2v 5.4

wmburns said:

For the average joe, installing a 5.4 is a LOT of work. Sure it can be done. I have read several post regarding it. I also think it is telling that the cars are SOLD after doing sooo much work.

If it was up to me, I spend the $$'s on a name brand super charger kit. It will bolt up and will work as advertised.

If you had $$'s to burn, I suspect the breathing problem could be solved by a supercharger. But then way not build a stroker 4.6? If that is not enough, add a supercharger. Again, not tons of custom work with the possibility of a less than desireable outcome.

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Gearbanger 101 said:

As far as I know, all of the factory PI heads use the same cam profiles. What hurts you is when you try to make 330ci breath through the same intake as that was originally designed for 281ci. The 4.6L car engine has a long runner, small diameter intake that is made to promote torque in the lower and mid regions to make of for the loss recognized with its small displacement. Going with addapter plates adds another inch to the already long runner length, which increases the problem. Plenty of torque down low, with no gain in horsepower.

Also, the 5.4L still sufferes from the small bore and makes up for its displacement with a longer stroke. Great for torque, but really isn't going to do anything to promote deep breathing at high RPM. Unless you're running some form of forced induction on the 5.4L engine, you're not going to see any substantial gain in usable horsepower.

But...when you do add forced inductions, you're rewarded with plenty of both. The Roushcharger kit for my 5.4L 3V engine promotes 445hp and 500lbs/ft with only 5-6psi....and that's one of the more conservative Positive Displacement kits on the market. That's unheard of power levels for a 4.6L....it doesn't matter how many valves its sporting.

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Gearbanger 101 said:

I guess it all depends on your definition of fun. If burning tires and sliding the rear end around is your thing, then yes....I'd say a 5.4L under the hood would be a lot of fun.

If getting walked by bolt on 4.6L cars after the first 500ft and adding unnecessary weight to the nose of your vehicle (negatively affecting braking and handling) isn't your bag, then I would probably advise against it.

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