18, 2021 Author Report Share Posted February 18, 2021 4 minutes ago, Adamw said: It is hard to answer that one as in most oem applications they are not connected to the ecu. Typically they get their signal from the abs unit or gearbox sensor. So it would really only be guys that have done something similar to you or engine swaps that would be able to say. However I would expect most electronic speedos will be fine. It will be better to use one that had a 3 wire (hall effect) speed sensor as that will be easier to replicate by the ecu. One that used a VR sensor will need a small circuit to make the aux output signal look like AC. I know a few guys have got Nissan skyline/sylvia (VR/AC signal) ones working direct from ECU with help of a small circuit I drew. Okay, I'll see if I can find something suitable at the wreckers. I have seen your post with that circuit. Quote Link to comment Share on other sites More sharing options...
Adoom Posted February 25, 2021 Author Report Share Posted February 25, 2021 So I've borrowed the speedo off my Honda motorbike. I have it connected to Aux 5 and set it to Test (PWM). The needle does move. If I set it to 100Hz I get 10KPH, 200Hz 20KPH, 300Hz 30KPH. But then I've maxed out the Hertz so the needle doesn't move any further. Any idea? Or does this speedo really need up to 2600Hz for a full sweep? Quote Link to comment Share on other sites More sharing options...
Adoom Posted February 25, 2021 Author Report Share Posted February 25, 2021 Oh, never mind, I realised that Aux 5 can only do 300Hz, but Aux 1 can do 4000. So I'm sorted. Quote Link to comment Share on other sites More sharing options...
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