VDO Boost Gauge Installation
Jeff Thornton
Introduction
These instructions were written to help people install a VDO boost gauge on a 1987 Turbo Regal; although many of the items are common to other cars and/or boost gauges. The credit for these instructions goes completely to Ken Mosher. Ken wrote the original version (bstgauge.txt) of these instructions and even helped me with a question that I had. I simply added a few suggestions (my two cents worth), to hopefully make it a little clearer for you, and drew the diagram for these instructions (bgauge.gif). Since this is the first item on any reputable list of items to improve your TR, I thought it should have a nice set of instructions. If you have any questions/ additions/comments, I can be reached at jeff@ra.me.wisc.edu. Good Luck!
Procedure
If your kit did not come with a plastic tee piece and three short pieces of vacuum hose you will have to drive to the auto parts store for these pieces :-( Bring the clear plastic tubing that came with the gauge with you so you can get the right size vacuum hose. Buy a 1/8th inch tee piece and a foot of vacuum hose that just fits OVER the clear plastic tubing. The clear plastic tubing is 1/8th inch outside diameter. When you are there, buy some of those handy little plastic ties (zip ties). You'll need at least 6 of them for the job, not including routing the tubing to your gauge) so buy a bunch of them. Buy the smallest size they have - it'll make the job easier.
  1. Locate the metal vacuum/pressure hose that goes from the top of the throttle body (with all the other lines) --> heater rail passenger side ---> back of the manifold ---> flexible coupler ---> fairly rigid little plastic tube (approx 1/8 inch outside diameter). The throttle body is located just in front of the plenum.
  2. For a 1987 TR, this boost line is connected to the fourth port of five (counting from the front of the car) out of the passenger side of the throttle body. Refer to the diagram in your engine compartment for details. The diagram is located near the far left corner of the engine bay as you face the car. The diagram refers to this line as "To Boost Gauge".
  3. Cut three two-inch sections out of the vacuum hose you bought and place them over the outlets in the tee piece. Use wire ties to make sure these sections do not come off under boost. I found that a needle nose pliers and a regular pliers work great for snugging the plastic ties. Refer to the drawing "bgauge.gif" located in the archives for a drawing of the "T" that you'll be putting in the boost line.
  4. Connect one end of the clear plastic tubing that came with your kit to the "leg" of the tee - this makes sure that the original line has a straight- through shot in the tee and does not have to make a 90 degree bend.
  5. Snip the somewhat flexible tube (not the coupler) of the boost line , making sure to not snip the tube as it makes its bend toward the firewall. Snipping too close to this bend might cause the rubber vacuum hose to kink at this spot. I connected mine about 6 inches past the bend towards the fire wall.
  6. Now use the straight thru part of the "T" to join the two halves of the snipped tube back together. Again, use vacuum hose and wire ties or small hose clamps to secure everything. You don't want leaks or things blowing off!
  7. Route the clear plastic tubing behind the coil pack and out of sight over to the driver's side of the firewall. Use the wire ties to secure the line and make sure it doesn't rest against anything that gets hot.
  8. Drop the bottom part of the dash (a couple/few screws around the pedals) - its the black plastic piece that keeps sagging and is really easy to get off.
  9. Now comes the really fun part - NOT! We have to get the clear plastic tubing into the drivers compartment. Some people say that its easier to push the tube into the drivers compartment, I've found that's its easier to pull it in.
  10. Use a piece of coat hanger (straightened) to poke thru the grommet in the firewall (it's kind of high, up by the steering column) from the drivers compartment to the engine compartment. This grommet has a few wires and the speedometer cable going thru it. You might have to loosen the securing strap a bit and poke around with the wire to get it thru.
  11. Go back to the engine compartment and find the wire that you just pushed through and carefully pull enough of it into the engine compartment to work on.
  12. Carefully slide the clear plastic tubing a few inches onto the straight coat hanger. Take some black electrical tape and tightly wrap the wire - starting a few inches below the tubing and working to a few inches above the tubing. Take your time and do this right or you'll be repeating this step! Make sure the transition from wire to "tube and wire" is relatively smooth.
  13. Go back to the drivers compartment and gently pull the coat hanger. It should pull the tubing thru and you can un tape the end when you get a hold of the tubing. Take up all the slack and secure things in the under hood region the way you want it.
  14. Route the hose to where you want the gauge - I used those handy plastic ties again to secure everything.
  15. Screw the brass fitting onto the back of the boost gauge (the smaller of the two which fits on the back of the boost gauge). The other one isn't needed (along with a few other brass fittings). Tighten, but not too tight.
  16. Put the brass nut over the clear plastic tube and then fit the little compression sleeve over the tube end.
  17. Screw the brass nut onto the fitting that now comes off the back of the boost gauge using two open end wrenches. Make sure that the tubing does not slide out (or back) while you are doing this. Get this fitting relatively tight so that the boost line will not leak or blow off.
Option 1
Run one of the terminals on the back of the gauge to a good ground screw.

Run the other terminal to the back of the radio (you'll have to pull the radio out to do this). You can splice it (with all other gauge lights) into the wire that goes to the terminal marked "LAMPS". This way your dimmer switch will dim the gauge lights right along with the instrument panel gauges.
Option 2
When I read that I would have to pull my radio out to do this (option 1) - I balked a little and found a somewhat easier way. I spliced my wires into the positive and negative wires that lead to the little light that tells you which gear you're in at night. Its the one located in front of the shifter in the console (between the bucket seats). You'll have to pull the ash tray out and the unscrew the screws located under the ashtray. Then remove the black plastic piece that funnels the light to the gear marking (R,N,D etc). You'll see the holder for the light - grab the light socket and turn gently - it will pop right out. (or in my case it was already out ) Trace these wires into the console and splice into them using some of those handy electrical splicers where you don't have to cut the wire.

Before reassembling everything, test to make sure everything is working and is in the right place. Then reassemble, put your tools away, and go for a ride - show off that nasty car!

If you accidentally put a kink in the rubber tubing (as I did) don't panic - its easy to do and easy to fix. Simply cut the tubing and splice a very short section (approx 1 inch) of vacuum hose over both sides of the tubing; making sure to secure the line with plastic ties as you did earlier. Whoever decided to package the tubing in those tight little spirals never had to use it in its wound form or they never would have done this!


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