Hennessey Stage 1 Viper Module?

[heath1225]

I was going to attempt to recalibrate the speedo box on my car (had 3.55 gears) because I now have 3.07 gears and 19" wheels. I had assumed I had a speedo box because the speedometer was accurate when I had the 3.55 and stock wheels/tires. I removed the ECM cover to find that there was no speedo box. However, I did find a label that said "Hennessey Motorsports, Stage 1 Viper Module Gen II Engine" and it had the date 9/8/98 and ED37. My question is: what does this mean? As far as a speedo box, could it be located elsewhere or is the Hennessey module able to recalibrate the speedometer by flashing it? Thanks!

 

[FrankBarba]

Call Hennessey. do a g00gle

 

[heath1225]

Called Hennessey. Did you really think they would be of help? Haha

 

[speedracervr4]

No other part #s on the PCM? my guess would be it's probably just a sticker. Not sure on where else the speedo box would be.

 

[steve e]

On my 99 GTS the speedo box piggy backs off the gray and white wire off the ECU, its some where in that area. Once you remove the speedo recal box from the gray wire the factory ECU will work right for the stock 3:08s.

 

[heath1225]

There is a white sticker with numbers on it. I see what it says.

I know the speedo box should be off those wires, but there is nothing there.

 

[steve e]

Maybe Hennessey does the speedo calibration in the ECU, Stage 1 Module= 3:55 gears calibration. He does not use the add on cal box.

 

[heath1225]

I was told you could not recalibrate through the ecu on Gen 2 Vipers.

 

[FrankBarba]

What a guy. Did the original work on the car & now will not help with troubleshooting at the least?
Guess he is too busy with his other projects.

 

[heath1225]

Frank- I told them my situation. I just wanted info on the Module. "Sorry. Can't help you" was the response. No effort. I mean, surely someone there would remember what it was.

 

[Allan]

Hmm, Gen II Vipers should be using some form of Chrysler SBEC controller if I'm not mistaken.
If I remember correctly, The SBEC has a function that can be accessed with a scan tool to change the parameter for speedo calibration.
It's called 'pinion factor' in the menu.

Been a long time since I have been fumbling around in an older Chrysler PCM looking at stuff like that, so I may be way off base here.
But it might be worth looking into finding someone with a full-function scan tool (not a code puller), to see if that can be done.

Seems like that ability was available on the trucks and minivans for different tire sizes, and gears for the trucks.
I may be mistaken on this one though.........

just trying to be of help.

 

[Allan]

It's the gen I Vipers that require the speedo calibration box outside the pcm, right?
Those were Chrysler SMEC.
SMEC had no access to change anything via scan tool.

 

[Paul Hawker]

Might contact Devin at Unitrax in SoCal. He has done tons of gear ratio changes, and might be able to guide you on how to get your spedo to read right. (714) 630-4327

 

[klamathpro]

When you do find it, I'll buy it off you. Do you still have the 3.55 gears too? I'll buy them if yours are still good.

 

[heath1225]

klamathpro- actually its broke. That's why I replaced it. Sorry.

 

[Sybil TF]

Hmm, Gen II Vipers should be using some form of Chrysler SBEC controller if I'm not mistaken.
If I remember correctly, The SBEC has a function that can be accessed with a scan tool to change the parameter for speedo calibration.
It's called 'pinion factor' in the menu.

Been a long time since I have been fumbling around in an older Chrysler PCM looking at stuff like that, so I may be way off base here.
But it might be worth looking into finding someone with a full-function scan tool (not a code puller), to see if that can be done.

Seems like that ability was available on the trucks and minivans for different tire sizes, and gears for the trucks.
I may be mistaken on this one though.........

just trying to be of help.

Can anyone conform this? I need something on my 96GTS for it has 3:73 gears. If I can correct speedo without a box that would be great.

 

[heath1225]

^ yes. I would love to not use a speedo box.

 

[Allan]

Can anyone conform this? I need something on my 96GTS for it has 3:73 gears. If I can correct speedo without a box that would be great.

I hope I'm not throwing out a false *** of gold at the end of the rainbow. It's just that 96 and later Chrysler PCM's allowed a few special functions with oem or higher end scan tools. Weather the Viper platform has these 'variable parameters' or not, I don't know.
The only way to know for sure is to just plug in and see what the PCM/scan tool will or won't do.
Or, someone who has looked into this specifically will chime in, verify that I'm either correct, or an idiot.

On my gen III, I have access to everything except the 'chassis system' -which is where the TPMS programming is.
Requires a Chrysler DRB-III or a WI-Tech scan tool to do that.
I do have access to 'chassis system' on other Chrysler vehicles, just not the ZB platform (Viper).

I 'm sorry I don't have the real answer here, I don't have any gen II Vipers around to try. I work on regular cars/trucks.
Hopefully you guys can get the correct info about this.

If the Viper parts vendors are selling a 'calibration box' for gen II,... more than likely I am an idiot, and apologize for wasting your time.