vss + electronic speedo + atlas solution?

[tdc_worm]

what is a solution for getting the VSS to work appropriately on an EFI swap, using an Atlas 4spd xfer case, and an electronic speedo (Autometer Cobalt).

Here are my specs:
5.8L
700r4
Atlas 4spd

If have read that a VSS is not mandatory for an A9L/automatic application. So if I eliminate the VSS because of the atlas, where do I get my signal from for an electronic speedo? I am sure I have over thought this...

 

[Broncobowsher]

You will need a VSS for the speedometer you selected to work. Only way to get speed without VSS is GPS.

I hope you can still change the order for the Atlas for them to install the VSS. Now if you hook the EEC to it or not is up to you. But since you will already have a VSS for the speedo to work, might as well hook it to the EEC as well.

Short answer; no VSS, no speedo.

 

[tdc_worm]

You will need a VSS for the speedometer you selected to work. Only way to get speed without VSS is GPS.

I hope you can still change the order for the Atlas for them to install the VSS. Now if you hook the EEC to it or not is up to you. But since you will already have a VSS for the speedo to work, might as well hook it to the EEC as well.

Short answer; no VSS, no speedo.

actually, a little more digging indicates otherwise. i remembered reading something about a hall effect sensor in dave's thread about the VSS and OBDII in his application. it appears that Autometer as already thought of this for us...they make part number
--5291 to work w/ gm and chrysler apps
--5292 works w/ ford apps.

i just wonder if either one of those will work w/ a standard atlas 4spd tailhousing which appears to be made for a jeep (of some unknown year) type speedometer...

 

[Broncobowsher]

Those parts are a VSS. Just mounted in line on a cable instead of directly onto the transfer case. Those would mean even more parts (adding a spedo cable) and probably even more money then just getting the Atlas with a VSS to begin with.

 

[tdc_worm]

Those parts are a VSS. Just mounted in line on a cable instead of directly onto the transfer case. Those would mean even more parts (adding a spedo cable) and probably even more money then just getting the Atlas with a VSS to begin with.

okay, i am picking up what you are putting down---they do seem like their own little vss. according the installation manuals for both the Summit and Autometer versions the sender replaces the cable...it is plugged into the tranny/xfercase on one end, w/ a capped provision on the other end should you decide to use cruise control. the way i read the instructions, it shows the hall effect sensor plugging directly in, before a speedo cable would. not trying to argue w/ you here, but the way i read the instructions, i am get conflicting info....

after a little more digging, the Atlas 4spd manual (p20) states that the standard case accepts a stock speedometer from a 1997 or newer Jeep. that should indicate that the hall effect sensor to drive an electrical speedo would be autometer pn 5291 which is roughly $60.

As far as the VSS, I would prefer to run it, but my research indicates that the stalling issue is only associated w/ manual trannies. For the atlas, I have found no information that indicates that their VSS tailhousing option is compatible w/ a ford VSS...they only mention GM. The GM and Ford VSS both use different signal waves and PPMs, which could potentially confuse the computer. so it sounds like i am SOL on running a VSS w/ an atlas unless I spring for This dakota digital signal interface, which seems like a waste of cash at this point...

 

[av8rds]

mmmm dont have time to look it up right now but I bought a VSS set up from Novak. The tone ring bolts to the output shaft of the tranny. I had to drill and tap a hole in the tailshaft for the sensor to screw into. It was the only way I could make it work with the FAST system at the time.

 

[76 bronco J]

>>>>> I've been wondering for future EFI about the necessity of running the VSS sensor & have also noticed they say automatics are alright without it ,but have also noticed Ford Racings new one piece harness doesn't even have the capability to run one......... so I'm wondering why Ford didn't think it was necessary & Ryan states this is one of the faults of the new harness..... the M-12071-A50 Ford harness looks really good to me , it has a new compact relay box with green LED power indicators that mounts inside & looks to have more length to mount the computer with the plug down(correct way) on the kick panel than Ryans harness >>> http://fordfuelinjection.com/files/M-12071-A50.pdf ....... edit >> here's a website I found with a Ford Racing parts dealer offering parts for 10% over cost & the new Ford harness for $467.50..... http://www.modularfords.com/forums/showthread.php?p=1274217

 

[Dave]

The older Ford VSS is a variable reluctance sensor. (Magnet passing by a coil) It's a 2 wire analog signal that the PCM (A9L) processes. The newer stuff, especailly those getting the VSS from the ABS system and distributing it to several devices like the PCM, stereo, speedometer, cruise control, etc use a digital pulse from the VSS source. A hall effect sensor generates a compatable signal. It is a powered device that has 3 wires (+12v - gnd - and vehicle speed signal). It's not compatable with the A9L. The variable reluctance sensor is not compatable with the electronic speedos etc... Thus the interface device. I would get the atlas with the spedometer cable option and stick one of the varaible reluctance VSS on the back of the speedometer if you want or need to provide that to the PCM. Ford uses 8 pulses per revolution on both the older and newer stuff. That translates to 8000 pulses per minute at 60 MPH. Calculate the correct speedo drive gear for your gearing and tire size before you order the Atlas. I wrote up a bunch of babble about it on my OBD II thread.

http://classicbroncos.com/forums/showthread.php?t=124065&page=3

http://classicbroncos.com/forums/showpost.php?p=1255159&postcount=67

 

[tdc_worm]

The older Ford VSS is a variable reluctance sensor. (Magnet passing by a coil) It's a 2 wire analog signal that the PCM (A9L) processes. The newer stuff, especailly those getting the VSS from the ABS system and distributing it to several devices like the PCM, stereo, speedometer, cruise control, etc use a digital pulse from the VSS source. A hall effect sensor generates a compatable signal. It is a powered device that has 3 wires (+12v - gnd - and vehicle speed signal). It's not compatable with the A9L. The variable reluctance sensor is not compatable with the electronic speedos etc... Thus the interface device. I would get the atlas with the spedometer cable option and stick one of the varaible reluctance VSS on the back of the speedometer if you want or need to provide that to the PCM. Ford uses 8 pulses per revolution on both the older and newer stuff. That translates to 8000 pulses per minute at 60 MPH. Calculate the correct speedo drive gear for your gearing and tire size before you order the Atlas. I wrote up a bunch of babble about it on my OBD II thread.

http://classicbroncos.com/forums/showthread.php?t=124065&page=3

http://classicbroncos.com/forums/showpost.php?p=1255159&postcount=67

That was the route I was heading down...stick w/ the standard atlas w/ mechanical speedo option, run the Autometer hall effect sensor for the electronic speedo and see how it does. I am not sure what you mean when you sugges running the variable reluctance VSS on the back of the speedo. Care to elaborate?

 

[Dave]

That was the route I was heading down...stick w/ the standard atlas w/ mechanical speedo option, run the Autometer hall effect sensor for the electronic speedo and see how it does. I am not sure what you mean when you sugges running the variable reluctance VSS on the back of the speedo. Care to elaborate?

If you are going to run an electronic speedometer you wouldn't need to run a speedometer cable. Just get the Atlas with the hall effect (digital). The A9L PCM is not compatable with the (digital) signal. It will only work with a VR (analog) sensor. Are you going to run both a mechanical speedometer and an electronic speedometer? I guess what I'm trying to say is that if you want to provide the PCM with a VSS you will have to drive a VR VSS somewhere in the system. You can get one that screws on to the speedometer drive input and the speedometer cable screws in it.

 

[tdc_worm]

If you are going to run an electronic speedometer you wouldn't need to run a speedometer cable. Just get the Atlas with the hall effect (digital). The A9L PCM is not compatable with the (digital) signal. It will only work with a VR (analog) sensor. Are you going to run both a mechanical speedometer and an electronic speedometer? I guess what I'm trying to say is that if you want to provide the PCM with a VSS you will have to drive a VR VSS somewhere in the system. You can get one that screws on to the speedometer drive input and the speedometer cable screws in it.

nope, just a an electric speedo. so if I understand you correctly, I need a VR VSS pluged into a mechanical speedo type input. Could I then piggy back my electrical speedometer on the VSS via hall effect sensor or otherwise? I dont see why not.

 

[Broncobowsher]

nope, just a an electric speedo. so if I understand you correctly, I need a VR VSS pluged into a mechanical speedo type input. Could I then piggy back my electrical speedometer on the VSS via hall effect sensor or otherwise? I dont see why not.

That sounds right to me.

It is surprising how little the eletronics care about the signal. Square or sine wave, most of them will accept just about anything you give them.

 

[toddz69]

what is a solution for getting the VSS to work appropriately on an EFI swap, using an Atlas 4spd xfer case, and an electronic speedo (Autometer Cobalt).

Here are my specs:
5.8L
700r4
Atlas 4spd

If have read that a VSS is not mandatory for an A9L/automatic application. So if I eliminate the VSS because of the atlas, where do I get my signal from for an electronic speedo? I am sure I have over thought this...

Will one of the Wild Horses options work for your electronic speedo?

http://www.wildhorses4x4.com/product/Atlas_Speedometer_Combo/Atlas_Transfer_Case

Todd Z.