The following information is supplied by Kar Kraft Engineering, Inc. for the automotive enthusiast and hobbyist using Ford V8 modular engine components.

This information is supplied to the best of our knowledge as a courtesy to our website visiting customers and is not to be used for commercial or advertising purposes.

Kar Kraft Engineering, Inc. does not represent itself as Ford Motor Company or as any entity or subsidiary of Ford.

click on picture to enlarge

4.6  2valve cylinder heads P.I. head pictured

1991-1999 version used small intake ports

1999-2000 Mustang GT engines built in Windsor used the newly designed P.I. head which stood for "Power Improved"

2001-2006 version on all vehicles built with the 4.6  2valve are P.I. heads with casting number beginning with 1L2E on the head. left and right heads are interchangeable.

* wildcard: P.I. heads built at the Windsor engine plant have machined cam caps

4.6  3valve cylinder heads 

also used in 2004-present F-series with 5.4 engine

used in all 2005-2008 Mustang GT with 4.6 all aluminum engines.

4.6 and 5.4  engines with 3valve heads use variable cam timing (VCT)

4.6 and 5.4  3valve cylinder heads are identical

FYI- wanna get rid of the VCT on the 3valve heads? install the cam gears from a V10 3valve engine. V10's do not have VCT

4.6  4valve cylinder heads (1993-1996)

introduced in 1993 on the Lincoln Mark Vlll and continued thru 1997

same basic head as used on the 1996-1998 Cobra  (cam differences)

the 1996/98 Cobra intake manifold will fit the Mark Vlll engine

heads are dual runner intake design with controlled secondary runners

4.6  4valve cylinder heads (1999-2004)

a new single intake runner design introduced in 1999 on the Cobra

new design head also used on the 2001 Cobra

another improved version introduced on the 2003/04 S/C Cobra. still a single intake runner design with improved intake and exhaust flow. same basic head was also used on the 2003/04 Mach1, 2003/2005 Marauder and 2003/2006 Aviator. All had 2C5E casting numbers on the heads.

intake manifold configuration from 1999-2005 will all interchange on the 2C5E cylinder heads however will not interchange with earlier 4valve heads from 1993-1998. the earlier 1993-1998 head uses a dual runner design while the later 1999-2005 heads use a single runner design

*Wild Card:

2valve head engines,  3valve head engines,  and 4valve head engines are never interchangeable as far as intake manifolds. while the basic displacement of the engine may all be the same (4.6), the cylinder head designs are all unique to the valve version of that engine series. in other words, a 2valve intake will not fit 3valve cylinder heads, a 3valve intake will not fit 4valve cylinder heads and so on.

4.6 & 5.4   4valve cylinder heads (2000-2008) special SVT

one more monkey wrench gets thrown into the mix!

in 2000, Ford manufactured the limited version of the Mustang Cobra called the Cobra "R". this was a very limited version of the Cobra. not all Cobras are Cobra "R"'s! These cars were built with a high output version of the 5.4 Navigator engine using unique high flow 4valve cylinder heads called the "R" heads. while yes they will bolt on to any 4.6 or 5.4 engine, the intake ports were redesigned which calls for a unique intake manifold.

in 2004, Ford manufactured the Ford GT supercar which used a very similar version of the 2000 Cobra "R" cylinder head. there again a unique intake manifold to fit these heads was also designed and used with a supercharger on the 5.4 4valve engine and has a unique bolt pattern on the exhaust side.

again in 2007, Ford manufactured the SVT  GT500 engine which also uses the Ford GT/Cobra R cylinder head along with a unique intake manifold.

the Cobra R, Ford GT and 5.4 SVT GT500 engine intake manifolds will all interchange with each other with minor fitment alterations.

*Wild Card:

the 1999/01 Cobra intake manifold and 2003/05 Mach1, Marauder and Aviator intake manifolds will not fit the 2000 Cobra R, Ford GT or SVT GT500 heads even though they are all 4valve heads. just as they will not fit the 1993-1998 Mark Vlll or Cobra heads.

also, exhaust ports and bolt spacing is unique to the "R" head, Ford GT and GT500 head. exhaust manifolds from a 2001 Cobra will not bolt onto these heads.

Blocks:

the 4.6 aluminum blocks manufactured from 1993-1998 and some 1999's were manufactured in Italy by Teksid. these were a very expensive block for Ford to have made and are probably one of the most durable blocks produced for the 4.6. these blocks are very desirable among racers. these blocks can be used for any 4.6 engine build with any of the 2valve, 3valve or 4valve heads including Cobra R heads.

the strongest Teksid block produced of that vintage was the front wheel drive block in the 4.6 Lincoln Continental due it's added ribbing in the sides for it's East/West fitment in the FWD Continental. motor mounts become difficult with that block but the added strength makes up for it! Also, a starter pocket has to be fabricated to use these blocks since they have no starter pocket, similar to the Ford GT 5.4 aluminum block.

Most of the 4.6 aluminum and cast iron blocks can all be interchanged for whatever application is needed. special attention needs to be given to Windsor iron blocks which have a big "W" cast in the block. while some say it's a stronger block, some problems can occur when installing the timing cover. it's possible not all bolts will line up on the Windsor blocks. (usually not a huge problem)

The newer aluminum blocks can be used in an earlier applications by simply drilling out and re-tapping the knock sensor holes in the valley from 5/16" out to 3/8". basically a newer 2003 block can be used in a 1996 Cobra since the early Teksid blocks are harder to find. in fact, Ford discontinued the service short block for the 1996-98 Cobras due to the expense of the Teksid Italian block. the 1999/01 Cobra short block can be used as a replacement by drilling out the knock sensor holes as described above.

5.4 Ford GT aluminum blocks are one of the strongest alloy blocks ever produced by Ford. the production block is set up for dry sump oiling and has no starter pocket provision since the starter is located in the transaxle. However, these blocks can be machined to be used as a standard wet sump application and the starter pocket can also be used for a standard starter.

5.4 S/C SVT 2007/08 iron blocks are the same as a standard 2002 and up F150 and Navigator block except for one thing which is the water pocket from the front of the engine over to the oil/water adaptor on the driver's side of the block is not machined thru. the 2007/08 S/C SVT engine uses a front outlet water pump which means water does not circulate to the side of the block.

Crankshafts:

while the early 1993-98 Mark Vlll engines look very similar to the 1996/98 Cobra and the Intake manifolds can be interchanged, the main difference between the 2 engines is the crankshaft. The Mark Vlll uses a cast iron 6 bolt fly wheel version crankshaft while the Cobra uses a machined steel 8 bolt flywheel high performance crank.

Also, the newer 2003/04 Marauder, Aviator and Mach1 automatic transmission engines also use a cast iron crankshaft except for the manual transmission Mach1's which use a Cobra crank. The 2003/04 S/C Cobra also use a steel high performance crankshaft. All 4.6 rod journals and mains maintain the same diameters.

Flywheels and Harmonic Balancers

While there are differences in applications from engine to engine, all balancers and flywheels are balanced to "ZERO" on all modular engines. rotating balance on these engines is all done internally.

Valve Covers

 We're not even going to begin to talk about 2valve plastic valve covers. 11 bolt, 13 bolt, RH oil fill, LH oil fill. We're not going there!

 However, we will talk about 2007/08 SVT 5.4 S/C engine valve covers. A 4V valve cover is a 4V valve cover right?  WRONG!  The 2007/08 5.4 SVT engine began with a fitment problem in the 2005/08 Mustang chassis. The partial fix was reduce the size of the valve cover hump for the front cam gears to clear the shock towers. The result was smaller cam gears and smaller humps in the valve covers which means the 07/08 SVT valve covers cannot be installed on a production Cobra or 4valve engine with the standard front cam gears. Trust us, it immediately creates your own milling machine inside the valve covers on the cam gears!

3valve valve covers- is it even possible to manufacture an uglier valve cover????? a beautiful Mustang GT or F150 and this is the valve covers you get?

come on Henry! you can do better than that!

Speaking of the 3V valve covers, in 2008, the Mustang GT and we believe the F-series valve covers now use a revised attachment system by reducing the number of valve cover bolts to attach them to the heads. the heads retain the same amount of threaded holes for the valve covers but the new covers skip every other hole for attachment. the 2005 thru 2008 valve covers will interchange with each other regardless of the vintage of cylinder head.

5.0 valve covers- the 1994/95 Mustang Cobra used a unique set of tin valve covers. the one noticeable thing is that these came with "COBRA" lettering on the valve covers. the second thing is that they are very heavy compared to stock 5.0 GT valve covers. the reason is a double layer of metal with a sound deadening epoxy  between the layers to quiet down the rattling of the roller rockers which are production stock on a 5.0 Cobra. NOTE: while 94/95 Cobras use these valve covers, the very rare 1995 Cobra R uses the same valve covers but are modified to clear the intake inlet since these cars have a 5.8 engine instead of a 5.0.

Want to use an original pair of pretty blue 2005/06 Ford GT valve covers on your DOHC engine? yes, they will fit and bolt up but make sure you have another way to add oil to your engine! the Ford GT uses a dry sump oiling system with an oil reservoir tank which is where the oil gets added. these valve covers have no oil fill provision or oil cap!

6.2 litre engine

A lot of speculation has been written on the new 6.2 litre V8 engine. Well here are some facts and here is also some more speculation! If you think the 4.6 and 5.4 DOHC engines are wide, you haven't seen a 6.2! It's huge! Several versions have been test run in the dyno room and for durability with both plastic and aluminum intake manifolds. We're guessing the production version will be a plastic manifold if we've seen the latest version. The block is cast iron, with dual spark plug aluminum heads which are like nothing you've ever seen before! The valve covers are also cast aluminum with "Power by Ford" casted right in the top which looks great! Oh and did we mention that the block has "The Boss is Back" casted in the valley of the block? While we know this engine was designed for use in the heavy trucks to replace the V10, what else is the thinking behind the use of this engine? Unless the shock towers get revised in the 2009 stang, they're ain't no way this thing will fit in the current configuration engine bay. The cool thing about this engine and having a cast iron block is that a local Nascar owner who owns a company here in Livonia (do we really need to mention names?) has punched this engine out to 7 litres which has been drag raced this year already and did outstanding. 7 litres=427 cubic inch. Do we hear a marketing strategy taking place with this engine? Hopefully!

More to come!