blksn8k
Well-Known Member
I have been thinking about what I would do with my ST if I decided to keep it indefinitely. One of the issues I have is that even with the 4.6L V8 I would really like to have a bit more power for towing.
I know there are supercharger setups available but I would not feel safe doing that to a stock engine, especially one with relatively high mileage.
There is also the possible option of replacing the 4.6L with either a 5.4L 3V or even a 5.0L Coyote. Neither of those would be a direct bolt-in. The 5.4L is probably too wide and would present exhaust routing issues and potential problems with engine accessories and hood clearance.
The Coyote would probably be even more difficult just due to all the electronic issues. It would require a different computer just to control the TiVCT and then how do you deal with the transmission programming, instrument panel, etc., etc. ? I know that one has been done but the end result was a two-wheel drive truck with a manual transmission. My truck is a 4x4 and I intend to keep it that way.
There is now another potential option that just might combine the best of all worlds.
Ford Racing now has a 5.3L shortblock assembly that is based on the 4.6L modular block. It includes a cast iron block, forged pistons, rods and crankshaft and 4-bolt mains and would yield a 10.5:1 compression ratio with 3V heads. It uses a 3.701" bore and 3.750" stroke resulting in 5.3L (323 cu in) compared to the stock 4.6L (281 cu in).
JDM Engineering has a kit that includes the above shortblock and the parts required to install your 3V heads. Although this would be more expensive than a remanufactured 5.4 you would be gaining almost the same displacement along with the possibility of adding a supercharger later without having to worry about the engine being able to handle boost.
It would also have the same physical dimensions as the original 4.6L which would eliminate any fitment issues associated with the taller deck height of a 5.4L block and all of the engine accessories and electronics would be a direct bolt-on. It would also bolt up to the existing transmission and exhaust system. It should also weigh about the same as the original 4.6L so there should be no ride or handling issues that might be encountered with the larger 5.4L.
Other than price, what am I missing?
I know there are supercharger setups available but I would not feel safe doing that to a stock engine, especially one with relatively high mileage.
There is also the possible option of replacing the 4.6L with either a 5.4L 3V or even a 5.0L Coyote. Neither of those would be a direct bolt-in. The 5.4L is probably too wide and would present exhaust routing issues and potential problems with engine accessories and hood clearance.
The Coyote would probably be even more difficult just due to all the electronic issues. It would require a different computer just to control the TiVCT and then how do you deal with the transmission programming, instrument panel, etc., etc. ? I know that one has been done but the end result was a two-wheel drive truck with a manual transmission. My truck is a 4x4 and I intend to keep it that way.
There is now another potential option that just might combine the best of all worlds.
Ford Racing now has a 5.3L shortblock assembly that is based on the 4.6L modular block. It includes a cast iron block, forged pistons, rods and crankshaft and 4-bolt mains and would yield a 10.5:1 compression ratio with 3V heads. It uses a 3.701" bore and 3.750" stroke resulting in 5.3L (323 cu in) compared to the stock 4.6L (281 cu in).
JDM Engineering has a kit that includes the above shortblock and the parts required to install your 3V heads. Although this would be more expensive than a remanufactured 5.4 you would be gaining almost the same displacement along with the possibility of adding a supercharger later without having to worry about the engine being able to handle boost.
It would also have the same physical dimensions as the original 4.6L which would eliminate any fitment issues associated with the taller deck height of a 5.4L block and all of the engine accessories and electronics would be a direct bolt-on. It would also bolt up to the existing transmission and exhaust system. It should also weigh about the same as the original 4.6L so there should be no ride or handling issues that might be encountered with the larger 5.4L.
Other than price, what am I missing?
Last edited by a moderator: