KJ Jones Senior Technical Editor
August 1, 2008
Photos By: Hannah Montoya, Greg Montoya
Dart Machinery's new Iron Eagle cylinder heads highlight Greg Montoya's H/C/I swap. The cast-iron heads (PN 13301182; $1,053.95) feature beautifully radiused, 1.175-inch wide x 2.050-inch tall, 180cc intake ports that flow 247 cfm at 0.500-inch lift.

Horse Sense: A 5.0 H/C/I swap really isn't an overwhelming ordeal for the average mechanically adept enthusiast who has a good understanding of how to take parts off and put them back on. As it is with anything else that involves working with an engine, the number-one rule of thumb to follow is: Take your time. For great step-by-step details on the H/C/I-swap procedures themselves, grab a Haynes Automotive Repair manual for Ford engines (www.haynes.com). It's thorough, it has pictures, and it's exactly what you need for clearing up any confusion you have about the job.

Keeping track of all the high-flowing cylinder heads, high-revving camshafts, and high-performance cold-air systems available for Two-, Three-, and Four-Valve 'Stangs is no easy task in our predominately modular world. Manufacturers are constantly offering us new technology for 4.6-powered Mustangs, so you can imagine how excited OG 'Stangbangers like your tech editor and Editor Steve Turner get when we hear about anything new for good ol' 5.0-liter engines-the bullets that helped lay the groundwork for the Mustang madness we all thrive on today.

Not bad, for DIY. That's right: This is the stock 5.0 that was nestled between the front fenders of Greg's 'Stang at the outset of our project. Greg built this engine himself after scoring the car as a roller in a multilevel trade deal that rivals that of professional athletes. We're still trying to figure out the details, but based on the appearance of the clean, white '89 GT, the car will be a cool street cruiser, and hopefully a Pony that will hold its own on the track as well.

Dart Machinery is recognized by Mustang racers and enthusiasts as the maker of the Iron Eagle series of 302 and 351W engine blocks. The company is better known for its blocks than for producing small-block Ford cylinder heads way back in 'Stangbanging's early years.

That's right: cylinder heads-and cast-iron cylinder heads, at that. Dart's Windsor and Windsor Junior heads were among the limited number of must-have Fox Mustang performance parts back in the day. The 5.0 in your tech editor's nitrous-injected '84 GT sported a pair of Juniors that helped carry the street/strip 'Stang to 10-second e.t.'s in the mid '90s.

The heads' composition made them much heavier than the all-hallowed aluminum heads that have ruled the 5.0 roost since the mid-to-late '90s. Despite that, high-volume ports, larger valves, and combustion chamber improvements (over Ford's E7TEs) enabled Dart's heads to flow a lot of air. When combined with camshafts and intake manifolds that complement their capabilities, they sent many street- and drag-race 'Stangs into the low-e.t. zone for a relatively small monetary and time investment.

Fast-forward to today, and Dart is once again giving us a good reason to be interested in its cylinder heads. No, there hasn't been any improvement in its Pro-1 CNC aluminum heads. What we're amped about are Dart's new cast-iron heads, which-similar to its popular blocks-are also called Iron Eagle.

Marking the rotor's position at top dead center is an important disassembly procedure when you're swapping camshafts and intake manifolds. The distributor must be removed unless you're only changing the intake manifold. Making this reference ensures the distributor is reinstalled at the same position in the timing sequence, and the engine should fire right up.

Once again we're exploring the performance capabilities of heads/cam/intake combinations for 5.0 Mustangs. However, unlike other reports we've done on this topic that feature H/C/I packages offered by manufacturers, we've compiled pieces from individual companies we think make up a compatible, affordable package that will do well on a stock Fox Mustang engine.

The Iron Eagles are flying at the front of this effort, along with a street/strip N-41 hydraulic-roller camshaft from Anderson Ford Motorsport and high-flowing intake components (SSI Series manifold, 70mm throttle body, and a cold-air induction system) from BBK Performance.

We know your thirst lies in how much power the assortment makes, so we won't dawdle too much on the installation of this bolt-on package. The accompanying photos and captions illustrate highlights and notes on the install from our buddy Greg Montoya, a do-it-yourself 'Stangbanger who was ready to take the bone-stock powerplant (save for short-tube headers) in his '89 Mustang GT to a budget-friendly but better level of performance.

Greg handled the parts swapping in a few evenings at his home garage after work. As you'll see when you read further, the H/C/I package we selected proved to be well worth his time and the impressively small monetary investments.