BellePlaine's New VDO Tach

[BellePlaine]

This is the result of my latest project, the installation of the VDO 7,000 rpm tach (#333 051) in my 1975 bus.



As you can see, I've modified the face to look at home. To do this, I had a new face made with a font closely matching the font from the speedo. The face was printed on vinyl and spray glued it onto the VDO tach face.



#333 051 comes with two 3 watt light bulbs which I thought would be too bright and out of place compared to the VW's original 1.2 w #2721 bulbs. So I carefully cut out some bulb ballasts from my parts bus instrument cluster and JB Welded them to the tach's light holes. But before I did that, I stuck a bit of green cellophane into the light holes to match the original green gel like that of my stock speedo.



Using the original bulbs and ballasts meant that I needed to get creative with the grounds for those bulbs. I had to use brass model railroad track connectors which were small enough to connect to the ground from the bulb and allow a small spade connector to attach.



I've read about other VDO tach installations having problems with "bouncing needle" and learned that the solution was to use a Radio Shack (IN4005) Rectifier Diode at the coil. I added spade connectors to mine.









As soon as I'm able to figure out why YouTube is not allowing me to upload a short video I took of the tach in action, I'll post it. In the mean time, I'm enjoying my new tach. It has always perplexed me on why VW didn't give us a proper tach in the first place.

[whc03grady]

You even flipped over the 6 and 7, corresponding to the 80 and 90 on the speedo--nice attention to detail. Where/how did you get the face printed anyway?

[Mike Boell]

Very nicely done with attention to detail.
Mike

[BellePlaine]

You even flipped over the 6 and 7, corresponding to the 80 and 90 on the speedo--nice attention to detail. Where/how did you get the face printed anyway?

Thanks! I work a graphic designer, who lives in California and I in Minnesota. We emailed back and forth until we settled on a face that was pretty good. I didn't know if I should make the numbers single digit or double digit. I was trying to guess what would have VW have done but in the end I figured that I doesn't matter too much anyway. I went to OfficeMax to have the file printed on vinyl. The face is exactly 7 cm in diameter which was a little silly because the smallest piece of vinyl that OM can print was something like 2' x 1'. But I chose vinyl because it doesn't throw a glare like gloss or even matte paper print.

[Amskeptic]

You even flipped over the 6 and 7, corresponding to the 80 and 90 on the speedo--nice attention to detail. Where/how did you get the face printed anyway?

Thanks! I work a graphic designer, who lives in California and I in Minnesota. We emailed back and forth until we settled on a face that was pretty good. I didn't know if I should make the numbers single digit or double digit. I was trying to guess what would have VW have done but in the end I figured that I doesn't matter too much anyway. I went to OfficeMax to have the file printed on vinyl. The face is exactly 7 cm in diameter which was a little silly because the smallest piece of vinyl that OM can print was something like 2' x 1'. But I chose vinyl because it doesn't throw a glare like gloss or even matte paper print.

That is a fine job. Beer and tach on tap.
Colin

[sped372]

Nice work!

It has always perplexed me on why VW didn't give us a proper tach in the first place.

I'm sure it was all about $$$. Once you learn the shift points it isn't really necessary since the vehicle speed is directly proportional. When did they stop putting the marks in the speedo housing for the shift points? I always thought that was a clever poor-man's tach substitute.

[BellePlaine]

Here's a short video of the tach in action.

http://www.youtube.com/watch?feature=pl ... E0NfYNZXxU

Now that I'm using this tach, it kind of surprised me at how high of rpms the engine turns at highway speeds. I'm running a 1.8L, fuel injected engine along with a 3-rib transmission and I'm about at 3,800 at 70 mph. I wonder if those high rpms are needed to keep the engine cool.

I'm sure it was all about $$$.

You're probably right, sped372. These were, after all, economical cars I guess. I just think that its interesting that VW gave these cars a blank gauge for 11 years for the purpose of an option for a clock instead of a useful tach.

[Amskeptic]

Now that I'm using this tach, it kind of surprised me at how high of rpms the engine turns at highway speeds. I'm running a 1.8L, fuel injected engine along with a 3-rib transmission and I'm about at 3,800 at 70 mph.

Worse yet, your speedometer is off.

002 transaxle to July 73 . . . . 70 mph = 4,060 rpm

002 5-rib to August 75 . . . . . 70 mph = 3,680 rpm

091 to end . . . 70 mph = 3,750 (note that the 5-rib is slightly taller)

[vistacruzer]

Nice work looks great!