GNX-Style Dashes - The X Styles

In the force-inducted EFI world, proper gauges are a must. Your ride has too much happening with boost, fuel, oil and electricity to rely on inaccurate, factory-style idiot lights. Speaking of your ride, you Turbo Buick guys out there will agree with me when I say that whoever signed off on the horrible LEDs for engine RPM and boost pressure must have seen Tron too many times--God-awful. Throw in that 85-mile-per-hour speedo, and we've got a dash that only a grandma could love. So it's all in favor of better gauges, then?

Along a similar line of reasoning, if you're going to upgrade to new gauges anyway, you should really consider investing in the proper tools needed to accurately and safely tune your ride. A scan tool, while invaluable in keeping your engine together, can only do so much for precise tuning. That's why an exhaust gas temperature gauge and a wide-band oxygen sensor gauge should be standard-issue. Pricey, yes. Absolutely necessary? That depends--how many tuning-related engine repair bills have you paid lately?

GMHTP's in-house Turbo-T is equipped with a factory, analog-style dash, as well as four small gauges that were manufactured sometime after the Paleozoic era. I grudgingly admit that they kept me as informed as they could for the last 11 years. But for the ultimate in style, toss those A-pillar and console pods and look at the dashes offered by Performance Instruments.

Some Internet gauge research brought me across PI's website (www.gnxdash.com), and two things struck me about the dashes: the seemingly effortless fit into the stock dash location, and the limitless amount of options available to the buyer. Each conversation with Performance Instruments' Tom Houser got me more into the idea of dash customization, and Tom was happy to suggest the kinds of options that would work well in my specific application. Although Sacramento-based Performance Instruments has several dash layouts to choose from, I like the X-Treme--with holes for eight 2 1/16-inch gauges, you might run out of parameters to measure before you run out of room. And frankly, the big 3 3/8-inch speedo hole looks money right in the middle of everything.

When it came time to fill those holes, I contacted Auto Meter for a full serving of its Phantom electric gauges. In the 3 3/8-inch size, I requested the 160-mph speedo (part No. 5888, $285). And in the 2 1/16-inch sizes, I went with the 5766 dual-channel EGT ($333), the 5777 30-pound boost/vacuum ($247), the 5763 electric fuel pressure ($300), the 5727 oil pressure ($82), the 5737 water temp ($62), the 5714 fuel level ($54), and the 2698 tachometer ($137). This Z-Series tach obviously isn't a 2 1/16-inch Phantom, so Performance Instruments offers a service to convert it to a Phantom look to blend in with the others.

And finally, anyone who loves the idea of a quality wide-band oxygen sensor and 2 1/16-inch gauge combo should look no further than Powertrain Electronics. It sells the G100 Air Fuel Ratio system, an all-inclusive wide-band setup manufactured by ECM (Engine Control and Monitoring) in Los Altos, California.

Need references? General Motors has utilized ECM for the last 10 years to provide air/fuel ratio instrumentation for new car and truck calibration. When I heard that, I knew that my overboosted little LC2 would be in good hands. Powertrain Electronics sent out the G100-RAC ($995 list, $895 if you mention this article!). It ain't cheap, but quality never is.

All gauges were sent to Performance Instruments where they were installed and wired up. Soon afterwards the 9-gauge Racer X-Treme was shipped to my door, and not long after that, I was at Ron's Custom Auto in Kenilworth, New Jersey for the install. So how did it turn out? Read on.

Wide-band O2 technology is finally filtering down to the enthusiast market, but you don't see any of those $400 wide-bands being used by the OEMs for product calibration. Powertrain Electronics markets the G100 Air Fuel Ratio system, and your boosted EFI GM can't afford to be without it. Shown is the white-faced G100-RAC gauge.	The G100-RAC comes with the capability to measure a motor's true air/fuel ratio to plus or minus two percent accuracy--anywhere, anytime. Throw in easy field calibration, 1-minute recording and playback, 5-volt analog output to a scan tool, trouble code retrieval, and the ability to plot a curve on a DynoJet dyno with an available module, and you may be looking at the most affordable wide-band O2 system in existence.	Auto Meter's Dual-Channel EGT kit includes two sets of probes, along with all necessary wiring, heat sleeves, and a control box. The box will record and store peak exhaust gas temps, has an adjustable alarm to warn the user of an impending meltdown, and allows the user to select which channel to monitor. I'll only be using one channel for this project.
My man Paul Joseph down at Ron's Custom Auto knows his way around a wiring harness, so I tapped him and his crew to do the installation down in Kenilworth, New Jersey. Thanks to Performance Instruments the dash and most gauges are an easy install, but the Auto Meter Dual-Channel EGT and the ECM wide-band unit would need a little customization and modification work to our exhaust and interior wiring.	The swap got rolling when Ron's Custom Auto tech Eloy Perez disconnected the T's battery. The four-gauge pod that came with the Buick retains coolant temp, oil pressure, voltage, and boost gauges. Since this install was done before I owned the car, Paul Joseph was cautious not to remove any wires from the rat's nest that we may still need. With the gauges' wires cut, he removed the pod.	Under the factory dash, Paul pulled the plastic trim panels by removing the 7mm screws, then removed the two 15mm steering housing bracket bolts to drop down the steering column and give himself a little more room to work.
The factory trim panel covering the dash is unclipped and removed, then six 7mm bolts come out to remove the dash hood (trim pad). Paul places it aside.	Three 7mm bolts on the left side for the headlights/dimmer/twilight sentinel switch are removed, and on the right side there is a two-bolt 7mm switch (for rear defog, if applicable). The switch assemblies are pulled. The white (let's face it folks, by now they're yellow) factory wire harnesses that connect the headlight switch are unclipped and pushed back into the housing. There are seven 7mm bolts that hold the housing in, which are all removed.	The upper speedo cable is undone under the hood, then the speedo cable behind the now-loose cluster is popped off--this is easier if the dash pad covering the front speakers is off, but it will come with patience.
The stock VSS sensor, the main 18-pin connector, the 8-pin connector for the tach, and the Check Engine wiring and light bulb are all disconnected from the factory dash.	The stock analog dash is finally lifted out. Shown is the background wiring, the HVAC tube, and the dash support housing. The housing is sent back to Performance Instruments as a core for future customers, so don't mangle it.	Meanwhile under the car, Eloy yanks the four 15mm bolts from the crossover, then removes the pipe. The downpipe is unbolted and removed, and the passenger-side exhaust manifold is removed.
We will be retaining the factory O2 bung, as well as adding a wide-band O2 bung and an EGT probe, in the manifold close to the turbo. Ron's Custom Auto welded in the wide-band O2 bung and drilled for the EGT probe in a different manifold to save time. Now, the manifolds are simply switched. Always watch for clearance issues before drilling, as space is very tight in this area.	The stock O2, the ECM wide-band O2, and the EGT probe are all test-installed to check for clearance issues. They all cleared and after the manifold went back on, they were all tightened down.	The oil pressure sensor, located near the passenger-side frame by the lower radiator hose, was loosened with a 9/16-inch wrench, then removed. Our new gauge uses a new sender, which is installed.
The broken coolant temp sender, located on the front of the intake manifold, was removed with an 11/16-inch socket; a new one went in its place.	Auto Meter's electric fuel pressure gauge doesn't require a box; rather only this sender with a snap fitting--very nice.	The MAP sensor for my Auto Meter boost gauge was installed beside the original on the passenger-side fender, and it is brought into the vacuum system with a plastic T. I'll cover the MAP to prevent condensation from contaminating the sensor.
New dash time: installer Paul Joseph, who has done his fair share of GNX dashes, commented on the look and marveled at the simplicity of the Performance Instruments GNX dash. "Really nice," he expressed. "The great thing about this dash is that you don't have to take it completely apart or cut or modify the cluster in any way."	After the new VSS is installed, the boost tubing/EGT/O2 wiring is passed through the firewall, and a towel is placed onto the steering column, the dash is ready for a test-fit. Paul starts connecting the gauges and idiot lamps, connects the main harness connector, then wraps the excess wire in tape. All gauges, including the idiots, turn signals, high beams, etc. are checked for correct operation.	Finally, the Racer X-Treme is bolted up in the factory location. Reassembly is performed opposite of the way it was taken apart.
Time to run the wiring for the Powertrain Electronics wide-band and the Auto Meter EGT controller. The wide-band's control module was mounted underneath the radio pod with double-sided tape to provide access for calibration and adjustments. Connections were made to the ignition key, to the battery, the gauge, the record/playback pod, and the sensor itself. The analog output and brake-record-trigger connections won't be used now, but can be hooked up at any time.	The EGT controller, along with the wide band's record/playback control pod, were mounted inside the center console. A small hole was cut into the bottom of the console to run the wires through. I'll push SET/STOP and PLAYBACK simultaneously before a run to record the air/fuel ratios, and afterwards I'll also be able to check the max EGT readings here.	Next, the wide-band O2 was calibrated. With Eloy holding the connected O2 sensor, Paul turned on the ignition.
As the sensor heated up, the gauge started at 16, then began to swing clockwise over to 9, then went all the way around to 16.	After a three-minute wait, the included calibration screwdriver was put into the CAL POT hole of the control module. It was turned counterclockwise until the CAL LED light went out, then clockwise until that light just turned on again. After those steps the wide-band O2 was calibrated, and after it cooled down it was installed.	With all senders and sensors installed and all connections made, Eloy and Paul took the time to wrap every new component in black wire loom and route it to the perimeter of the engine bay. One look at the finished product, and it's very difficult to even tell that there was work done.
Here is the fully installed Performance Instruments dash. Notice that I have left off the included lens--I will be using the Peak and Warn buttons on the Auto Meter boost gauge. Visibility is excellent during the day or at night with the red lighting that I requested, and this instantly accessible data is exactly what I had in mind.