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As Ford updated the Mustang Models it also updated its components, when I go to the parts store I sometimes find what I'm buying doesn't look like the part I'm replacing. This section is intended to list the new replacement parts and to aid in compatibility of different parts for different years. As this site is new, I know there must be some errors and years that are off. Please E-mail me with suggestions, corrections or more info for this site at SPARKPLUGS@MAILCITY.COM . Thanks...


87-93 Front Brake Hoses

Before and including 1986 the flex brake hose was all rubber. In 1987 it was changed to part rubber and part bent pipe. Still later (Not sure when) Ford changed the design again. I found this out after I had everything apart. The new hose has a different fitting shape to insert into a new bracket opening that holds it in place. The old hose and its opening was star shaped, while the new shape is round with a notch.

So now you can plan ahead (had to order new bracket from Dealer, didn't have it in stock) or I guess you can drill the bracket out. I would spend the $5 than to have the hose jump around in the busted bracket and eventually break.



Explorer Intake

There are plenty of aftermarket intakes, some from Ford: GT40 & Cobra intakes, & others from Edelbrock & Saleen. Basically all better than the restrictive stock intake. Lately there's more info that Explorer Intake manifolds from 94-98 5.0 V8's will fit (with minor work) & improve lower end torque Now It's performance is not as good as the next best intake the Cobra, but I believe the cost is near half. Go see this website BLK90LX's Mustang Page for info on this intake & how to install it.
More info to come....





You can also use the heads of a '96 up Explorer, it is said that the 1996 Explorers use the GT40 Heads (like in the 93 Cobra). Check out this site for more info...GT40 Heads..



Supercharging Your mustang can be done safely as long as you don't over do it ...

A stock (1986-94) 5.0 has 9:1 compression, it can safely handle a low output supercharger with about 6 to 8 pounds of boost, while running 92 or higher octane. Going higher in boost could result in detonation (pinging) and some nice holes in your pistons.

There is also another matter to keep in mind when planning to get a supercharger, some are designed to give its boost or increase Lower end torque, while others increase Higher end torque. With a lower end increase you wouldn't have to raise the RPM's as high to get a good launch.

Owners of Speed Density 5.0's (87-88) say it is possible to install the low boost superchargers to Speed Density cars with no idle problems.

Higher boosts require more fuel! Depending on what your doing you may need to get larger injectors & higher flow fuel pump.

The kits will come with all needed hardware, Some kits will relocate the alternator, & most cost in the $2800 to 4000 range.

Before you supercharge your motor install a less restrictive exhaust+ headers & at least cat=back system.

Most of all... this is info for the beginner that I have acquired, learn all the info you can on your specific motor setup & ask your mechanic, the supercharger manufacturer, & helpful mustangers at places such as to make your decisions...


Speed Density VS. Mass Air
Speed Density:
Mass Air:

All 1986-1988 Mustang 5.0's were equip. with a Speed Density computer system.
- The air entering the system is not directly measured but "guessed" buy RPM & various other sensors then that data checked against a chart of values.

- Since the computer is doing everything "by the book" it will not adjust well, or at all to major modifications, especially larger cams. It has no way to adjust because it has a predetermined set of values to follow

-SD cars are known to be faster than mass air cars due to the addition of more emission concerns, restrictive mass air meter, & funny enough by guessing the SD computer guesses in favor of speed. Actually it runs leaner, or was that richer???, I have to find out again...

Mass Air 1989 & up has a Mass Air Sensor (on air inlet tube right after air filter) that directly measures the amount of air flowing into the motor.

- Because this system knows exactly how much air it's getting will adapt to any motor modification, including large cam, supercharger, larger intake.

-The mass air meter's opening & throttle body is smaller (55mm) than the SD's Throttle body 60mm.


Advancing Timing

The lowest cost performance increase you can do to your motor is to increase the timing. Drivers notice a noticeable increase in lower torque with as little as a 2 degree increase.
Now the bad news the factory setting for the 5.0 is 10, which allows you to run low octane gas. Bumping the timing up will require you to use at least 92 octane.
Mustang owners have safely bumped timing up to 14.
So keep in mind that increasing the timing can cause detonation that will blow holes in pistons & other problems, it is recommended to go up 2 degrees & listen for detonation. Also keep in mind that cooler weather will not produce as much detonation as hot weather will. You might get away with it in the winter, but will pay for it in the summer...I wouldn't go over a setting of 13 degrees.

Note: Advancing timing on your motor will increase its emissions &
may not pass emissions tests.


Alternator 130 3G Upgrade

Most of the 86-93 stock alternators are junk (75 amps), not putting enough voltage out when idling. Even the connector to the alternator is known to cause fires(very rare though). The solution is to install Ford's new 130A 3G Alternator (from the 1994-95 V8 Mustang GT & Cobras only,not V6). It's better designed, will last longer, and has plenty of power to idle and have all the accessories on. This will require you to buy a new Alt around $130, and make new connections, it should fit with no problems other then grinding a small portion of its bracket. Follow the directions ,you need to replace the stock alt wire with a thicker gauge wire that can support higher amps. Go to my LINKS PAGE and visit The Corral (in its tech section) & The 130A Upgrade project, & Monte-Smith's Webpage links.
Be sure to change the smaller gauge stock alternator wire with a thicker gauge as per the instructions on Monte-Smith's Webpage!



Outer Tie Rod Ends

Around 91-94? Ford changed the Outer Tie Rod Ends (longer ends) to help keep the Rods (steering linkage) parallel with the lower control arms, reducing bumpsteer. I believe the length difference is not the rod to the rack but the smaller pivoting stud that bolts on to the spindle. I believe that You have to ask specifically for these or you will get the shorter (original) ones that came with you 86-91 stang. Unfortunately I didn't know this last year when I replaced all inner & outer tie rod ends (tried to reduce annoying bumpsteer). You will need to adjust the toe (alignment-length from rack to spindle). I don't have any proof of the benefits but it seems to be recommended, on all the mustang tech sites, to upgrade to the later rods.



Valve Cover Gaskets

I don't know exactly when, but Ford has upgraded the valve cover gaskets for the 5.0 to a metal design. Its a solid (rigid) metal gasket with rubber on the inside. The reason for this is the 5.0 has too much of a gap between valve cover bolts and the rubber, or cork gaskets would tend to move or break where the gaps were. The Metal gasket costs around $35 for both sides and is long lasting. I would think you could remove the valve covers many times while not having to replace this gasket.



Power Window slow/sticks

You push the window switch up, (the window might go halfway up seem to shift) then it takes a year to close. First thing is to check the rod that the window is sliding up & down on. Usually the grease deteriorates. Unfortunately you have to take the interior door cover off. Clean off the old grease then put new grease on the rod & diagonal track. Don't use penetrating oil instead of greasing, it will just clean the old grease off, dry up & leave no protection. Also check that the 3 bolts holding the window motor are tight.



Fuel Pump Connection (Submitted)

After removing the gas tank to replace the no longer functioning fuel pump, a Mustanger noticed that a fuel pump wire had became burned. I don't think (& hope not) that this is a common problem but is worth looking at if you have to remove the fuel tank...

My complaint is of the fuel pump connection on the top of the tank where the fuel lines connect.
I had changed the fuel pump because I thought it was bad , it tested positive for power going to it. It turned out that the connections came loose inside, & the wire got hot, visible burn on the red connector. There's 2 prongs on the top of the fuel pump male end of the connector/retainer assy. 1 came loose from heat. I cleaned all the grease out and used a epoxy to hold the prong up so it would make contact.
It's working for 1.5 years now. TIP ( use a heat gun to solidify the epoxy(marinetex is what I used).
...Tip Submitted by Gino



Rear Disk Conversion

Thinking of upgrading the rear drums in your Mustang to Disks?

You can buy Rear disk Conversion kits, they will cost more, but you will get everything needed & everything will be new or rebuilt. Some companies are Aerospace, Stainless Steel Brake Corp, Wilwood, and FRPP. (look in Mustang Mags)

Most conversions (like Ford Motorsports/or Racing whatever their calling it now) will change your axle to a 5 lug setup.
-You will also need a bigger Master Cylinder


If you want to keep your stock (or any) 4 lug rims you will have to find a 4 lug specific kit.

OR you can assemble a kit yourself for around $250.
You will need rear axle parts from 87-88 Turbo Coupes.
NOTE: Turbo Coupe Axles are slightly longer than your Mustangs & you will have to use the T-Birds caliper mounting brackets if you use the T/C Axle.

You will have to buy brackets from SSB to fit on the Mustang's axle
(part numbers for the brackets from SSB Corp is #A2418 and #A2419.).

The E-brake cables are '93 Cobra. Wagner part #:F1324400

Helpful Link ->
4 Lug Rear Disk Conversion

Helpful Link ->
go to its tech section.
Detailed, Motorsport Kit
5 Lug Rear Disk Conversion

More info or sites when I can find them , If you have done this conversion please share with us your experience ...Spark Plug




1986-1992 Mustang 5.0's have Forged Pistons
1993-up (including Cobra) 5.0's have hypereutectic Pistons

- Forged pistons are very strong & are recommended for High Compression, Turbo & Supercharged motors

- Hypers
are less strong but perfect for stock applications, cost less, slightly lighter, & less oil bypass.






- 1987-93 5.0 H.O Injectors are 19#Lb

- Non-H.O. 5.0's use 16#Lb injectors
- 1983-86 TurboCoupe 2.3's use 30#lb

- 1987-88 SVO & T/C use 35#lb &/or 36#lb.

- 1987-93 Stock 2.3 use ??#Lb.

Injector Color Codes

Orange (Stock 5.0 HO): 19#
Lt. Blue: 24#
Red: 30#
Dk. Blue: 36#
Lt. Green: 42



A Note from Spark Plug...

The purpose of this section (& this website) is to gather information from various sources to help the Mustang Owner stay informed with changes & Useful information all in one place.

There is plenty of useful info on the web but most is hard to find, it turns into a guessing game when you get just a mess of links to choose from, I try to include as many helpful links to sites for specific topics as I can find, the more info & opinions the better.

One thing that bothered me was, as great as the Tech message sites were questions that were answered (in detail) would be erased after a while & that great info was lost... So I search through many questions on sites, magazines & swap meets to get a permanent database of info. And any of your tips would be helpful.

Keep in mind that Some info here & other sites are opinions & 3rd party info that has been compiled to keep you informed, but always keep in mind that this is to help inform you in your decision process, always ask a technician or mechanic before you start pulling out your toolbox...

I hope this site can help you maintain your Mustang
for years of enjoyment.
...Spark Plug