Posted by Anderson Ford Motorsports on December 01, 2017
The Mod V8 may have been looked down on when it first reached the Mustang in 1996, but over 14 years, engineers found new ways to squeeze more power out of this overhead cam engine. What’s the differences between these versions of the engine, and which ones are best for building a project car?
Why is it called a “Mod” motor?
The nickname is short for “modular.” The overhead cam V8s used in the Mustang were part of a new way for Ford to build different engines ranging from Duratec V6’s to Aston Martin V12s using similar tooling to cut costs. Aside this shared design aspect, these motors don’t share much in common with each other.
The 4.6l Mod Motor in the Mustang
The first Mod motor, an iron block 4.6 liter with two valves per cylinder, debuted in the 1991 Town Car, offering better performance and fuel economy over the old 5.0l small block. This engine made its way into the Mustang in 1996. While horsepower was the same as the old High Output 5.0, low end torque was lacking and it had very little aftermarket support, giving the engine a bad reputation early on.
In 1999, Ford came out with the Performance Improvement (P.I.) cylinder head. Changes to cam timing, intake runners and head design increased power from 225 to 260 hp. This engine was used in the Mustang from ‘99 to ‘04 and Panther platform cars including the Crown Victoria and Grand Marquis from ‘01 until they left production.
In 2005, a new three valve per cylinder head was introduced, improving cylinder head flow and increasing output to 300 hp.
The DOHC 4.6l
Cobras got a dual overhead cam engine with four valves per cylinder in 1996. This engine uses an aluminum block, swirl port head design and Intake Manifold Runner Control (IMRC) that uses two sets of intake runners. By only opening the second set of runners at high RPM, intake velocity is maintained to keep power up through the rev range. These “B port” heads were used until 1998 and were rated at 305 hp. From ‘99 to ‘01, the engine used “C port” tumble port heads and dropped IMRC, increasing output to 320 hp. Versions of the DOHC engine were also used in the Mach One, Mercury Marauder, Lincoln Aviator and Lincoln Mark VIII. In ‘03 and ‘04, the DOHC 4.6l returned to the Cobra with an iron block, supercharger and a freer flowing exhaust, developing 390 hp.
The 5.4l Mod Motor
Like the 4.6l, this larger displacement motor received different head designs through its lifetime, including two, three and four valve heads. Mostly used in trucks and SUVs, it found its way into the 2000 Cobra R and 2007-09 Mustang GT500. DOHC engines were used in Lincoln Navigators from ‘99 to ‘04 with a rated 300 hp, while the ‘99-04 Lighting uses a SOHC and supercharger to produce 360-380 hp.
The issues with these engines are similar to those faced when dropping a 351W into a Mustang that was equipped with the 5.0: the added stroke length makes the motor taller and wider, causing fitment issues, while the low end torque-focused stock heads limit performance. That said, the accessory mounts and oil pan are identical, making it an easier swap than the small block.
The Mod Motor Today
Like any new engine, it took a while for tuners and aftermarket manufacturers to figure out how to get more power out of this design. Its biggest weakness is head flow, which has been addressed with both aftermarket and Ford’s own head designs. The iron block and bottom end are extremely strong, letting these engines handle power that would break a stock 5.0.
The aluminum blocks used in the Cobras came in several versions including Teksid-built blocks used in ‘96-’96 Cobras and ‘93-’98 Mari VIII’s, Windsor Aluminum Plant (WAP) blocks used from 2001 to 2004 and improved WAP used with 3 valve heads starting in 2005. The Teksid is the strongest of these, but problems with the other blocks only show up when making power that is rarely seen outside of purpose-built dragsters.
The Coyote used in current Mustangs is essentially a heavily updated version of the Mod motor, making it another swap option. Ford Racing’s new Aluminator use the Coyote’s parts, resulting in a naturally aspirated engine based on the flat plane crank Shelby 5.2l producing 580 hp and a low compression motor designed to work with a supercharger.
Get More Power from Your Mod Motor with Help from Anderson Ford Motorsport
From our in-house designed intakes to complete crate engines, if it improves your Mustang’s performance, you can get it from Anderson Ford Motorsport. We’ve been working on these motors since they were introduced, so we know what Ford Mustang Performance parts works.
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