HEI Distributors - Fact Or Fiction
It wasn't all that long ago that GM engineers designed the original HEI system to tumkur gay dating the decades old points-type ignitions. In the mid-'70s, leaner mixtures demanded greater voltage and more spark energy to kick off combustion. The HEI distributor is still an inductive-discharge ignition, but exchanges points for an electronic device called a module. Since this system produces more voltage and amperage output than a point-type ignition, it requires a larger-diameter cap to prevent voltage crossfire inside the distributor cap.
The large cap also offers extra space to host the coil, making the HEI distributor self-contained. All you have to do is to apply a volt hot lead to the distributor and you're ready for the road. Early HEIs were infamous for giving up at speeds above 5, rpm-so many avoided them. This was true of the early-model distributors, but it didn't take GM long to modify the modules and coils to offer greatly increased hei distributor hook up energy at higher engine speeds.
These days there's a plethora of aftermarket high-performance modules, coils, and complete ready-to-run HEI distributors that can be added to a high-performance engine that'll provide excellent spark energy and rpm potential well in excess of 7, rpm. During the early years of HEI use there morphed a bunch of, well, we'll call 'em myths in regards to these systems-some possibly true, some blatantly false, and hei distributor hook up open to interpretation.
The following are the 10 ang dating daan 1000 questions common, along with some views, which are believed to dispel them. Take a look and see what you think. Inductive ignitions, like HEI - High Energy Ignitions, aren't as good for high performance engines and racing motors as CD-capacitive discharge ignitions.
This myth is only true when compared to stock HEI systems. Today, we are making high-output modules and coils that saturate fast enough to fire constant at high rpm. This firing ability also allows wider spark plug gaps-in the vicinity of 0. The benefit of wider plug gaps is a more complete burning of the fuel mixture. This is probably the oldest HEI myth of all. Actually, an HEI draws only 2- to 3-amps, compared to the approximate 6-amps an external oil-filled coil draws.
The hei distributor hook up amperage draw results in a much cooler running HEI coil. HEI Coils also run cooler because they are encapsulated in hei distributor hook up epoxy, which dissipates heat more efficiently than oil-filled coils. The solid epoxy, in comparison to oil-filled coils also eliminates the possibility of leaks. You can also lose some spark intensity when you run a coil wire to an external oil-filled coil as the voltage has to travel a longer path, creating more resistance.
For the most part there is only minor benefit to a billet distributor housing over a cast housing, at least in terms of better performance. Most castings are stable and straight hei distributor hook up modern machining techniques aid in narrowing the benefit gap in this respect. But, in the looks department, you've got to admit that billet looks better. The advance curve on a stock HEI is for the most part not fully advanced until 4, rpm, which is very slow.
In addition, low hei distributor hook up midrange performance motors as well as stock motors benefit from a more intense spark from idle, all the way up the entire rpm range as the fuel is burned more completely. Vacuum advance doesn't lead to more horsepower. Vacuum advance immediately begins to decrease as soon as you accelerate, and at wide-open throttle vacuum disappears.
However, it is recommended that you connect your vacuum advance hose to direct manifold vacuum because it will provide you with more vacuum advance at idle, which will help to keep your plugs cleaner. As long as you are at TDC on the compression stroke, it does not matter which terminal you use as your number one.
Because this is a high-compression high-horsepower motor, use solid core plug wires. Actually most HEI systems run well with spiral-core wires. The spiral core prevents internal wire vibration and prevents electronic interference. Actually no it doesn't, in fact, the silicone transfers the heat produced by the module to the distributor housing. In effect, causing the HEI housing to act as a heat sinc.
On an HEI, if you use the holes in the housing that were originally there for the vacuum advance, to install your vacuum advance eliminator, there is no cause for rotor phasing. It will hei distributor hook up be phased correctly due to the original design. Not necessarily a myth but a fact. A defective tachometer, can cause an HEI to malfunction. Redeeming the Gen II LT1 V-8 engine with some smart, modern upgrades. Keith Dorton and Automotive Specialists upgrade a daily driver Gen II LT1 with 21st century tech.
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Sign Up today for our FREE Newsletter and get the latest articles and news delivered right to your inbox. HEI Distributors - Fact Or Fiction 10 Common HEI Myths Jim Rizzo Jun 25, Share. MORE PHOTOS VIEW FULL GALLERY. Get Latest News and Articles. EZ-EFI Issues on Corvette Traced to Bad Valve Seals. Installing stainless steel exhaust on a C1 Corvette. LS SOS coils, ratcheting wheel dollies, and more new products for your Chevelle!
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