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Discussion Starter #1
I want to beef up the power on my '96 Dakota Sport, but I don't want to use headers. It's the 318 magnum and I was wondering what manifolds provide the best performance and will fit in my Dakota. It's 4x4 so it has a front axle.
 

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The 92-93 exhaust manifolds on the Magnum engines were said to flow better than later years. I know that I can pull a car behind my 3.9L V-6 4WD Dakota with no problem.
 
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The exhaust manifolds aren't an issue with breathing, it is all in the heads themselves, requiring a good porting of them along with a little work inside the starting points of the intake runners themselves to get more power. Opening up the exhaust isn't necessary given you won't hit the rpm ranges a set of headers work best, and the electronics/smog package requres the engines to maintain a certain amount of back pressure in order to run clean, which can be an issue in many places these days. With these things in mind, too, a mandrel exhaust pipe instead of a crimp bent pipe will help on that side, and it is a lot cheaper and easier to reinstall than headers. Back to the heads, where the initial breathing and power making starts, although you have 1.92 intake valves, which are large enough for a street 318/5.2 4X4, the ports themselves have enough restrictions in them that not nearly enough of the port volume is utilized, and if the 5.2 heads are the same as the 3.9, there is a shark fin that reduces flow even more. I ported my heads, removed the shark fin in the intake runner, and removed the sharp edges in my combustion chamber and my 3.9 is pretty stout down low and on top where it used to lag a bit, everything else is totally California stock and smogs in low single digits to boot.
 
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The 1999 Dakota R/T I owned before (the one that got crunched) had headers, really nice Gibson headers the previous owner spent a lot of money on. When the headers required removal for the front end suspension rebuild I did on the truck, I put stock manifolds back on it and noticed no change in performance or MPGs.
 

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Discussion Starter #5
valiant67 said:
The 1999 Dakota R/T I owned before (the one that got crunched) had headers, really nice Gibson headers the previous owner spent a lot of money on. When the headers required removal for the front end suspension rebuild I did on the truck, I put stock manifolds back on it and noticed no change in performance or MPGs.
the '99 Dakota R/T was a 360 which had bigger ports. I could easily do a motor swap but I want to keep it as stock as possible. That is the point of putting manifolds. The most radical thing I would probably do is put a cat-back exhaust.
The main problem I am worried about with headers is that it's an EFI with lots of electrical parts, and knowing that Dakotas (though not mine, thank Allah!) tend to have electrical problems, I worry about to much heat damaging my ECM, Wires, and what not.
Now my Volaré coupe... that's a different story :thumbsup:
 

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the '99 Dakota R/T was a 360 which had bigger ports.
The manifolds (and the heads) were the same between the 318 and 360 Magnums. Even the R/T motor was just a standard 5.9L Magnum motor with a little better exhaust after the manifolds.
 

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What's your complaint about headers?

I ask because headers that are ceramic-coated inside and out are awesome! Almost no heat in the engine bay, and they sound nice!
 

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I don't like them because the heat, but also because the question isn't if they leak or not, but when they will start.
 

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Well, personally I've never had headers leak. I have TTIs for my Cordoba (chrome, bought unused second-hand, will probably replace with ceramic) and I previously had Doug Thorleys that I bought NOS and had ceramic-coated inside and out, and gave those to a friend with another Cordoba and he hasn't had any problems with them. Only reason I parted with the Thorleys is that they would only clear a 904 transmission and starter position, not a 727, so when I upgraded to the bigger transmission I couldn't use 'em anymore.

I have had a friend that's had problems with Hedman, he literally ripped one apart at the collector and lost that side of the exhaust. He's the first one I knew who switched to TTI, and his car prototyped C-body wagon headers and full exhaust. So far he hasn't had any problems with the setup in the many years he's had it.
 

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I had Gibson headers on my last 99 Dakota R/T. They didn't leak and won't leak as they were every bit as substantial as the factory manifolds. And the previous owner paid a pretty penny for them. But they were designed so they had to be removed when I did the front end work on the truck and I got rid of them then.
 

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huh.. I'm gonna have to check them out. I just technology has changed a lot since the 80's, before it was just a common occurrence for headers to leak, and so people just lived with it. Guess I'm gonna have to delve a little deeper into the TTI steel and Powder Coated Headers. Hell if they both seem to prevent it (along with the heat) might look into getting powered coated TTI headers. Thanks for teaching me something new. That is what I like about Allpar more than any other forum. You guys know exactly what I need to hear. :thumbsup:
 

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*grin*

If it's any consolation, that friend that got me started with TTI's products had a pile of old headers in his junkyard side of his backyard. Looked like he had ten pairs there. I wouldn't be surprised if a lot of people had the kinds of problems that you describe.
 
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