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Chevy Nova EFI Kit - Lean, Mean, And Green
Edelbrock's Pro-Flo XT EFI Kit Gives A Nova A Kick In The Rear, Better Manners, And A Smaller Carbon Footprint.
Mar 1, 2009
Airaid Filter Company
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Chevy Nova EFI Kit - Lean, Mean, And Green
The donor '70 Nova is an awesome shade of metallic mint green.
We threw it on the dyno at Tune Time Performance in Toms River, New Jersey, for some preliminary emissions and dyno testing.
Our base numbers were 174 corrected rwhp and 228 lb-ft of torque--surprisingly good, we think.
Trick of the Trade: With the '68-72 Nova, you can prop up the hood to vertical by taking out the front hood bolt on each side, loosening the back and pushing it back. This makes life so much easier when working under the hood. The only other option is taking the hood completely off when installing a kit such as this.
Next came the intake manifold. After disconnecting all the wires, throttle linkage, radiator hose, and distributor, the eight intake bolts can be removed. Most manifolds require some persuasion as the silicon creates a tight bond. A quick wedge with a flat-head screwdriver and out she comes.
The intake surface must be cleaned and prepared to ensure a good seal with the new intake manifold. At this point, we let the 5-point-slow loser of the bunch jump in and do the dirty work.
After a bead of silicone across the front and back of the block where it meets the manifold, and a set of Fel-Pro intake gaskets from the local parts store, the intake was set in place. Make sure all the bolt holes line up and begin installing them. We replaced the original rusted intake manifold bolts with new ones to ensure the "new" look.
Next, we dropped in the new Mallory electronic distributor, as this would be difficult to do after the wires are hooked up and in the way. We also wanted to make sure that we had enough clearance between the firewall and the rear of the intake. It fit like a glove.
Now is the perfect time to organize all the wires. Using the very helpful directions that come with the kit (also available at www.edelbrock.com), we maneuvered the wires into their approximate location upon completion.
This also helped when we attached the new coil to the firewall using sheetmetal screws. You don't want tension in the electrical lines, but also don't want to be wading through wires.
Trick of the Trade #2: While installing the new thermostat, we drilled a hole through the base ensuring that air does not get trapped in the manifold, leading to a problem with circulation. The hole ensures that the manifold is filled with water at all times. We cleaned and painted the thermostat housing off the original manifold and reused it.
Next, we mated the engine bay wiring harness with the cockpit wiring harness. The instructions ask that you drill a 1 1/2-inch hole in the firewall to do so. We tapped into a previously made hole that was once used for an air conditioning system.
We then made and ran the fuel line and return. The kit comes with 20-feet of flexible fuel hose as well as all the ends and instructions on how to attach them. You can either create a new return line to the tank or reuse the original fuel supply line as the return. We decided to make a new line and ultimately had to order ten more feet of line to finish the job.
The O2 sensor needs to read the oxygen content in the exhaust system and thus must be mounted on the exhaust pipe. The hole was drilled, and the bung was welding into place.
Photographers note: Use a long lens and stand a few hundred feet away. Sparks do sting.
We had to drop the tank and install the new fuel hose. We simply attached a 6-inch piece of hose to a fitting and bolted it to the mount. No filter was needed as we will add an inline fuel filter after the fuel pump.
We mounted the fuel pump and fuel filter to the inner framerail, clear from danger of the tire, shock, and leaf spring.
The in, return, and wiring for the fuel pump was all run together down the length of the car and pull-tied together every six inches. This ensures that they don't move and scrape on anything. Any contact could cause a catastrophe. We made sure we had plenty of clearance between the lines and e-brake wire.
In the interior of the car, we used double-stick tape supplied with the kit to mount the ECU. Also, we attached the wiring components to it and made sure to sneak them up behind the dash and out of sight. Then, a wire was run from the wiring harness to a switched 12-volt source to give the ECU power, but only when the key was turned on.
Check out Matt Haufffe of Tune Time Performance using the XT Calibration Module that comes with the kit. The base program must be installed as per application with the tuning CD provided with the kit. Here, Matt was tuning the fuel map on the dyno for optimal performance. The XT provides an assortment of tuning tools, including fuel and spark maps, digital diagnostic readouts, and idle adjustments, among others.
The finished product. The instructions made installation very easy. All the wires have unique ends on them, which eliminates the chance of hooking them up wrong. Ford-boy gave us an elbow to use and we picked up a cone-style filter from AirAid to button it up.
After all was said and done, we hit Tune Time Performance again to get some final numbers.
We made 210 hp and 267 lb-ft of torque, an increase of 36 hp and 39 lb-ft, thus matching our goals. We increased fuel economy from 13.8 to 18.9 mpg, an increase of 5.1, and a savings of over $700 a year based on how the car is currently used. Hydrocarbon content dropped from 160 to 118, making the 307 far more emissions friendly. Throttle response is now instantaneous.
Last, but certainly not least, a few cranks of the starter and you are ready to rock. No stumbles, stalls, or other problems.
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