Jump to content
SAU Community

Recommended Posts

I'm running a Motec M4 ecu on my RB26 in a S13 200sx and I'm trying to get the tacho to work. I'm using a R32 GTR tacho. I've set up the ECU so one of the AUX outputs is set to the tacho signal. I hooked up a multimeter to this wire and I get a RPM / 10000 signal (ie, 800rpm = 0.08 volts) which I've since found out from other theads that the tacho doesn't use this type of signal.

Is there anything I can do to change this signal so the tacho can read it? Or can I use another signal from the ECU that the tacho can use?

Link to comment
https://www.sau.com.au/forums/topic/69143-hooking-up-tacho-to-motec-m4-ecu/
Share on other sites

Most tacho's use frequency to drive them. i.e a fixed duty cycle of 50% and the frequency increases proportionaly with revs. I don't know about the Motec, but my Haltech has a tacho aux. output. You set the "pull-up" value and duty cycle to 50% in the software, and your done. Maybe double check the Motec for this type of output?

RB30-POWER, the current switchover points are on at 1500 and off at 4250. 'Seat-of-pants' testing suggested a slightly lower switch off point than 4500, but i haven't backed this up with dyno testing. Also, the position of my cam belt tensioners didn't allow the cams to line up correctly, so from memory they are both advanced about 5-7 crank degrees. Me thinks some adjustable gears will be going in shortly.

Sorry bout the hijack Robert_NZ....

Cheers, yeah it makes sense that the switchoff point would be lower on the larger 3L motor. It would be taking the same air as the rb25det but much lower in the rpm range. With the stock cams anyway.

Also i think the VCT side cam gear could be adjusted by the four bolts on the rear of the gear. Might get that 5 or so degrees back to standard.

I have heard of people adjusting the VCT gear by this method with great results, but i don't know if the adjustment is for that purpose, or wether its to adjust the actual operation of the cam gear mechanism itself.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Seat of the pants assessment of the new intake: The car is way less "doughy" when hitting the loud pedal, especially off idle when stopped or in traffic, I did use a cheapo lazer thermal thingo to measure the temp around where the pod filter got its air, it was between 55 - 60°C, in saying this the car was shut off and not moving, so the OEM intake pipe was not supplying any fresh air to where the pod was when the car was at least moving A weird bonus was induction noise on the throttle in the cabin increased a bit,  I was worried that I was actually going to lose some of that induction noise I love so much, outside though, when I got the daughter to do a WOT drive by pass for me, the induction noise has increased alot when on the throttle, not quite ITB doort, but well up there I'm extremely happy with the results and have been exploring the country roads in the region  As for house mods: 1.New front fence is up and is awesome, it really upgraded how the joint looks from the street, and the added security is nice 2. Electricians have replace some interior lights, and with more lighting in the garage, a few new motion detecting lights out the front above the garage, front room, and at the front door, which I have already found heaps helpful coming and going, also now has fancy pants CCTV all round the house The only hold point for power though is the solar and batteries due to supply issues, although this will happen over the next few weeks 3. I have done a heap of landscaping out the front and I'm almost ready to do a new small retaining wall with some nice blocks to replace the brick and cemented in rocks around the raised garden beds cemented in river stone "was the fashion at the time" the house was built. I currently have a pallet of retaining wall blocks and 2 bulka bags of 20mm blue metal to replace the wood chip that is in the raised garden beds around the house 4. I now have 3 big raised garden beds for out the back to grow some vegetables, about 70cm high, 200cm long and 100cm wide 5. My 2 compost bins are already pretty full with brown, green and kitchen waste from the landscaping I'vedone so far, but they will probably take a few months to break down, so anything else that gets chopped, trimmed, and kitchen waste will just start filling the base of the raised garden beds to about 30cm before I start throwing 40cm of good compost, and stuff, for the vegetables to grow in, I'll need a few ton of compost and soil, but the local supplier can sent me bulka bags of the stuff Basically the logs, wood chips and a few strategically placed rocks for drainage, will give the beds some good organic materials down low to break down over time, and they will hold moisture during the warmer months to save the water in my big arse water tank if we don't get alot of rain So, all in all, the car and house mods are going well, and I'm really enjoying being retired, I sleep in too 0700 and slowly plod around inside until I feel like actually doing anything, and only work in the yard for as long as want, which has actually been alot over the last few weeks,  although when you look at it, it seems that not a huge amount of work has been done,  until I look at the before I started the work pics Happy days and good times indeed 
    • hahaha yeah. Plan is to get side skirts and probably just rear pods. But going to do them one-by-one. I've got a set that I really like from RHDJapen, but that one isn't shipped to AU. So need to find someone who can get it for me
    • Here's an idea, answer the questions I asked you as they are trying to work out WHY the LSD will be binding up in a straight line.
    • You haven't driven many modern cars then have you? Most of them have sfa steering feel with their stupid electric bullshit steering systems.
×
×
  • Create New...