Last post on Jun 30, 2011 at 1:07 PM
You are in the Ford Crown Victoria/Mercury Grand Marquis
What is this discussion about?
Ford Crown Victoria, Mercury Grand Marquis, Engine, Sedan
#1 of 3 Swapping a 4.6 for 5.4 in a Grand Marquis?
Nov 29, 2008 (3:10 pm)
Does anyone know or heard of hard it would be to swap out the 4.6 for the 5.4? I've seen people who've done it in magazines and such but I was wondering if takes alot of fabrication for the motor mounts and such.
#2 of 3 Re: Swapping a 4.6 for 5.4 in a Grand Marquis? [Mercman76]
Jun 30, 2011 (8:54 am)
A 5.4 should bolt in right in place of the 4.6. However, it will be a little wider, and a little taller, so you may have to cut the Y-pipe in the exhaust to get it around the 5.4 block. Also, the intake manifold on a 5.4 is a lot taller than the 4.6 manifold, and your hood won't close. There are low profile aftermarket aluminum manifolds for the 5.4, but for the life of me I can't remember who makes them.
The 5.4 really doesn't make that much more horsepower than a 4.6. What it does have is a lot more low-end torque. If this is what you want, a 5.4 will fit the bill perfectly. If you're looking for more of a higher revving, high horsepower engine, a Marauder or Mk VIII 4.6 DOHC engine will probably be more your cup of tea.
#3 of 3 When swapping engines
Jun 30, 2011 (1:07 pm)
Does it matter to the onboard master computer. IOW is the old computer compatable with the new engine?