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The below schematic should be used to wire the FAST remote IAC to the Holley main harness. Removal of the flat Holley connector will be required to splice in the supplied square connector. Use the below schematic for proper installation. 

Holley harness purple/yellow to connector terminal A 

Holley harness purple/blue to connector terminal B 

Holley harness purple/black to connector terminal C 

Holley harness purple/white to connector terminal D

The pin layout is provided in case it is needed. The barrels of the supplied connector points towards you with the connector tab on top and the wires out the rear for correct terminal orientation.

Holly Wiring Harness





What Is A MAP Sensor & What Does A MAP Sensor Do?

Remember science class when the teacher shouted “Pay attention! You might need this someday!” ? Well, as much as I don’t want to admit it, that teacher was right. Let’s touch upon the basics and see if it rings a bell?

The Basics:

  • First off – MAP is an acronym for Manifold Absolute Pressure. MAP sensors measure the air pressure in your intake manifold which helps the engine’s computer determine air / fuel ratios. MAP sensors are set to “zero” from the factory. So with the car off, and the key on, the MAP sensor will read “zero” at sea level.
  • On earth, we have 14.7 Pounds per Square Inch (PSI) on us at all times at sea level.
  • “Bar” is a measurement of pressure. 1 Bar = 1 atmospheric pressure, which is 14.7 PSI.
  • The absence of pressure is measured in “Inches Of Mercury” (in. hg). (Finally we get to use the periodic table of elements in real life!)
  • -1 Bar = -29.4 in. hg
  • 1 Bar = 29.4 in. hg
  • Naturally Aspirated = without a turbocharger or supercharger. Also known as “N/A”.
  • Forced Induction = with a turbo or supercharger
  • In forced induction applications “Boost” is automotive slang for PSI
  • Stoichiometric Air Fuel Ratio = The ratio of the exact amount of air it takes to burn a fuel completely.
  • Stoichiometric for Gasoline Engines = 14.7 : 1 (14.7 parts air to 1 part fuel).

What Does A Map Sensor Do

Now some of that good stuff:

With a N/A engine running, the MAP sensor may see readings anywhere from -29.4 in. hg to 0 PSI depending on how hard you smash the pedal. The more you hit the throttle, the closers to 0 psi the MAP sensor will read because there is less vacuum in the intake manifold. On an engine with forced induction, the MAP sensor will also measure boost (finally above zero!).

When MAP sensor data is combined with an air temperature sensor and a known engine speed, the ECU (engine’s computer) can accurately calculate the air flow rate of the engine, which then means it can calculate fuel. It does this with fuel maps that are programmed into the ECU. The fuel map guides the engine to its happy stoichiometric place. Easy enough right?

So what is so great about a 3 or 3.3 Bar MAP sensor? Why do people use them on cars that they don’t belong on?

Some cars that come stock with superchargers or turbochargers have 3 or 3.3 bar MAP sensors from the factory. So horsepower addicts like to take their own project car, stuff more boost into it than it was ever intended to have (More Powahhh!), and run a tunable computer system to handle the changes. Since a 1 Bar sensor can only read up to 14.7 psi (which is really zero here on earth), a 1 Bar sensor can’t handle any forced induction applications. EEEK! Any type of forced induction puts pressure (above zero) into the intake manifold, and therefore horsepower seekers need a MAP sensor that can accurately read those pressures. This is where the 3 or 3.3 Bar comes into play. A 3 Bar sensor can read up to 44.1 PSI (Subtract the 14.7psi of atmosphere, and it can actually can read up to 29.4 PSI.) So, if a person were to put a 1 Bar sensor where a 3 Bar goes, the ECU would freak out when the boost arrives, and wouldn’t know what to do with the air/fuel ratio because the numbers on the fuel maps don’t add up anymore. The moral is that the 3 and 3.3 bar sensors are perfect for this type of thing because of their simple 3 wire connector, reliability, and accuracy. Oh and the price is great too!

Goes in the blower manifold or intake manifold Blown or Unblown  

What Does A Map Sensor Do


TECH QUICKIE: Camshaft Lobe Separation Angle And Power Relationship

December 29, 2015

Selecting a camshaft for a given engine’s purpose usually involves a compromise between low- or high-end power options, and the lobe separation angle (LSA) is one of those factors where engine builders have to make a choice between those priorities.

“The lobe separation angle is the angle in camshaft degrees between the maximum lift points, or centerlines, of the intake and exhaust lobes,” says Eric Bolander of Erson Cams. “It affects the amount of valve overlap; that is the brief period of time when both the intake and exhaust valves are open.”

click here to read the entire article and see all the images


Is it possible to have a blower on 93 octane pump gas without the stripping in the rotors?

Why stripped or not? Does Compression ratio matter? 

If yes that I can get a blower without the stripping in the rotors, what is the max horsepower cutoff without the stripping and 93 octane pump gas?

This is one of the most misunderstood elements of blowers. Stripping is done in levels. So a stripped blower is always more efficient than a non stripped one.  The degree of tightness is what is to be considered.  All of our Blower shop Blowers are stripped for specific fuels. Gas  requires more clearance and thus looser stripping to eliminate heat. Alcohol and E-85  can accept much tighter stripping since alcohol is a cooling fuel, and the tighter the stripping the more boost a blower can make.

Gas is such a low octane (resistance to detonation)  that if a blower produces much boost, and when coupled with a high static compression, it will eclipse the ability of 93 octane to  not detonate, and that is how engines are destroyed. So we have a chart in our technical area which tells how much boost you can have with pump gas and be safe. Think of a blower as a compressor or like piston rings-  Tighter clearances = more ability to work.

Pump E-85 can be dangerous to try and figure out because it can be as low as 100 octane or as high as 105 at any given time.

Drum C-85 is always approx 117 octane usually good up to 18-1 compression.

Methanol doesn’t have a  boost limit for all practical purposes and will resist detonation to over 30-1  compression.

The “Effective” compression ratio has to be calculated by first knowing the engines compression (Static), then adding the blowers boost which gives an answer called  “Effective” which is what the engine is seeing as the compression ratio.

So 8-1 compression +  10 lbs of boost = about 14-1  compression (too much for pump 93 octane) call us for help on this before you hurt something.




Alkydigger’s Turbo/ ProCharger Boost referenced Flow Valve BV1062 Alkydigger’s Turbo/ ProCharger Boost referenced Flow Valve BV1062


Alkydigger’s Turbo/ ProCharger Boost referenced Flow Valve BV1062

This valve provides a way to limit the flow of fuel away from the engine during boost cycles.

The way it works is by normally being wide open with no boost.

When boost is sent to the valve, from any source where boost is available before the butterfly, to the -6 fitting on the valve it causes the valve to begin to close.

More boost which is regulated by the “Air Valve” will cause it to close more quickly – Less boost will make it close more slowly.

The Air Valve uses “Pills” to allow more or less boost to get to the Turbo valve. Larger pill = More Boos t= Quicker Closing = more fuel to the engine sooner.

The -12 Fitting gets returned to the tank. The -12 wants a fairly short hose or direct fit to the tank with no turns if possible.

The -8 Fitting receives the fuel from a direct source from the pump. Fuel pressure BEFORE it gets metered.

So in summary:

Smaller pill in the Air Valve makes it in effect leaner.

Larger pill in the Air Valve makes it richer.

Alkydigger’s Air Valve AV6001 is recommended, using 7009- Enderle pills. You should have pills in the .050 to .100 range on hand.

Alkydigger Fuel Injection





There are essentially 3 ways of by passing fuel for the main jet in most all mechanical injected engines  –  One of these 3 Valves will be mounted between the pump and the metering (Barrel) valve –

The Enderle is a simple 2 lb check valve with a 7003A pill holder and uses screw in Enderle pills

The Kinsler is a snap apart Quick Change valve which uses Hilborn Drop in pills

The Hilborn is the traditional Screw apart  Hilborn main by pass which uses drop in Hilborn pills, of  course.

Choose a valve below and then order either Hilborn Pills F565 or Enderle pills EN7009Main Jet By Pass Holder options

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