Click here to return to the home page.
Classic Morgans
Who's Online Now
6 members (Deejay, Steve +8, +8Rich, Image, Morganmike, Alan Patterson), 248 guests, and 46 robots.
Key: Admin, Global Mod, Mod
Top Posters(30 Days)
+8Rich 88
Luddite 50
Newest Members
Carbuilder, Scot_SJI, Jimmers, Breen60, Davidmog
9,597 Registered Users
Newest Topics
morgan supersport 357 miles
by Nick_H - 09/09/26 09:13 PM
M3W Treffen 2027
by Laurens - 09/09/26 08:12 PM
Changing the Colour of a Tonneau Cover..
by flyfisher - 09/09/26 06:33 PM
To our Norwegian friends
by bmgermany - 09/09/26 05:14 PM
2017 4/4 two seater storm cover new unused £95
by simon8201 - 09/09/26 01:46 PM
radiator fan
by riri - 08/09/26 09:20 PM
Luggage rack alternatives - Revo Rack
by Haggispeed - 08/09/26 04:19 PM
Latest Photos
1989 Morgan Plus 4 in Ontario, Canada
1989 Morgan Plus 4 in Ontario, Canada
by Carbuilder, September 5
First anniversary of Plus 4
First anniversary of Plus 4
by Strathaven, September 5
Wales
Wales
by Joske Vermeule, September 1
Engine/Gearbox Separator CX Models
Engine/Gearbox Separator CX Models
by number thirteen, August 30
tow bar
tow bar
by G Walker, August 24
Forum Statistics
Forums39
Topics49,896
Posts837,956
Members9,597
Most Online1,063
Jun 14th, 2026
Today's Birthdays
Bobajobbob, HeadlessBlue, Lester247, RicHardy
Previous Thread
Next Thread
Print Thread
Page 4 of 9 1 2 3 4 5 6 7 8 9
Joined: Jun 2015
Posts: 2,095
Likes: 75
Talk Morgan Expert
Online Content
Talk Morgan Expert
Joined: Jun 2015
Posts: 2,095
Likes: 75
on a plus 4, the speedo can be recalibrated. Keep the trip recorder button under the dash depressed whilst starting the engine and a code will appear in the mileometer. as each digit flashes, it can be changed by multiple presses of the reset button and will finally revert to normal mileage reading. think a plus 4 was something like 008386, but guess codes vary for different models. Don’t know how much the number needs to be changed to achieve a significant alteration though but others might?
Also, if the speedo is difficult to read with tonneau in place, why not swap positions of rev counter and speedo. (unless you are always driving to the red line!) I am told that the wiring is usually long enough to do that.


Doug
2011 Plus 4 in Rich Maroon

1972 750 “ComDom” sprinter
1958 Triton 650
1992 Triumph Trophy 900
Joined: Dec 2008
Posts: 22,370
Likes: 354
Roadster Guru
Member of the Inner Circle
Offline
Roadster Guru
Member of the Inner Circle
Joined: Dec 2008
Posts: 22,370
Likes: 354


DaveW
'05 Red Roadster S1
'16 Yellow (Not the only) Narrow AR GDI Plus 4
Joined: Jul 2007
Posts: 27,831
Likes: 757
John V6 Offline OP
Member of the Inner Circle
OP Offline
Member of the Inner Circle
Joined: Jul 2007
Posts: 27,831
Likes: 757
The Mustang forum suggests reflashing the PCM. I will let Bell & Covill figure that out with MMC as they sold me an illegal car.
Meanwhile I have a cheap GPS speedo to help


JohnV6
2022 CX Plus Four
2025 Renault Scenic Alpine etech "Yvette"
Joined: Jun 2020
Posts: 84
S
Just Getting Started
Offline
Just Getting Started
S
Joined: Jun 2020
Posts: 84
I purchased a sat nav for touring around Cornwall, the added benefit being it had a speedo, although as stated earlier, I am not wholly convinced it is accurate - going by road side speed warning displays.

It is also a bit too much hassle for every day trips.

I did think about adding a digital readout that connected to the ODB port, is this worth it though? Would the data from the ODB port be more accurate?

Appreciate any guidance.

Steve

Joined: Apr 2014
Posts: 5,182
Likes: 2
Ray Offline
Charter Member
Offline
Charter Member
Joined: Apr 2014
Posts: 5,182
Likes: 2
My tom tom seems to match closely with my speedo and most roadside signs.


.+8 Now gone for a 1800 4/4. Duratec in bright yellow.
Joined: Dec 2009
Posts: 37,472
Likes: 988
Tricky Dicky
Member of the Inner Circle
Online Content
Tricky Dicky
Member of the Inner Circle
Joined: Dec 2009
Posts: 37,472
Likes: 988
I totally rely on my Tomtom and find it shows all three cars to be over reading by + 5mph, the variable Motorway speed limits agree with it so I'm assuming it's pretty accurate.
It's kept me safe from the revenue collectors since 1991 so somethings working, the best £90 I ever spent.


2009 4/4 Sport Henrietta
1999 Indigo Blue +8
2009 4/4 Sport Green prev
1993 Con Green +8 prev





Joined: Feb 2016
Posts: 8,695
Likes: 415
Needs to Get Out More!
Offline
Needs to Get Out More!
Joined: Feb 2016
Posts: 8,695
Likes: 415
Adrian's thread on the PCM (ECU) development leading to the one you have John is here. You will note there is specific reference to trip and speedometer anomalies!


Richard

2018 Roadster 3.7
1966 Land Rover S2a 88
2024 Royal Enfield Guerrilla 450
1945 Guzzi Airone
Joined: Aug 2010
Posts: 5,468
Likes: 172
Charter Member
Offline
Charter Member
Joined: Aug 2010
Posts: 5,468
Likes: 172
I have a GPS Speedo on the steering column. It agrees with roadside signs all the time and reads around the same as the speedo.

If you use self adhesive velcro on the steering column behind the dashboard and fabricate a bracket from an old tupperware box, you can make quite a neat unobtrusive fastening that is easy to remove when the time comes for the car to be sold. I power it from a USB socket fitted in the radio blanking plate.


Paul
Costock, UK
Plus Four 75th - Furka Rouge - Pip
Disco 5
Teddy - 17h1 Irish Draught cross
Joined: Nov 2015
Posts: 8,692
Likes: 498
Just barreling along
Needs to Get Out More!
Offline
Just barreling along
Needs to Get Out More!
Joined: Nov 2015
Posts: 8,692
Likes: 498
Originally Posted by StevieMac
I purchased a sat nav for touring around Cornwall, the added benefit being it had a speedo, although as stated earlier, I am not wholly convinced it is accurate - going by road side speed warning displays.

It is also a bit too much hassle for every day trips.

I did think about adding a digital readout that connected to the ODB port, is this worth it though? Would the data from the ODB port be more accurate?

Appreciate any guidance.

Steve



Steve, that's what mine is, if you look earlier in the tread there's some photos


Jon M
Joined: Jun 2020
Posts: 84
S
Just Getting Started
Offline
Just Getting Started
S
Joined: Jun 2020
Posts: 84
Originally Posted by CooperMan
Originally Posted by StevieMac
I purchased a sat nav for touring around Cornwall, the added benefit being it had a speedo, although as stated earlier, I am not wholly convinced it is accurate - going by road side speed warning displays.

It is also a bit too much hassle for every day trips.

I did think about adding a digital readout that connected to the ODB port, is this worth it though? Would the data from the ODB port be more accurate?

Appreciate any guidance.

Steve



Steve, that's what mine is, if you look earlier in the tread there's some photos


Cheers for the pointer Jon.

I was looking at something similar on the web before I went the Sat Nav route but that does look a little simpler,

How visible is the readout in bright light?

Steve

Page 4 of 9 1 2 3 4 5 6 7 8 9

Moderated by  TalkMorgan 

Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5