In 1996, Mustang GT and Cobra got their first 4.6L SOHC and DOHC engines. In 2005, Mustang GT got 3-Valve SOHC power. Isn't it time you knew more about the engine Ford spent more than $1 billion developing to make Mustang the most advanced pony car ever?
Here are some of the Ford vehicles that use 4.6L Modular engines:
4.6L SOHC Engine introduced in '91 in the Lincoln Town Car '92 Crown Victoria and Grand Marquis 4.6L SOHC '93 Lincoln Mark VIII first to get 4.6L DOHC '94 Thunderbird 4.6L SOHC '96 Mustang GT and Cobra 4.6L SOHC and DOHC '97 Ford F150 and Expedition 4.6L SOHC '98 E-Series Vans 4.6L SOHC '99 6.8L SOHC V-10 introduced in new Super Duty trucks '00 Ford Excursion '02 Ford Explorer and Mercury Mountaineer 4.6L SOHC '03 Lincoln Aviator 4.6L DOHCBasic Modular Engine Facts
There are two Modular engine plants in North America - Romeo, Michigan, and Windsor, Ontario. Romeo is the old Ford Tractor plant. Windsor has been producing Ford engines since World War II. Although Romeo and Windsor Modular engines look the same on the surface, they are different inside. Here are the basic differences in Romeo and Windsor engines:
Romeo was the only Modular engine plant from '91-'95. Windsor came on line for '96 to build 4.6L and 5.4L SOHC engines for trucks and vans Although Romeo is primarily a car engine plant, it has produced Modular engines for trucks Although Windsor is primarily a truck engine plant, it produced Modular engines for '99-'00 Mustang GT Romeo engines employ different blocks, heads, and cranks than Windsor although they look similar Most Romeo blocks are marked with an "R" in the casting Windsor blocks are all marked with a "W" in the casting in two places Romeo heads employ bolt-on cam journal girdles Windsor heads don't have cam journal girdles, just individual journals Because Romeo and Windsor engines have different timing cover/cam cover bolt hole sizing, it is best to use Romeo heads and blocks together and Windsor heads and blocks together Romeo blocks have jackscrew cross-bolted main caps Windsor blocks have dowel pin cross-bolted main caps Romeo engines have primarily six-bolt flywheel/flexplate flanges Windsor engines have eight-bolt flywheel/flexplate flanges Oil filter/cooling neck types vary depending on vehicle type Timing cover depends on vehicle type Romeo cam sprockets are zero-fit and slip right on Windsor cam sprockets are pressed on Romeo cam covers have 11 bolts Windsor cam covers have 13 bolts Difference timing covers for SOHC and DOHC Same basic timing chain/sprocket system for both SOHC and DOHC DOHC engines have secondary timing chains for secondary camshafts SOHC has a standard oil pump and DOHC has high volume
There are four basic types...
There are four basic types of Modular crankshafts: nodular iron or steel, six-hole or eight-hole. Eight-hole is suggested if you're building for power. For street engines, you don't have to have a steel crank. Nodular iron is very strong.
These flat spots drive the...
These flat spots drive the oil pump on the front of the crankshaft.
Dished pistons are at the...
Dished pistons are at the heart of the Modular engine. Dish size depends on chamber size. PI (Power Improved) heads from '99-up have a small 42cc chamber and large dish. Non PI heads (before '99) have 52cc chambers and a smaller dish. Several piston dish sizes are available. Most Modular pistons are hypereutectic, not forged. Use forged pistons for supercharging and nitrous or when you intend the rev high.
This is a Windsor block, easily...
This is a Windsor block, easily identified by the "W" in two places along with dowel pin main caps.
An "R" and jackscrew main...
An "R" and jackscrew main caps identify Romeo blocks.
Bore spacing and sizing are...
Bore spacing and sizing are modest - 3.550-inch on all Modular engines. You can bore this engine .030-inch oversize. A maximum of .020-inch oversize is suggested. Cooling runs 60/40 -- 60 percent one size, 40 percent the other. We suggest a high-flow Cobra water pump for all Modular engines.
Here's a Romeo block marked...
Here's a Romeo block marked with an "R" but not all are marked this way. This is why the casting number and date code are important.
All Modular blocks have knock...
All Modular blocks have knock sensor bungs. Most SOHC blocks have one knock sensor provision.
Cobra blocks and SOHC service...
Cobra blocks and SOHC service blocks have two knock sensor provisions. Not all Modular engines will have a knock sensor.
The Modular engine is the...
The Modular engine is the most rugged V-8 Ford has produced since the 427. Cross-bolted main caps and skirted block construction ensure stability. Romeo blocks have jackscrew main caps. Windsor blocks have dowels you tap into place for main cap security. All are cross-bolted.
Because the Modular engine...
Because the Modular engine has extremely precise tolerances, don't make light of the machining process. Make sure your machine shop understands what this engine needs. Fasteners must be torqued per Ford specifications. Torque-to yield (also known as Torque Angle) must be followed to the letter.
Modular V-8s are cross-bolted...
Modular V-8s are cross-bolted two possible ways. Romeo blocks have internal jackscrews that are adjusted and torqued to support both main caps and block skirts. Then, external cross bolts secure the package. Windsor blocks have taper dowels that are tapped in place once main caps are torqued. Then external cross bolts are torqued.
Unlike older Ford V-8s, Modular...
Unlike older Ford V-8s, Modular engines have aluminum shell bearings. This is more than adequate for a street engine. Tri-metal bearings are necessary only with high-performance applications.
For all the hoopla and panic...
For all the hoopla and panic over powdered metal connecting rods, these rods are as strong, or stronger, than the forged rods in a 428 Cobra Jet. They can be reconditioned with new bolts and be as good as new. If you're going to supercharge or run nitrous, you need forged Manley connecting rods.
The standard SOHC oil pump...
The standard SOHC oil pump is an outstanding piece for street use. A weak spot is rotors that don't always stand up to stress. Billet rotors are an improvement. Melling offers an excellent high-volume oil pump. The Cobra high-volume pump is also a good idea. You will need to modify the SOHC's pick-up if you install these high-volume pumps.
The Modular engine's timing...
The Modular engine's timing system consists of two chains, two sprockets, two tensioners, two guides, two tensioner arms, and a crank sprocket. Modular engines from '91-'99 have steel chain guides. From '00-up they have plastic guides. Earlier engines have iron tensioners. Later engines have composite tensioners.
Never let the Modular engine...
Never let the Modular engine intimidate you.
Setting up timing chains and...
Setting up timing chains and sprockets is easy.
Just position marks and master...
Just position marks and master links together and you are timed.
Tensioners load the chains...
Tensioners load the chains via engine oil pressure to create tension.
Loading the timing set is...
Loading the timing set is easy once you know how. It all boils down to aligning all timing marks, just like a vintage overhead valve V-8.
SOHC heads all look basically...
SOHC heads all look basically the same with some differences. This is a Romeo head with cam journal girdles. It is also a '99-up Power Improved (PI) head.
This girdle design is what...
This girdle design is what makes the Romeo head different from the Windsor head. It gives cam journals stability. By the way, Modular camshafts do not have bearings. They ride on the machined casting.
Windsor heads do not have...
Windsor heads do not have cam journal girdles. Cam journals or towers stand alone. It has never been proven which is the better head -- Romeo or Windsor.
Romeo and Windsor heads have...
Romeo and Windsor heads have the same combustion chambers with identical port and valve sizing. This is the PI chamber, which is smaller than the non-PI.
Modular engines have high-tech...
Modular engines have high-tech valvetrains that weigh less and consume less energy because camshafts are composite, basically hollow tubes with lobes pressed on. Smaller valves and springs consume less energy and create less friction. Stamped roller rocker arms can withstand 10,000 rpm although we wouldn't recommend it. These are very durable rocker arms that make less friction.
The '99-up PI head has improved...
The '99-up PI head has improved port design and a better chamber. If you're going to spend money redoing a non-PI head, you should instead buy new PI heads from Ford Racing Performance Parts.
PowerHeads can build you a...
PowerHeads can build you a new CNC-ported set for what you'd spend on a valve job.
This is the '04-'09 3-Valve...
This is the '04-'09 3-Valve SOHC head with a unique chamber that has two intake valves and a larger exhaust valve for vastly improved airflow and more power. Believe or not, you can turn your 2V SOHC into a 3V SOHC with the right parts.