MGB V8 
Speedometer
Updated 6/24/01
www.geocities.com/V8mgb

Purchased a speedometer cable and ratio adapter from

ACI Engineering
6728 Lovers Lane
Portage, MI 49002
616-327-1991

Sent my original cable to ACI Engineering. They built be a new cable which allowed me to connect my original speedometer to a right angle ratio adapter and then to the transmission (GM Borg Warner T5).
Below is the cost break down of the system and a picture.

How I got started was I talked to Tom at ACT Engineering. He had me send my old MG speedometer cable to him so he could get the speedometer connection correct. The length of my original cable was perfect (about 4') so that is what he made the new cable length to. Received the new cable from ACI in about a week and installed it on the car. Went out on the highway and used the mile markers on the side of the road to check the odometer. Worked out that for every mile I traveled the odometer said I traveled about 1.35 miles. Gave this information to Tom at ACI and he worked up a right angle ratio adapter that slowed down the speedometer. I needed a right angle adapter due to the amount of space in the transmission tunnel. Received the right angle adapter in about a week. While I was taking the odometer readings I was also making speedometer observations using a GPS receiver. When the speedometer read 100 MPH the GPS receiver said I was doing 70MPH. Talked to Tom about this and he said he works off the more accurate gear driven odometer to get the ratio adapter right. After installing the ratio adapter on the car the odometer and speedometer are accurate.

Cost Detail

Description

Cost

Detail

4' Speedometer Cable

$36.05

with tax and shipping

Right Angle Ratio Adapter

$86.24

 with tax and shipping

Total

$122.29

 

 

 

 

 


Right Angle Ratio Adapter on Transmission


Gauges all working

 

 

Odometer

Mile Marker

Correction Factor

18.3

16

19.7

17

1.4

21.1

18

1.4

22.4

19

1.3

23.8

20

1.4

25.1

21

1.3

26.5

22

1.4

Odometer Reading - 8.2

Miles Driven - 6

1.3667

Total average correction over 6 miles

 

 

Other Speedometer Sources

D&D Fabrications - Dan Lagrew
8005 Tiffany
Almont, MI 48003
810-798-2491

Dan can convert the MG right angle speedometer drive so it will connect to the T5 transmission and your original cable. I was not able to use Dan's system because I have the wrong color gear in the transmission. Call Dan for details. It was the lowest cost system that I found.

 

 Speedometer Links

MGB Speedometer Types

MGB Speedometer Cross-Reference

 

 

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 This page Created By
Jim Miller
v8mgb@yahoo.com

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