LS swap with a trans with no VSS, solutions?

[Vicinity]

I've finished my build (aside from driveshaft) and I've read conflicting reports as to whether the PCM requires a VSS signal. My Gen 3 Viper T56 doesn't have a vss (Viper used wheel speed sensor), so right now, I don't have anyway of hooking up a signal.

I'm curious as to whether anyone has had this issue and what they might have done to fix it.

Right now I'm just planning on using the GPS speedo on my phone, but I'd like a more permanent solution.

[jlcustomz]

There are speedometer output adapters to run a vss only or vss & cable. Somebody like Howell should have them. My experience on an older tuned port engine was that the vss input helped driveability, not dying when stopping, etc.

[dontlifttoshift]

The viper trans doesn't have a vss output.....at all. Dodge used a wheel sensor to run the speedo.

The engine should run fine without it being a manual trans and all.

What kind of gauges do you have? Classic Instruments and Autometer both have GPS drives for aftermarket electric speedometers.

[Vicinity]

I had all Autometer gauges, but I removed the speedo because it was a cable driven one.

The dying when stopping is the thing that I'm worried about. That sounds VERY annoying.

[parsonsj]

GPS Speedomoter:

http://www.ampcustomshop.com/gear/220/9197/

[LUV2XLR8]

yup.. GPS speedo.. plenty of companies are making them now

[garys 68]

I had the dying issue without VSS on a Richmond install. But that had a mechanical output that I used a Dakota Digital inline. The DD inline does not put out enough pulses for DBW cruise control though. So on my LSx/T10 I drilled and tapped the case over the reverse gear and used the 39 tooth reverse gear as a reluctor. I used a threaded blind VSS from Magnetic Sensor Corp. Works greast. I have pics if you want them.
Jags that Run sells a differential yoke mounted reluctor/VSS. But it's for an S10 rear end.
There's a guy over on LS1tech with a boat he wanted VSS hooked to the ecu. He used a GPS with a pulse output. Dakota digital make a pulse to sine wave converter. Sounds like it worked.
http://ls1tech.com/forums/conversion...d-options.html

[Vicinity]

GPS with a pulse output is an idea, but I'm afraid of using GPS for blind spots.

I see Dakota Digital offers a drive shaft mounted magnetic pickup, I might try that out.

[garys 68]

I havn't seen the DD setup, got a link or part number?

GPS with a pulse output is an idea, but I'm afraid of using GPS for blind spots.

I see Dakota Digital offers a drive shaft mounted magnetic pickup, I might try that out.

[BonzoHansen]

GPS with a pulse output is an idea, but I'm afraid of using GPS for blind spots.

I see Dakota Digital offers a drive shaft mounted magnetic pickup, I might try that out.

blind spot? i have a speedhut gps speedo, works good.

[Vicinity]

I havn't seen the DD setup, got a link or part number?

http://www.dakotadigital.com/index.c...109/prd109.htm

SEN-4165

Bottom most item on the page.

[garys 68]

I would be interested to hear how well it works. My experience with VSS is that they're sensitive to reluctor speed and distance.Thr GM ecu does need a minimum voltage to read speed. Not sure if that's close to DD specs. Driveshafts have a bad habit of moving in all directions. The Jags that run system mounts everything to the differential to eliminate this. I think it's set up for a 1310 u joint yoke though.

http://www.dakotadigital.com/index.c...109/prd109.htm

SEN-4165

Bottom most item on the page.

[Vicinity]

I don't think the sensor is mounted to the driveshaft, I think the sensor is hung from the floor and you attach magnetic pickups to the driveshaft.

I might try the dd option if I have stalling issues.

[Chevy406]

I tuned the GM ECM in my '69 Nova conversion to run just fine without a VSS signal. I don't have any idle problems or engine dying. However, I do plan to add a signal with a Dakota Digital "pass-through" pickup that will work with the cable drive from my TH-400. Then I can data log mph using my HP Tuners.

With that being said, you shouldn't have any problem getting your car to run just fine without a VSS signal to the ECM.

[garys 68]

The stalling happens with manual transmissions. It's typically when you're in OD, you press the clutch in and coast down from highway speeds.
As for the driveshaft mounted one, I'm sure the sensor is mounted on the car, the driveshaft acts as the reluctor. The voltage output of the vss is dependent on the vss design, driveshaft (reluctor) distance and speed. If the driveshaft moves that voltage will vary and might not be adequate for thr GM ecu to read.

I tuned the GM ECM in my '69 Nova conversion to run just fine without a VSS signal. I don't have any idle problems or engine dying. However, I do plan to add a signal with a Dakota Digital "pass-through" pickup that will work with the cable drive from my TH-400. Then I can data log mph using my HP Tuners.

With that being said, you shouldn't have any problem getting your car to run just fine without a VSS signal to the ECM.

[monkey-leader]

I had the dying issue without VSS on a Richmond install. But that had a mechanical output that I used a Dakota Digital inline. The DD inline does not put out enough pulses for DBW cruise control though. So on my LSx/T10 I drilled and tapped the case over the reverse gear and used the 39 tooth reverse gear as a reluctor. I used a threaded blind VSS from Magnetic Sensor Corp. Works greast. I have pics if you want them.
Jags that Run sells a differential yoke mounted reluctor/VSS. But it's for an S10 rear end.
There's a guy over on LS1tech with a boat he wanted VSS hooked to the ecu. He used a GPS with a pulse output. Dakota digital make a pulse to sine wave converter. Sounds like it worked.
http://ls1tech.com/forums/conversion...d-options.html

I would be interested in seeing pictures of your vss set up.