I have a 1997 Expedition with 207,000 miles on it. No, this is not a misprint. It has a 4.6 and is 2WD.

The engine is still running OK, although it has loss power throughout the years. I was thinking about rebuilding it or maybe swapping it out for a 5.4 Lightning. The only problem with swapping it is that it will probably cost me between $10-15K to do it right.

What can I do to my 4.6 and get about 300hp out of it? I want to stay below $10K including replacing the tranny.

I am going to be rebuilding the engine so any suggestions on pistons, head work, intake, etc, would be great. I know that in order to get 300hp, I will need a supercharger so any suggestions on that would be great too.

Thanks.

 

get the 'L'...spend your cash wisely

 

I understand where you are coming from with your expedition with over 200k on it, you will get next to nothing for trade in. On your mods, it wont be hard to get over 300 hp out of a 4.6. I am not a load of info about specific products but build you bottom end fairly strong. Nothing drastic will be needed, you dont need to spend a fortune on rods and pistons. Just quality parts. Dont even bother with the heads have them checked and if they are ok. Just put them back on there stock. You will still fall in the 7-8k here so that will leave you with 2 grand at the least for the tranny. That is still plenty for a great 4r70w. I am surprised you haven't gotten more replies here. I know that there are people here on the forums that know the specific parts you need. Maybe they will speak up soon. One word of advise here. Don't get in a hurry on this rebuild. Since you still got a running engine scope all your prospects out on builders and such. You didn't mention if you were rebuilding this yourself or not . If you are doing it, you can go hog wild on engine parts. Since your labor will be free.

 

You have several options. First off the power you want will eventually cause trans and rear end failures due to the mileage.
I priced out a tranny yesterday from Ford. My cost is $1300.00. A rear end rebuild is around $800.00.(I know some of you can do this for less).

Like above said, $2K for this work. Labor ofcourse is extra.

Now then. An L engine is not that expensive over at www.KarKraft.com What you have to wonder about is smog rules. Computer and wiring. These I have no clue about.

There is a dealer in SoCal installing blowers on new trucks/expeditions with the factory 4.6.

My suggestion is to get a crate engine. Karkraft or dealer will be glad to help you here.(36K warranty) And then put the pump on it.

Regarding the heads if you decide to overhaul. With 200K you should at least have them machined(valve job). One thing that is a problem with the mod heads though is that there apparently is not a whole lot of material to machine and stay within the tollerances. Then you are getting new heads. Which goes back to the crate engine.

If you do rebuild try and get a forged short block and or talk to the engine shop/sales company's in the stang mags. They seem to have many short and long blocks advertised in these types of magazines.

Good luck,

Mike

 

I was looking into getting more power out of my 4.6 and came across this supercharger-Pro Charger. They will put you well above 300HP and run you less than 4K. You will have plenty of $$ for tranny and rear end if that it a problem. Pro charger says that you will get over 300HP without anything other than a stock engine and besides that it is removeable and in Cali smog legal and they really don't reduce fuel economy that much unless you stomp on it a lot.