Speedometer Adapter

fastd · #1 (**permalink**) 10-19-2018, 09:35 AM

I'm having a difficult time getting my speedo to read correctly after a transmission upgrade.

I've changed the gear but it didn't make enough of a difference.

I know that there are gear ratio adapters that fit onto the transmission but I can't get at my trans without taking a bunch of stuff out.

Anyone know if there is an adapter or something that I could put at the speedo end of the cable to recalibrate?

Thanks.

jzervas · #2 (**permalink**) 10-19-2018, 11:34 AM

Try calling Rowland speedometer at 727-410-6352. They make ratio adapters.

cycleguy55 · #3 (**permalink**) 10-19-2018, 02:47 PM

Or fit a GPS speedometer sender and end speedo calibration forever.

jzervas · #4 (**permalink**) 10-19-2018, 02:57 PM

And a GPS speedometer as well. Not a cheap option, but a doable one. I have one on my V8 powered bug and it works well.

joyridin' · #5 (**permalink**) 10-19-2018, 04:23 PM

I put one of these in my car.

https://www.classicautoinnovations.com/classic

Works off GPS and isn't a whole lot different in price than a GPS speedo, but you can use whatever speedo you want. I had to switch the wires so it ran backwards, but that was a breeze.

HealeyRick · #6 (**permalink**) 10-19-2018, 04:49 PM

Quote:

Originally Posted by joyridin'

I put one of these in my car.

https://www.classicautoinnovations.com/classic

Works off GPS and isn't a whole lot different in price than a GPS speedo, but you can use whatever speedo you want. I had to switch the wires so it ran backwards, but that was a breeze.

I'm one of the beta testers for the Classic Speed and it really is the perfect solution for an issue like this. It's also great because if you change tire sizes or rear end ratios it will still function accurately

fastd · #7 (**permalink**) 10-19-2018, 05:16 PM

the classic speed solution looks pretty good. do you sell a short speedo cable?

joyridin' · #8 (**permalink**) 10-20-2018, 06:45 AM

Just call them up. I think they will sell you any length speedo cable you want. I mounted my unit in the trunk by the roll bar and the cable goes to the dash. Works great!

Make sure you tell them you are running a reverse speedo if you are. It takes about 5 minutes to switch the wires, but they will do it for you for free.

Gaz64 · #9 (**permalink**) 10-23-2018, 02:59 AM

Assumes a fixed speed of 30mph until satellites are found.

Don't like the sound of that AT ALL.

Next, we will have satellite braking systems, or throttle control.

joyridin' · #10 (**permalink**) 10-23-2018, 05:32 AM

No big deal. the speedo stays at 30 mph for about 10 seconds, then drops or increases to read your actual speed.

cycleguy55 · #11 (**permalink**) 10-23-2018, 02:26 PM

Quote:

Originally Posted by joyridin'

No big deal. the speedo stays at 30 mph for about 10 seconds, then drops or increases to read your actual speed.

10 seconds? That's about the amount of time it takes me to back out of my driveway. IOW, no problem.

jzervas · #12 (**permalink**) 10-23-2018, 06:12 PM

Wire up the GPS antenna so its hot all the time. Then the speedo will work the moment you drive. The GPS antenna consumes as much power as a clock. Problem solved.

Gaz64 · #13 (**permalink**) 10-23-2018, 07:32 PM

Quote:

Originally Posted by jzervas

Wire up the GPS antenna so its hot all the time. Then the speedo will work the moment you drive. The GPS antenna consumes as much power as a clock. Problem solved.

Does it work when parked in a garage or shed?

jzervas · #14 (**permalink**) 10-23-2018, 07:44 PM

On my car it does, it shows connected when parked in my shop.

Gaz64 · #15 (**permalink**) 10-23-2018, 07:48 PM

So it has a signal, when most GPS devices lose the signal?
Must be a good antenna.

jzervas · #16 (**permalink**) 10-23-2018, 08:01 PM

VDO brand, mounted on my dash.

fastd · #17 (**permalink**) 11-14-2018, 07:25 AM

I have a Smiths speedo gauge part number SN 5321-12 with a calibration number (if that's the right way to call it) of 860.

I'm told that usually ERA speedos use SN 5346-04 with a calibration number of 1000.

I'm told that these speedos can be recalibrated. Measure the number of turns the speedo cable makes over a distance of 59' 9.5" to determine how the speedo is calibrated.

Anyone have any wisdom to share on this topic?

fastd · #18 (**permalink**) 12-16-2018, 05:47 PM

To finish this little saga:
I pushed my car and the speedo rod turns 10.5x over 59' 9.5". (if I would have had a 1000' speedo in the first place instead of a 840' one, then I don't think that there would have been a problem).

I sent the speedo to Nisonger and they recalibrated the speedo and odometer gears quickly and at a reasonable cost.

Perfect now. Thanks to all.