Mechanical tachometer to electric

[jcsb]

Has anyone changed the mechanical tachometer to electric? Modified the old housing? I have a 60 BN7. Here is a picture of what it looks like.

John

 

[maxwedge5281]

i believe that healey rick changed ine over to electric. he is on here often and will most likely respond!

 

[HealeyRick]

John,

Are you trying to convert to electric and retain the white face gauge? You can't just substitute the white face onto a BJ8 tach as the gauge sweeps are different. There may be a way to change the electronics on the BJ8 tach to match the readings on the white gauge face, but I don't have the slightest clue how to do it. The other alternative would be to have a new gauge face made in white that would match the readings on the BJ8 tach. I wanted to keep the original tach when swapping in my V8 so I replaced the guts of the tach with SW innards and kept the original face. How I did it is here: https://forum.britishv8.org/read.php?13,8264 You could do something similar by using a tach calibrated to work with a six cylinder and having a 270 degree sweep that goes from 0-6000 rpm

 

[jcsb]

Thanks Rick for the info and yes I wanted to keep the same look. I am going to fuel injection from AHSpares and I could keep the mechanical tach but thought since I could pick the signal off the ecu it would be more efficient. If I do it I'll post to help anyone else that might want to do it. Thanks for your link I will review it.
John

 

[rjc157]

I would call Nisonger and see if they could do it

 

[HealeyRick]

John,

As you probably have seen, Steve Thomton went with fuel injection on his Rally replica BJ7. Since he went to a lot of effort to make it look like a period car, I thought he may have figured another way to convert to electronic tach. Looking at the video, though, he has replaced his tach with a black faced one (see near the end of the vid):

Some of the Sprite guys have been using Speedhut gauges, who will custom make just about any dial face and even use your own artwork. This one may work for you if they did a new face: https://www.speedhut.com/gauge/GL4-TACH-02/16/Tachometer-Gauge-8K-RPM Here's a link to one of the Sprite discussions: https://www.britishcarforum.com/bcf/showthread.php?94580-Speedhut-Gauges&highlight=speedhut

 

[jcsb]

Rick,
Just spent the last 45 minutes reading your thread in BritishV8. Appears we're about the same age since I saw B,S,& Tears when I was in school on the west coast. Very interesting read. Not sure what I'm going to do yet just exploring the options, but would like it to appear original.

John

 

[jcsb]

John,

As you probably have seen, Steve Thomton went with fuel injection on his Rally replica BJ7. Since he went to a lot of effort to make it look like a period car, I thought he may have figured another way to convert to electronic tach. Looking at the video, though, he has replaced his tach with a black faced one (see near the end of the vid):


Some of the Sprite guys have been using Speedhut gauges, who will custom make just about any dial face and even use your own artwork. This one may work for you if they did a new face: https://www.speedhut.com/gauge/GL4-TACH-02/16/Tachometer-Gauge-8K-RPM Here's a link to one of the Sprite discussions: https://www.britishcarforum.com/bcf/showthread.php?94580-Speedhut-Gauges&highlight=speedhut

I have some custom Speedhut gauges they made for a 308 Ferrari I'm rebuilding. Good people to deal with. Here is the set I had made.

John

 

[HealeyRick]

I have some custom Speedhut gauges they made for a 308 Ferrari I'm rebuilding. Good people to deal with. Here is the set I had made.
View attachment 32876
John

Nice cavallino rampante! Don't know if it matters to you, but if you try the Stewart Warner gauge transplant, the gauge does not park at "0" when the current to the gauge is cut off. It will keep a reading between 2-3k on the needle. Once you power the gauge, it will zero and provide proper RPMs when the engine starts.

 

[jcsb]

Nice cavallino rampante! Don't know if it matters to you, but if you try the Stewart Warner gauge transplant, the gauge does not park at "0" when the current to the gauge is cut off. It will keep a reading between 2-3k on the needle. Once you power the gauge, it will zero and provide proper RPMs when the engine starts.

Thanks Rick. You might not have noticed, but the numbers and emblem are dark blue which is the same color as the car. I sent them a jpeg of the horse and told them what color I wanted. Very accommodating people. Still working on that rebuild too. I hope to take the time to catalog the resto-mod since I'm doing a lot of mods.

John

 

[GregW]

Hi John,
Do you have the injector kit yet? It may tell you (or AH Spares could) what kind of signal the ECU puts out. When I installed a Jacobs ignition, my BJ8 electric tach wouldn't read the signal. I had to have the tach converted to read a square wave. North Hollywood Speedo did the work for me.

 

[jcsb]

Hi John,
Do you have the injector kit yet? It may tell you (or AH Spares could) what kind of signal the ECU puts out. When I installed a Jacobs ignition, my BJ8 electric tach wouldn't read the signal. I had to have the tach converted to read a square wave. North Hollywood Speedo did the work for me.

Hi Greg,
The ECU is an Omex. I'm going to have to do some investigating to determine what I can use. They say that it replicates the coil negative pulse. I'm building a engine run stand with a electronic tach so I will get a chance to see then.

John