Properly detailing your engine...
Properly detailing your engine compartment is no easy task, but the results are well worth it. After removing all of the wiring and components from the four walls of the bay, you can wash and degrease them, and then sand them with 600-grit sandpaper. We actually used some red flexible sanding pads from the local parts store.
Unfortunately for most late-model Mustang owners, the factory didn't do a great job with the paint in the engine compartment. And while we spend most of our resources on go-fast parts and the exterior of the car, sooner or later we turn to the engine compartment, which is often left in disarray. In this article, we're going to show you how to tidy up the engine bay of a Fox-body Mustang so it looks as good under the hood as it does on the outside.
The first thing you'll need to do is lay out some goals of what you want to accomplish and what you can do within your budget. It's easy to get carried away under the hood, but you'll want to realistically figure out what you can afford to put into the makeover, and equally important is how much time you're willing to spend keeping it clean and shiny once the transformation is complete, as well as how much time you have to complete the job.
Our subject vehicle has graced the pages of MM&FF on numerous occasions in tech articles of all sorts. The ProCharged Pony put out 580 rwhp, and a repaint several years ago had it looking great in its Twilight Blue Metallic and Argent hues. The problem was that the engine compartment didn't look any better than your average daily driver. As it happened, we had to pull the cylinder heads to change the head gaskets, and decided that it would be a great time to give the engine bay a full detail.
Having the engine down to the short-block makes it a lot easier to get to the framerails, firewall, and transmission tunnel to sand them and shoot some paint on them. With all of the accessory brackets off of the engine, it was also a good time to paint and polish them as well. Having the motor apart or out of the car is not necessary to painting the engine bay, as we have seen firsthand, but it sure makes it easier. If you're planning on welding up all of the factory holes in the fender aprons, we highly recommend pulling the motor to do so.
We opted not to fill the holes in the aprons, but we did want to hide the engine harnesses as much as we could. With the relatively dark color that we'd be using, the holes don't stand out nearly as much as they do on a brightly colored car. Plus, we expected our polished supercharger and other components to garner the most attention.
As with any paint job, there are varying degrees of perfection that can be attained, so consider how much you drive the car, where you drive it, and how much time you plan on spending under the hood cleaning things, before you start laying on the primer and paint. Our car, while a recreational third vehicle, was driven often on the highways and always treated as a regular street car, but we wanted to be able to open the hood at the local cruise-in and not be ashamed.
After the engine had been torn down to the short-block, we removed all of the wiring harnesses from the fenders and removed the associated components that were mounted to the fender aprons. With the engine bay down to just the sheetmetal, we picked up a bunch of red Scotchbrite sanding pads at the local auto parts store, degreased the engine compartment, and went to work sanding.
We retained the services of Mark Johnson to lay down the primer, sealer, and basecoat/clearcoats. Johnson is a collision specialist by trade, and he was also the guy who painted ProCharged Pony's exterior, which was still looking great after 10 years. After Johnson set the paint gun down, we left the freshly painted engine bay to dry for about a week, as we didn't have the opportunity to let it bake in an oven. After that, we started hiding the left- and righthand wiring harnesses up under the fenders.

This doesn't look like a 600hp...

This doesn't look like a 600hp engine to you does it? We didn't think so, and the fact that we had to tear down the engine for some repairs made the decision all that easier.

This mess just had to go,...

This mess just had to go, and it will. It'll all be hidden inside the inner fender.

Everything here, except for...

Everything here, except for the fuel-system components, was getting relocated as well. If you're going to be filling in the holes in the sheetmetal, be sure to mark any that you may need to keep, such as the fuel-system mounting holes.

Here, our painter Mark Johnson...

Here, our painter Mark Johnson has laid down the primer/sealer prior to applying the base and clearcoats.

Our new Twilight Metallic...

Our new Twilight Metallic Blue paint has been cured, and we've started unwrapping the wiring harnesses and other components to begin their relocation.

While the main harness at...

While the main harness at the back would normally be held in place at the sheetmetal seem sticking out, we tucked ours down behind the back of the engine. We've seen people drop the air conditioning dryer down and hide the A/C line behind the intake too, but we wanted to maintain access to our fuel system so we opted not to do that.

The passenger-side harness...

The passenger-side harness is routed through this factory opening at the back of the inner fender apron. It's much easier when you don't have a heavy gauge stereo wire trying to fit through there also, but we made it happen, and we didn't have to lengthen any wires.

The driver-side harness is...

The driver-side harness is also routed through a hole in the back, though this one is less accessible due to the brake booster. Our situation was further complicated given we had the larger SN-95 booster from the 2300-K brake upgrade. Still, the harness fit through and we didn't have to lengthen any wires.

Two easy ways to dress up...

Two easy ways to dress up any engine compartment are shiny headers and valve covers. These headers are ceramic-coated shorty headers from BBK Performance. They are by far the best fitting equal-length shorty headers we have installed, and dropped right in without any drama. We opted for the ceramic finish, as it tends to stay nice longer than the chrome versions. The valve covers are chrome-plated stockers from Ford Racing Performance Parts. Strictly a remove and replace operation with these.
Before you go through with this, you'll want to consider how much you work on the car and how often you use it. Hiding the harnesses means your access to things like the starter solenoid, switched 12-volt lead, mass air meter harness, and such will be limited. In fact, you'll need to pull the front wheels and inner fender liners out to get to them.
We've heard, and seen, people hide the rear harness, which travels across the firewall at the back of the engine. This usually involves some fabrication to get the harness to sit in the cowl area under the vent. It definitely cleans up the engine bay, but you'll need to cut some holes in the firewall to fish the harness in there. You'll most likely need to lengthen wires, and you have to have a way to keep the harness dry, as it'll be exposed to the elements in the cowl. Even though you may not drive your Pony in the rain, a simple car wash may be all it takes for the harness to short out. We simply pulled the harness from its plastic fasteners that hold it to the firewall, and tucked it down behind the engine.
With some careful planning and maneuvering, we were able to snake the right and left harnesses up in the fenderwells without lengthening any of them. We've heard of some people having to add wire to the headlight harnesses, but ours fit just right. With the wiring complete, we turned our attention toward the engine parts. As the motor went back together, we opted to replace our powdercoated Edelbrock Performer intake manifold with a polished Edelbrock Performer RPM II intake (PN 71231). The RPM II manifold is better suited to our stroked and supercharged combo, and the polished finish really lights up the engine compartment. Polished aluminum will require some maintenance, with frequent polishing a requirement to keep the finish from dulling. Water spots can also be troublesome, but if you keep it polished, they should come out fairly easily.
While you could spend some time--quite a bit in fact--sanding and buffing the factory aluminum valve covers, a much easier way to go about it is to order a set of chrome-plated covers (PN M-6582-D302) from Ford Racing Performance Parts. They have a slightly different finish compared to the polished intake, but they look great and save you from a lot of hand labor. Things like the air conditioning compressor bracket and alternator bracket were sanded and painted to give a fresh, shiny look. We also polished the supercharger brackets, since they were made from aluminum and had a relatively smooth finish to start with.
Getting down to the smallest of details, UPR provided us with its billet coolant reservoir, brake fluid, and window motor caps, along with its polished stainless radiator cover. We sprung for a chrome hood prop rod from Late Model Restoration, but you may want to go with a slightly cleaner look and get the gas struts to hold up your bonnet. These small items end up making a big impact in the overall look of your engine compartment.
Renovating your engine bay is a lot of work, but then any finish/detail work is. The good thing is your ride will stand above the rest because you went the extra mile that the other guy didn't.

For the intake manifold, we...

For the intake manifold, we opted to make both a performance, and an appearance upgrade with the Edelbrock Performer RPM II. The RPM II has an increased RPM range over its Performer sibling that we were using, and the polished finish is just what this engine bay needed.

Simple details like this timing...

Simple details like this timing pointer (PN M-6023-B351) from Ford Racing shows onlookers that you've put a lot of effort into this job.

We repainted the water pump...

We repainted the water pump and associated brackets to give them a new appearance. The supercharger brackets were hand polished.

Here you can see the driver...

Here you can see the driver side wiring as it has been mounted in the inner fender. You need to mount it high enough so the fender liner will fit back in.

The passenger side is routed...

The passenger side is routed in the same manner as the driver side. You can even mount the charcoal canister up here too. You just need to lengthen the vacuum hoses.

Wire looms are an age-old...

Wire looms are an age-old way of cleaning up your engine compartment, and if you have a pushrod motor, these should be job one. Part number M-12297-B14 will get you these nice wire loom holders from Ford Racing Performance Parts.

Some wires will need to reappear,...

Some wires will need to reappear, but that doesn't mean they can't be hidden until you need them. This ground wire used to be mounted up on top where the prop rod is, but relocating it offered a cleaner, yet still effective, look.

After a bit of polishing to...

After a bit of polishing to the top of the aluminum radiator, our makeover is complete. Yes, we could have gone quite a bit further, but we struck a balance between maintenance and appearance, that leaves us proud to display our supercharged powerplant anywhere, anytime.