LS_1 / 280Z Speedometer Question

[rwwisnesky]

Help, I give up. I am a 60's vintage mechanical guy with a 2007 electronic question. Finally have the LS_1 with 6 speed in the 1978 280Z. Got a Abbott Cable X box for the speedometer conversion. To get it to work I need to calibrate it. It needs to know pulses per mile in order to function. Formula = Transmission # teeth X rear axle ratio X tire revs per mile equals pulses per mile. How do I find out how many teeth on the transmission gear, I can figure out the rest.

 

Thanks in advance

 

rwwisnesky@yahoo.com

[smoorenc]

Do they mean the teeth in the sending unit in the tranny? There is an article about using different color adapters (white, yellow) in the transimssion according to your rear end ratio to keep a "normal" speedometer corrrect.

[rwwisnesky]

Yes, they are looking for the number of teeth in the tranny sending unit. Checked your web site, great work. What did you do to get the speedometer working.

[smoorenc]

Thanks,

 

I am installing an Autometer electronic speedometer. So I won't be worrying about the mechanical part. I looked but I can't find the thread on the transmission adapter to show you.

[LT1-280z]

Here's some info.

 

http://www.thirdgen.org/techboard/ltx-lsx/320227-ls1-vss-pulse-92-a.html

http://www.skulte.com/T56.html

http://www.lt1swap.com/wiringharness.htm

 

Looks like the T56 is 17 Pulse per rev. However if you are using the stock PCM the speed signal from the PCM is already calibrated to 4000 Pulse Per Mile. I highly recommend using this signal and have the PCM programed for you tire size and diff ratio. This makes the speedo calibation simple = locked in at 4000 PPM. The VSS signal is required by the PCM anyway so why not use the calibrated output?

[m1noel]

Here's some info.

 

http://www.thirdgen.org/techboard/ltx-lsx/320227-ls1-vss-pulse-92-a.html

http://www.skulte.com/T56.html

http://www.lt1swap.com/wiringharness.htm

 

Looks like the T56 is 17 Pulse per rev. However if you are using the stock PCM the speed signal from the PCM is already calibrated to 4000 Pulse Per Mile. I highly recommend using this signal and have the PCM programed for you tire size and diff ratio. This makes the speedo calibation simple = locked in at 4000 PPM. The VSS signal is required by the PCM anyway so why not use the calibrated output?

 

The CableX wont work through the PCM. Use the 17 teeth number and hook the box up directly from the trans. It works great. After my initial set up I figured I was off like 12 percent, using the book I just multiplied by that 12 percent, used their settings, and bingo, right on.

MIke

[rwwisnesky]

Thanks for the inputs. I think I will do as suggested by M1Noel and go straight to the sensor on the tranny. You folks have been great and I thank you all !!!!!!

[Pop N Wood]

Get a handheld GPS to measure your actual speed, then just trial and error change the pulse count until the speedo matches the GPS.

[LT1-280z]

The CableX wont work through the PCM.

 

Good to know, who'd of thought?

 

I built my own and I designed it to work with the PCM. Maybe there is a market for it?

[Mexicola]

Hey rwwisnesky, off topic but...that is a damn fine engine compartment you got going there. You mind me asking what paint you used for that finish? Kudos on keeping it clean and tidy!

[rwwisnesky]

Thanks for the compliment Mexicola. I stripped the compartment to bare metal. The painted it with Eastwood Rust Encapsulator. After that I used Eastwood trunk paint followed with 5 coats of Eastwood clear Diamond coat. I wanted the finish to be forgiving, and so far it has worked.

[rwwisnesky]

Question to m1noel, do you recall the wire hookup colors you used to mate to the cable x from the sensor. Cant determine which is +/- from the sensor from the shop manual.

[m1noel]

Question to m1noel, do you recall the wire hookup colors you used to mate to the cable x from the sensor. Cant determine which is +/- from the sensor from the shop manual.

 

Used the vss high BU/WH for the +

Used the vss low BN/RD for the -

 

Worked great- Good luck

Mike

[rwwisnesky]

Thanks Mike for the quick response. I was hoping you would have the answer, on my way out to the garage now to hook it up!!!! I also havr the JTR radiator on order and a Ford Taurus / Mustang electric fan (4500 cfm). Was curious what fan set up you used. The fan is a two speed so you will probably see more questions when its hook up time.

[m1noel]

I used a two speed ford fan from John's, I really don't know what is was for, but it fit the JTR radiator really well. I used the leads from the pcm to trigger two relays, one for each speed on the fan. Cools really well even in 100 degree heat with the AC on.

 

And you can PM me anytime- might notice it quicker that way.

Mike

[Phantom]

Also - route the cable from the Cablex to the speedometer very carefully to avoid any binding. Mine's off a little bit and periodically it acts up on me and starts to bounce.