H.O. cams are available at www.moparpartsamerica.com for under ~175 each. When I researched it back then it looks like a no brainer swap giving 15-20 hp gains with slightly higher torque, no other tuning needed. Your intake should be OK, I think all '03 models were the newer style.

My Durango is a daily driver with high mileage (165k+) so I didn't think it was wise to increase the HP any without doing a full rebuild. I'm looking locally for a (cheap!) 4.7 to rebuild and drop in someday, so I may investigate doing this again. The Dakota forum has some good threads on 4.7 mods as well.

No reason to avoid rebuilt heads as long as they're reputable. Locally NAPA quoted me a good price but would have nailed me on the core as mine was cracked. Make sure others don't do the same. (get it in writing!!!)

Bob

 

Update

I'm going to skip the HO cams, I've got 140k+ miles on this thing already.

I've gotten my good head back from the machine shop, it was in great shape. Also got the replacement head in as well as all the gaskets a guy could want, and a timing kit I found cheap (everything but the gears/sprokets)

There are a couple things I am still looking for,
where can I get a 180degree thermostat? Autozone says nothing is available other than OE.

There is a torx bolt that attaches the timing guide/arm/whatever to the head, any ideas where I can get one? the one in my old head sheared off. . .

How bad is the oil pan to remove? I am missing one of the cap bolts that broke when the camshaft broke. All my oil passages etc are clear, so it must have fallen down into the oil pan. I'm guessing it's pretty important to find it I know I have to pull the front axles, is it as much of a pain as it sounds?
Lombard

 

no 180* stat for the 4.7, you want to stick with the stocker designed stat because of the weep hole anyway, the 180 stat is a recommended upgrade on the old 5.x series engines, not for the newer 4.7, for the bolt i would say almost any auto store should be able to get you one if not try taking whats left to a hardware store to find one thats the same thread and size

 

Like Sharps said, the torx bolt should be relatively easy to match something similar at a hardware store. I'm sure a dealer could get it for you also.

Oil pan sucks to remove..... actually the oil pan is easy, it's all of the stuff you have to take off to GET to it sucks! If you can avoid it I would. See if you can snake a flex magnet into the pan openings under the timing cover first, it'll save you a TON of work.

If you do end up pulling the pan make sure you check / clean / replace the oil pump & pickup tube assembly as required. Personally I'd sepnd a lot of time fishing with a magnet first.

I once found 3 pennies when I pulled an oil pan on a motor. Would love to know the story on how THEY got there!

Bob

 

its too bad you dont know the story, i woud love to hear it

 

+1 Go to the dealer and buy a OEM T-stat, don't go aftermarket.

Your cap bolt could be stuck in an oil passage so look really close for it. I would but some compressed air into each of the return holes in the head to ensure they are flowing.

 

Ill be honest with you trying to rebuild those 4.7L are more trouble than they are worth. I spent $2800 rebuilding mine with all performance parts just to find out the block to head surface was warped. i bought a brand new 4.7L from powersource for $2400 and it came with a 5 year unlimited mileage warranty.

 

in your case that may be true, but that is not what most people will experience.

 

Not necessarily a fair statement here. Before doing a rebuild on *any* motor you need to make sure that it's worth rebuilding. In your case if the deck was warped to begin with then the motor was most likely heated up pretty good multiple times before the rebuild, making it a questionable candidate from the start. Also, adding "performance" options to some motors won't give you the same "horsepower - to - dollar" ratio than others just based on popularity. A prime example here is a Chevy small block. (sorry, I know that's a bad word in here!) Performance parts for them are a dime a dozen, driving the market price way down. The 4.7 doesn't have the same consumer market, so naturally things like special grind cams, flowed heads, etc. are going to be substantially more.

Just my opinion of course!

Bob

 

Hate to bring this thread back from the dead, but I have to. First of all thanks for all the input, after coming up with the money I needed I got everything back together.

Bad news is, that it cranks, but won't fire. It turns over, I have fuel pressure in the rail, but don't know if the injectors are firing, and don't know if I'm getting spark. This durango is the first vehicle I've owned that has the coil on plug, can I just pull one of the coils, put the plug in it and see if it sparks?

recap of the project so no one has to reread the thread

broken camshaft on passengers side, head had to be replaced.
all timing guides etc were worn out - installed timing kit while I was in there.
new head on passengers side
machined/valve job on drivers side head

everything is back together, I turn the key, I hear the fuel pump, it cranks, but never fires.

where do I start?


thanks.