my truck is a 2004 f-150 ext cab 4x4 with the 4.6....i am thinking about putting a big block in it. i was just wanting to know how hard you think this swap would be and what major mods will need to be done??? this truck will also have an 8 inch BDS lift running 37x13.5x20 tires...just looking for a little advise and tech help.... thanks, kenny

 

You'll need a carb, or a whole stand alone EFI

all new tranny, driveshafts, motor/tranny mounts



You are going to lose all of the electronics in the interior. The PCM and Inst. cluster control almost everything...gonna be a PITA IMO to keep them functional, but not in the loop for Motor/Tranny operations



Just a few things off the top of my head. Good luck...and please stop back by if you pull it off. Can't see why you'd want a big-block personnally. You might gain a bit torque, but the 5.4 is pretty decent. Especially compared to a stock 460....now a built 460

 

the motor should be close to 750hp according to the engine builder....main concerns were the motor mounts and if i will need custom made headers....

 

yes and yes

have you considered that the frame itself won't be strong enough for that kind of power


a Big block weighs alot...up to 1,000 lbs on occasion. add to that some violent high HP ratings...and stuff gets bent.


another problem you might run into will be the physical clearance for the those headers. the 5.4 3v is a pretty wide motor...but a 460 is most likely wider...might have to run the exhaust outside the frame rail.



it's really one of those things you have to find out once you test fit

 

instead of a 460....why not a 6.8?


some folks already put a V-10 in a 2000 model F150.

 

why not just build the 4.6 and put forced induction. You should be able to get plenty of power out of say a kenny bell 2.2 or even a 2.8 if you were looking for big power. Then you dont have to worry about motor fitment or loosing your pcm. Just upgrade your internals, slap on the charger and get it tuned. Should easily be able to make in the 600 range safely and then you could probably get a tune for higher horsepower applications.

You could also always go turbo. I know HP makes a twin kit for the mustang. I have also seen one on an Expy i think by the same company and it made 550.

Just some ideas and will save you some time and headaches

 

If you really want to swap in a big block....expect to have to hand build motor mounts, exhaust, and crossmembers....

You'll also need a new tranny and transfercase if its 4wd...your 8.8 axle isn't going to hold up to 700 hp so you'll need to swap in a bigger rear axle...new fuel lines and an upgraded pump for that hp...

 

Frankly unless you are independently wealthy, this is a project that I would stay waaaay far away from. As mentioned, you can get comparable power out of a forced induction modular motor.. that will actually semi "bolt in". There is much more with the driveline to address as well.

 

Yea i was just giving you options for the power.

With the setup you plan on running you will need stronger axles, not necessarily haev to change the rear end but you will def have to reinforce it. Upgrade the trans and transfer case. There are plenty things you must do to keep this thing as reliable as possible. I would expect to pay about 35-40k to fabricate the parts you need to swap everything and beef up everything for the 460. Labor will be your biggest cost here unless you have all the machinery to complete something of this magnitude.

Where as you may only spend 15-20k for the supercharger or turbo setup plus all the beefing.

just my $.02

 

first of all thanks for all the input,,,i guess the main reason for wanting to do this swap is that i really have not seen any out there.....i definetly see the ups and downs with this kind of project, but i have a good friend of mine doing all the engine work plus i already have the big block and if needed i do run a FORD store here in Biloxi,MS...so there are 6 master certified techs if i need them.....if anyone out there knows of any big block swap in a late model truck please let me know.....thanks again for all your help,,,Kenny

 

if you can get cheap labor id say go for it. If it works out you can sell it as a kit and get your money back for the R&D. Like the monster miata kits and all. Im sure plenty people would be interested if you could make the kit affordable.

 

still hoping to be able to talk to someone who has done something like this.....i really want to do this project.... i just hope it doesnt turn into a nightmare....lol.....we shall see