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 88SSP (Special Service Package) Mustang
The automotive field has always intrigued the engineer inside of me. Since the age of 10 I have been involved in rebuilding engines and working on and with machinery.

A hobby of mine I have always carried on in some form or fashion. My first car, a 1972 Nova, is still in my driveway today. I have added several over the years and always enjoyed the mechanical aspects of all systems relating to the automobile. As a professional engineer there is nothing that drives us more than to learn how things tick. My drive in this field helped me to build an 11 sec street car, getting over 20 miles to the gallon and drive it to PINKS All-out.  That's right drove it, 60 miles one way raced for two days and drove it home on less than a tank of gas (stock 15 gal tank).  What a blast, my father and I both participated in the event in June of 2008 at Commerce Drag way outside of Atlanta.

My future project plans are to build a 1000hp pump gas, turbo, LQ9, a 6.0 liter Chevy truck engine. That will be going in the old Nova.

Here is a short list of some of my cars:

* 1972 Nova, owned since I was 15, drag raced at Bradenton FL.
* 1978 Camaro, a few, spent 5 years plus, on the dirt tracks in Western South Carolina.
* 1979 Corvette, never raced, but still own bought it when I was 21.
* 1988 SSP, Supercharged, Mustang, (ex-highway patrol car) (Car I entered in Pinks All-Out)
* 1986 Mustang GT, 5sp, 5.0l one of the nicest GT's from the 80's, first fulies and quick.

I have lots to say about the technology that went to building his car below. I've devoted the rest of this page to the technology I've put into my 88 Mustang and what I'd like to see in future projects.
 
 1988 Highway Patrol Mustang (PINKS All-Out Ride 06/2008)


Car Details

 
Engine
5.0 Liter 1988
Custom (Hogan Racing Intake setup)
80mm Throttle body setup, No EGR
Custom mounting on TB, Custom throttle and WOT Switch Brackets
Bosh 36lb Injectors
Mass Air Custom setup with C&L Meter
Powerdyne BD11A Supercharger
255lph BBK Fuel Pump
Nitrous System (w/dual 10lb Bottles warmers and controls)
Ice Box Aftercooler
Engine Management
 
A9L (factory engine management computer)
Tweecer RT (Piggybacked on A9L)
    - (Provides Complete Software Tuning and
       allows for 5 unique programs available at switch of knob)
CalCon (used to data log)
CalEdit  (used to edit engine computer binary files)
LC-1 Wideband
    - (Provides Exact Air/Fuel ratio and is data logged through
       the Tweecer)
Laptop
    - (Not required, but used frequently as I'm always upgrading)
MSD Digital 6 - Ignition
    - 2 step launch control
      (Wired into shifter button and clutch pedal latched relay.  This
       allows the 2 step and line-lock to be set with a single press
       of the shifter button and releases automatically when the clutch
       pedal is released.  See wiring diagram here)
EECAnalyzer Software (Many hours used to fine tune)
    - (Vital application used for fine tuning my setups)
Microsoft Excel
    - (Another vital tool in data log analysis)
Drivetrain
Tremec 3550 (5-Speed)
Steeda Shifter
Steal Bell housing (Scatter shield)
Spec Stage III Clutch
Ford Racing Aluminum Drive Shaft
8.8 Ford Racing 4.10 gears
Ford racing 5 lug conversion axles
Drive shaft safety loop
5-Lug conversion
Line lock on front wheels
     (Wired into shifter button and clutch pedal latched relay.  This
       allows the 2 step and line-lock to be set with a single press
       of the shifter button and releases automatically when the clutch
       pedal is released.  See wiring diagram here)
Suspension
 
Strange Engineering (10-way Adjustable) struts and shocks
Full Adjustable Coil-over conversion on front
Tubular lower control arms
Granatelli Rear-Lower Adjustable Control arms
Custom Modified (Solid) Rear-Upper Control Arms
Polyurethane Bushings
8-Point NHRA Approved Roll-Bar (Welded in)
Strut-Tower Brace
BBK Adjustable Caster/Camper plates
 
Inside
 
Buttons and switches, Everyone has them but these buttons multi-task.
Used lighted activation switches, flip to turn on,
      lights up when activated.  (Master/Line Lock/2 Step)
All nitrous activation is double wired through clutch and
      WOT switch wiring.
Clutch latching setup and Manual activation.
      - One switch on shifter does the following:
         1) Holds Front line lock manually when doing burn-out
         2) Sets Line Lock when fully staged *
         3) Sets 2-step when fully staged *

* These two functions are tied into the adjustable clutch switch which
  allows activates and HOLDS the power to these devices through a relay
  which releases at an adjustable point when releasing the clutch pedal.

Extra Nitrous Bottle (Fully wired and plumed, available to turn when
    bottle in trunk fails or is empty.)
Remote Bottle opener for N20 Bottle in trunk
Heater Switch activates heaters on N20 Bottles
Carbeau Racing Seats
5-point Driver harness
Adjustable Shift Lite
Custom Mounted Boost Gauge
Custom Mounted O2 A/F Ratio Gauge
Outside
 
Just a few warnings:
A little fire
And a little attitude
 
Wiring Diagrams
Nitrous Heaters (warming blankets)

Nitrous System (Sorry so slopy, did this one day of the install, have not had time to redo)


Custom Built from Multiple sources and Links found below
Rear Latching Starter solenoid
Nitrous
N20 All plumed in braded SS AN lines
Remote Electronic Bottle opener on truck mounted bottle
Car bottle opens manualy
Both bottles on relay operated thrmostatic heaters
System is wired with the following safety devices:

     - WOT Switch (Will not activate unless Wide Open Throttle)
     - Clutch Engaged Switch (Above WOT is wired through a normally
       open switch on the clutch, if you hit the clutch the N20 goes off.)
     - Digital Window Switch (Allows for predefined N20 Activation points
       both on and off.  Nitrous is currently activated 200rpm above launch
       and turned off 200 before max rev on Ditigital 6)

 
Other Details
Race Prepping (All bolts have been cleaned and lock tight applied)
Every hose is clamped
All wiring is soldered and shrink tubed
Street Ability
    - (Drove it 60 miles to Pinks All-Out taping,
       raced two days and drove home on a tank of gas
Does not have a Radio but does have A/C :)
Custom N20 Jumper for warming bottles in pits:
Tuning Details
Details of Main Tuning Challanges and Tribulations: See Below: Tuning

 
 
 Clutch Pedal Latched Relay
It took me several attempts to find detailed information about doing a latched relay this way.  I thought I'd share what I found and how I ended up doing it.

In finaly getting this nailed down I've wired two vehicles this way and it works out really nice.

This setup allows the clutch pedal (or break pedal on automatic) to be the release for both a 2-step and front wheel line lock system.

They are both activated through a single button on the shifter and can be optional used manually and seperate of each other.

For example:

1) The Burn Out

When doing my burn out, I turn on button A (the main activation button) and button C (line lock on) press both the clutch and break bedal in and hold the button on my shifter.

I now can release the clutch and nail the gas while continuing to hold the button on the shiter (Manually holding the front breaks).

When I'm done with the tire smoke I release the button and ride it out.

2) Full Stage/Launch Mode

Turn on buttons A, B and C.  Once full staged, with clutch pedal and brake pedal depressed HIT THE BUTTON. 

Thats it, your ready to go, you can release the button.  When ready let up on the clutch and the switch on the clutch pedal will release the 2-step and line lock and also feed power to the N20 activation WOT switch if on.
 Tuning

I have spent major amount of research time understanding how and what the engine control computer needs to provide an appropriate fuel mixture and timing at any given engine load/power requirement.  That's basically what it boils down to fuel and timing.  However in order for a computer to determine these two simple objectives it must have information as to what the engine it is controlling is and what it is trying to do.

The computers function in relation to engine management is to determine the fuel and spark requirements.  This is done through a set of defined parameters known about the engine (i.e.: engine displacement, injector size, etc.) and a method of collecting live real-time data about what the engine is doing right now.  This data collection is the same or similar on most engine management systems, a series of sensors (i.e.: Throttle position sensor, crank position sensors, cam position sensors, etc.).

The computer uses the real-time data to determine the load requirements being demand of the engine.  For example, an engine sitting in a car not running is under zero (0) load, hook it to the Empire State building and open it wide open throttle the engine would be under full load (100%).

With that said, I'm going to get real technical about this then I'm going to do a write up on how I think it could be improved upon.

Let me start off by saying your technical understanding of an internal combustion engine really plays a key in how difficult the learning curve is.  I'm going to attempt to describe it from my background of building and tuning carbureted engines.  To me it makes since to have a better understanding of what ever your managing then the computer you’re trying to train.

The tuning on my supercharged 88 SSP, custom fuel injected and nitrous breathing street car has been a real learning experience.  Let me go through the process I took to make this project work.

Basic Goals for my Mustang:

·         Maintain complete street drivability car

·         Keep it clean and neat on the outside

·         Make it fast

·         Have flexibility and adjustability from the engine to the tires and all between.

·         Ability to adjust setup for street / drag / road racing.

I really wanted to maintain that nice idle of a 5.0 liter mustang.  Which meant there was going to be a need for power adders.  When I first purchased the mustang, it came equipped with a basic 5.0/stock intake/stock 5 speed and a Powerdyne Supercharger.  The tuning was all stock with a manual fuel management unit (FMU) adding extra fuel based on boost.

This didn’t seem adequate enough for me. It seemed the first step was to enlarge the injectors and remove the FMU.  That started it for me.  I started to determine how large of injectors I needed and what I needed to control / modify the computer to use them.

In comes the Tweecer RT, an excellent tool for the money.  I can not complain about its reliability to get the job done.  The Tweecer RT will really allow you to modify all aspects of the engine management for you tuning needs.  The trick is you have to know what you need to modify.  Well lets start their, a list of modifications, first your engine and mechanical systems then how to tell the computer what you have.

My Setup:

·         5.0 Liter bored .30 over for a total displacement of 306ci.

·         MSD Digital 6 ignition

·         BBK 255lph fuel pump

·         36lb/hr Bosch injectors

·         C&L 73mm Mass Air Sensor with 36lb tube

·         Centrifugal belt driven supercharger making 7lb boost @ 5500

·         After cooler (air to liquid)

·         Hogan Racing Sheet Aluminum intake (GT40 Base)

Tuning:

Key points

·         Air Intake

·         Boost Compensation

·         Injector sizes

·         Timing

Air intake is one of the main functions of the computer which you will benefit greatly in making sure the computer has the best information possible.  Without it everything it calculates is off.

On computer controlled engine the amount of air coming to the engine is monitored through one of two standard systems Speed Density and Mass Air.  A speed density system uses a set of given parameters relative to engine speed and the density of the air to determine how much air is inside the engine at any given speed.  On the other hand a Mass Air system reads the amount of air coming into the intake tract.  With either system the computer must have accurate information about the amount of air in the engine.

My Mustang came from the factory as a speed density system; however a popular change over to a Mass Air system had already been preformed for me.  The Mass Air system provides a little more flexibility and adjustability for minor mechanical enhancements to the entire engine drive train.

The Mass Air System consist of two major parts a sensor and a defined set of data that tells the computer how to read the sensor.  The sensor itself doesn’t know how to read the air; it just provides a voltage signal back to the computer that is directly proportional to the amount of air that is traveling through it.

The relationship of {voltage returned from sensor}={amount of air going through sensor} is how the computer determines how much gas to add to it.  If this relationship is off or not defined correctly then the computer will not add the appropriate amount of gas.  This relationship is defined in the computer as a Mass Air Transfer table.  Where as for any given voltage the sensor sends to the computer the computer knows X amount of air is coming through it.

 

Mass Air Transfer Table Stock (A9L):



The grid and graph above show a standard Mass Air Transfer table from a stock A9L ford EEC. Looking at this grid you’ll see two columns of numbers; Volts and kg/hr also displayed on the graph. This grid allows the computer to know how much air in kg/hr (kilograms per hour). The sensor feeds back the voltage and the computer looks it up on this chart to determine how much air is going into the engine. The key thing here is that the Mass air sensor you use determines what these numbers should be.

To start you should determine what the manufacture states as a transfer rate and go from their. Depending on your system you’ll need to enter this data into your engine management computer. After which these numbers can be fine tuned using your data logging and analysis skills.

Using many data logs and EECAnalyzer my Mass Air Transfer on my Mustang looks like:



The obvious difference here is the maximum amount of air going into the engine at the top of the graph.  The stock a9l computer only allowed for a maximum of 835 kg/hr of air.  That was all the computer though was coming into the engine when the sensor was returning its maximum voltage (usually somewhere around 4.9??).

The changes made here allow my computer to correctly add the amount of fuel for the correct amount of air.  Prior to these changes the FMU was artificially adding air based on a boost referenced vacuum line.  Correcting the MAF Transfer table allows the computer to handle the fuel requirements; this will provide a much smoother and more controlled air fuel mixture over using a static mechanical method.

Improvements:  Air sensors are not rocket science, however in order to achieve the above results it seemed like it.  I went around the world trying to get a good understanding of what I needed to do to provide the computer with this accurate information.  Not until I went through many trial and errors did I achieve the results I needed.  However, it seems like several steps could be made simpler. 

MAF Manufactures listen up please give us a MAF Sensor that will:

1) Calibrate:
     - Recalibrate button
     - allow me to hook it up to a laptop and calibrate it.

2) Output
     - Allow me to view the voltage with a display unit or laptop.

3) Provide the consumer a means of fitting the correct MAF/Calibration to their application.


Injector Sizes:

Once the computer has determined to amount of air going into the engine it uses some other modifiers and determines the amount of fuel to add. This is then translated to the fuel injectors to deliver the fuel. The injectors are rated to flow a certain amount of fuel and the computer must know this information. For my purposes the ford EEC uses two base values to determine the size of the fuel injectors called “Injector Slope High” and “Injector Slope Low”. These two values are used at different times during the engines load range. The “Injector Slope Low” is used during a low period of load or less requirements on the engine (i.e.: idle up to a set amount of load). This setting basically cuts back the injectors under low load periods and allows for better fuel economy, one of my goals. The other setting “Injector Slop High” is used when low isn’t. This is more to the actual size of your injector rating.

Setting the Injector sizes in my setup required a little tweaking from recommended numbers to get the final results I was looking for. I started by setting my high slops at 36 and low at 60. This was finally resolved to 34.7893 and 79.0613 for my setup after many sessions of logging and analysis.

These numbers will vary from system to system, differences in fuel delivery to the injectors, pressure differences from manufacture ratings, etc. Keep in mind that the manufacture rates a fuel injector at a certain flow rate per hour based on a given fuel pressure on the input side of the injector. If you raise this given fuel pressure the injector will flow more than the manufacture rated it. Likewise the injector will flow less if the input pressure is less than rated.



To be Continued...