Prerequisite Tasks: N/A Additional Costs: $434 Time Requirement: 8 hours Date Started: May 10, 2013 Date Completed: May 18, 2013
The instrument cluster has been something that has bugged me about the car from the beginning. I wrote a post in January 2012, discussing this issue. Basically, the GTM is a WOW car. The lines, the performance, the handling all combine to create something special. Then you get in the car, look at the gauges and go, "Huh?" One of the major complaints about the C5 and C6 Corvette generations is that the interior does not match the exterior. One of the knocks on the GTM is that some people don't bother to finish the car. GTM 402 will be finished, and part of that, includes the WOW factor.
This is a task best done on a bench. This multi angle Stanley vice is fantastic for this job. I have one at both the Southern and Northern Man Caves. In this photo it is holding the Factory Five carbon fiber backboard used to mount gauges. I taped it to protect the surface. I have also used this vice to help crimp connectors, and I can mount almost anywhere on the car or the lift.
In the January 2012 post, I looked at Intellitronix, Speed Hut and Dakota Digital. I also considered the all in one dash consoles with data recorders, but these were running over a $1000 and I just didn't like the look. This entire task is about the look. Around January 2013, I decided to take another look at the the instrumentation puzzle. I came across Intellitronix's Create-A-Dash kit. At first I rejected the idea, then I came to realize this was exactly what I was looking for. Then I saw it on Stacey David's Gearz program (for a car builder this is a good show for ideas).
I planned to work on the instrumentation gauges on my current hiatus at the Southern Man Cave. I drop shipped the Create-A-Dash kit via Amazon and packed the tools I needed for the task. The gauges are available in white, green, blue or red. I watched a fair number of videos. I didn't want white (it just seems blah to me). I thought I was going to order blue, but it turns out red worked for my eye sight better.
The kit includes everything pictured here: Speedo, tach, volts, water, oil and fuel, smoked Plexiglas cover, backboard mounting hardware and sending units.
Each gauge requires eight spacers. You place the short ones against the base board and the longer ones between the gauge and the Plexiglas cover. There are a bunch of little bolts, nuts and plastic spacers for mounting. I poured them into a magnetic parts bowl. It is very easy to lose one of these small parts. Intellitronix recognizes that most of us drop things into to distant corners and includes extras!
To protect the backboard I cover it in blue painter's tape. The locations of each gauge is marked on the tape.
I super glued the spacers to the printed circuit boards. I know from experience that I don't do well with little parts, and anything I can do to make them easier to handle is worth the extra time.
I used the packing Styrofoam panels to support the gauges as I glued the spacers to the printed circuit boards.
My first idea was to drill a hole behind each gauge, install a grommet and run the wires to the rear of the panel. This doesn't work. The wires are too stiff to be bent so they can fit through a hole hidden by the gauge. I ended up drilling a hole for individual wires and cutting a slot for groups of wires.Once the smoked cover is mounted, these details are obscured.
The back side of the fuel gauge. The four wires coming off the end can not easily be bent to go through a hole, so I just let them go straight to the back board, where there is more room and slack on the other side.
I did a fair number of measurements to make sure I had things lining up properly. The bigger gauges measure 3.25 x 3.25 inches. They are smaller than the round five inch gauges and they use space more efficiently. The smaller gauges are 1.625 x 1.625 inches versus a two inch round gauge. This allows me to easily deploy six gauges on the back board with space to spare.
Gauge set set in place on the back board. You can see the lines I drew to help me get things set up. I worked off a center line. The center line is approximate, because the Factory Five back board is already cut and it seemed like the curve is slightly different from side to side.
There is some wiggle room for mistakes, but I tried to keep those to a minimum. Prior to drilling and holes and cranking bolts, you can get a good idea how things line up. The wires are stiff enough to support the gauges. I used a 5/64 bit to drill through the holes on the printed circuit board and into the back board. then I widen the holes on the back board with a 7/64 bit. I rifled through my Allen wrenches until I found one that fit into the head of the supplied bolts. The 1/4 inch nuts on the back side are easily handled with a ratchet.
Gauge set bolted in place.
The multi angle vice really came in handy. I could turn, spin and position the back board all different ways. There is no specific torque spec here, so just use common sense.
I couldn't resist. I hooked everything up to my 12v test battery. Note: If you get confused on the little gauges, just hook it up to a 12v source and they will tell you what they are.
The next part involves cutting the smoked Plexiglas cover. The kit provides a generous piece. You could almost get 2 covers out of a single piece. I positioned the Plexiglas sheet behind the factory Five back board, and held it in place with duct tape. I traced the curve. I discovered things here are not perfect either. I used a jig saw to cut the piece, then steel wool to smooth out the edge.
Cut Plexiglas piece.
I decided to use three bolts to attach the cover to the back board. I made a quick trip to Home Depot and picked up bolts, nuts and spacers. I trimmed the spacer to 5/8 inch. This way did not put any pressure on the gauges or the bolts holding them in place. I installed the connecting bolts on each side and on the center line between the speedo and tach gauges.
Hardware to connect the screen cover to the back board.
There remains the problem of the little toggle switches on the tach and speedo gauges. I hit on the idea of looking at the switches sideways. I used a straight edge to run two lines and plot the intersection point. Then I drilled a large enough (5/16 inch) so the switches could go up, down, left, right.
The circle is where the toggle switches come in contact with the cover. I was able to eyeball the location of the toggles with the aide of a straight edge. Once I had an intersecting point, I just had to drill a hole.
The final step is to install the high beam and signal indicators from the Factory Five kit. I decided these needed to be mounted on the surface of the cover, because they are not as bright as the Intellitronix gauges. I wrapped the wires in electrical tape (I should have brought some black from the Northern man cave) and ran the wires from the cover through the back board. I super glued the indicators for extra security.
The wires are wrapped in green electrical tape. The signal indicator is surface mounted on the cover.
Next steps involve adding a wire block to the back of the back board to handle all the wires and fabricating a gasket to run along the edge of the between the cover and the back board.
Not the greatest photo, but you can see the high beam and right signal indicators.
Here's my dilemma: I am in the process of building this incredible car. The GTM has an exotic body shape, a power/weight ratio that is otherworldly and a performance envelope that competes nicely with top end Ferraris and Porsches. I must admit - this is not an easy topic, because I haven't found anything that fits my idealized image.
My basic requirements for the gauge set are as follows:
Speedometer (200 mph minimum)
Tachometer (with red line indication)
Voltmeter
Oil Pressure
Water Temperature
Fuel
The stock gauges supplied with the kit are made by Autometer. These are fine guages that have a utilitarian look, not a supercar look. SO I embarked oin a search for something that reflects the GTM's supercar nature.
Stock gauge cluster supplied with the basic kit.
The first thing I discovered is most speedometers cap out at 120 or 160 mph. The GTM tops out somewhere north of 200 mph. This eliminates approximately 80% of the gauge sets currently available.
TPMS panel. I plan to mount this flush on the lower left side of the steering wheel.
The next problem is available space on the instrument panel. In addition to the guages, there needs to be room for turn signals, high beam and the radar detector screen. At the lower left of the instrument panel, I plan to install the TPMS (Tire Pressure Monitoring System) display. With the exception of signals, cruise control, stereo system and the Escort 9500ci controls, all other controls will located on the inTouchMax controller on the center console north of the gear shift.
Escort 9500ci display. This will be on the central dash panel.
Intellitronix makes a very nice digital gauge set. They will work with you on customization and they satisfy the basic requirements. They provide an analog/digital combination.
Intellitronix gauge set.
Dakota Digital has a number offerings. Their new product is an Oval Speedometer/Tachometer Information Center. This has everything except the water temperature. However, it incorporates turn signals, idiot lights, odometer, analog tachometer and software to record 1/4 miles and 0-60 performance. They offer a universal instrument cluster (it is as ugly as sin).
Speed Hut has a number of gauge sets. They have an online customization program that is quite flexible. In addition, they will further customize anything you want. One of the attractive things is their quad gauge. Instead of 4 holes drilled into to the dash panel, it combines the volts/oil/water/fuel into a single gauge.
Quad Gauge combines four gauges into a single unit.
Do I know what I'm going to put in the car? Not yet. Several times I have thought I had reached a decision, only to pause and search some more. I don't have to make a decision until later this year.
