vdo tachometer swap

[65sprite]

I have given up on my smiths tach in my 65 sprite. I had it rebuild about a year ago by north Hollywood speedo and it worked fine till I added a petronox ignition. I have tried most of the usual suggestions regarding grounding, but it still either cuts out completely, or shows a rev count much higher than the tach on my - dwell meter.

I read Doug L's excellent article on updating to an rvc, but it still involves using old parts. I have found a listing for a vdo #333 160 which is a 4" diameter. looks like it would fit, but I can not get any other dimensions. I hate to blind order one. Has anyone tried this tach - have any info on its suitability? Thanks, ron.

 

[kcbugeye1275]

I substituted the smaller tac and speedo into my bugeye. The tac took modifiying the back of the can, but everything else was really easy. I do have the same ignition. The trick to make it look good is to take a small round item and set it on the glass and paint first black and then silver(to help reflect light) around the perimeter of the glass to hide the smaller guage. Both my guages have no bounce as they did before.

 

[bugimike]

I substituted the smaller tac and speedo into my bugeye. The tac took modifiying the back of the can, but everything else was really easy. I do have the same ignition. The trick to make it look good is to take a small round item and set it on the glass and paint first black and then silver(to help reflect light) around the perimeter of the glass to hide the smaller guage. Both my guages have no bounce as they did before.

Just a question, but couldn't you just adapt the guts from the smaller tach into a BE can to keep it looking right?

 

[65sprite]

I substituted the smaller tac and speedo into my bugeye. The tac took modifiying the back of the can, but everything else was really easy. I do have the same ignition. The trick to make it look good is to take a small round item and set it on the glass and paint first black and then silver(to help reflect light) around the perimeter of the glass to hide the smaller guage. Both my guages have no bounce as they did before.

Just a question, but couldn't you just adapt the guts from the smaller tach into a BE can to keep it looking right?

I can use the internals from another tach as I have a spare with a bad circuit board, but the face and trim is in good shape. Any SPECIFIC recommendations on a manufacturer and model of a new tach to use for the internal parts? I like the look and quality of the VDO, just not shure it will fit.
Thanks, ron.

 

[racingenglishcars]

I just used a Spitfire tach. I guess it isn't really adapting, it went right in using the BE faceplate.

 

[dklawson]

You can swap the VDO electronics into the Smiths can but it can be a lot of work. Visit Theo Smit's web site. Look at what he can offer to fit your budget, your desire for originality, and how much work you personally want to take on. There's nothing wrong with using modern electronics to power the old Smiths movement.

Theo developed a board that will replace the Smiths circuit in either an RVI or RVC tach. Theo retains the original movement. He was selling these boards as kits, or will do the upgrade and calibration for you. You'll need to email him for his current prices for this. The web pages below haven't been updated in quite a while.
https://members.shaw.ca/tsmit/tachmod/tachmod0.html

If you pursue the VDO option, be sure to shop for the best price. I've always had good luck and found good pricing with the folks at egauges.com I think you'll find the price of the new VDO to be in line with Theo's price for a pre-assembled tachometer upgrade board.

 

[65sprite]

Doug, thanks for the link. Probably the ticket if originality is important. I really want to either find a direct replacement in terms of size, like I suspect the VDO Vision would be, or fit new electronics into my spare (unusable) smiths can. The one I am currently using was recently serviced, and worked fine prior to the ignition mod. If I ever sell the Sprite (unlikely) and they want originality, I'll pull the Petronix and install the Smiths. I think egauges was one of the sites that came up on goolge. Looks like $85 - $95 for the VDO. Less than trying to mod the good one I have.

Thanks to all for your input so far.
Ron.