4.6 differences

[sg465]

Looking at doing a 4.6 swap into early mustang.already searched and what i can come up with is the 96-98 4.6 are weaker than the 99-02, correct? are all the same year 4.6s the same? what are the differences between the crown vic motors and GTs? what years came with forged cranks? thanks

 

[mogs01gt]

weaker?? They are all made with the same parts. Now the 99+ produce more power.

 

[bdcardinal]

the differences between the 96-98 and the 99+ motors are the heads and intake. the cams are also different. the 96-98 are referred to as the NPI(non power improved) while the 99+ are PI(power improved). there are no differences between crown vic motors and mustang gt motors. btw the police motors are also identical so theres no advantage there. none of the 2v motors have a forged crank from the factory. what year mustang is this going in. if you stick with a 2v motor then you should only have to notch the shock towers. if you go with the 4v motor then you will have to eliminate the shock towers.

 

[sg465]

differences

"weaker" does sound pretty dumb now. I was questioning internal durability. I want to put it in a 69 fastback. i know even the SOHCs are bigger in size than a 460. So if i find any SOHC motor the PI swap can come later? All aftermarket computer programmers list pretty much all 4.6s the same, so are computers the same in different cars? or does it matter cause they can all be manipulated? thanks for the help

 

[bdcardinal]

if you want to do it right i would definately consider getting forged internals (crank, conrods, pistons) just to give you that warm fuzzy feeling at night. i dont believe the sohc ones are bigger than a 460, however i think the dohc ones are. the main problem is the sheer width of the heads. if you ever see a bare block its really small, looks kinda like a 260 or a 289 to give you an idea of how small it is. the dohc heads are on the level of a boss429 head for size. it would almost be cooler to get a 99+ motor because you wouldnt have any spark plug wires cluttering up the engine bay(personal preference). also the DOHC motor looks better, and would give more power, although you can make some good numbers with a sohc motor. a cheap way to find a dohc motor would be to pull one out of a lincoln mrk8. the only differences between that and a cobra are the intake cams, and the intake manifold. they are generally cheaper because they are "lincoln" and not "cobra"

 

[sg465]

engine size

the ford catalog says the SOHCs are 28 inches wide and the 460 is 26. I got a 460 in my 88 stang and a 96 cobra so ill do some measuring. are the 99+ plug arrangement like you said "boss 429" style even on SOHC. what year of mark8s are DOHCs. is that the only other cars besides cobras?thanks a bunch

 

[bdcardinal]

well on the DOHC motors the plugs are in the center of the 4 valves like a hemi. on the sohc motors they are next to the fuel injectors. 99+ motors dont have spark plug wires. i think the mrk8s got the 4.6 in 1993. by boss 429 i was trying to say a similar size. the lincoln aviators have a 4.6 DOHC along with the 03+ mach 1s and marauders. after 99, the spark plug wires were eliminated in favor of individual coils on top of the plugs. the sohc motors have ones with an angled boot and a 7mm bolt that holds them down, while the dohc motors have a straight boot and no bolt holding them down. in my opinion, the dohc motor would look a lot meaner in your 69. especially if you took the valve covers off and painted them red or blue (there arent any aftermarket ones for the dohc motor except repainted stockers, or really expensive ones from sean hyland). o, if you get a chance pick up "building max performance 4.6 litre ford engines" by Sean Hyland. there is a ton of information in there about the differences with each year. i highly recommend that book.

 

[SteveZ]

All 93 to 98 Lincoln Mark VIII's are DOHC 4.6 engines. The earlier ones are marginally stronger than the later ones due to emissions calibrations and other factors. They are also a good source to find a DOHC block with a 4R70W AOD-E attached ala Mach1.