6.4L upgades

[theviking]

Nope, was referring to their LT headers. I'm saying you are going to have to build a custom Y pipe for the SRT shorties so why bother going through all the trouble. Unless you really hate the idea of aftermarket cats then anything ARH builds will be well worth the money. I have about 60k on mine and they have never given me an issue. Just my 2c.

 

[Albert525]

long tubes modify cats, and that's not street legal, that's why I want sorties. Probably too much work for 10 hp because its a re design, but honestly wouldn't we want 420?

 

[theviking]

I dropped a second 0-60 with my long tube headers and it still passed NJ emissions. So in my mind it was well work the cost and risk. Between the HF tune, ARH headers and cat back (along with some other more minor mods) I was able to run a 6.08 0-60. Point is there are proven mods if you're after HP gains. And so far nothing I've done has hurt reliability other then needing a tack weld on my cat-back to keep it from rotating.

 

[pacofortacos]

Cast manifolds are for towing, headers and long distance towing do not really work that well.
Headers just generate way to much underhood heat when towing a decent load at highway speeds.

Wrapping the headers helps a little with the heat, but you still get much more heat than the cast manifold w/heat shields. Ceramic coating doesn't do enough either.

What would be nice would be a nice set of cooled headers or somehow highly insulated.

 

[theviking]

Well all the ARH stuff is 304 stainless so I believe that helps considerably with the radiated heat.

 

[Albert525]

Cast manifolds are for towing, headers and long distance towing do not really work that well.
Headers just generate way to much underhood heat when towing a decent load at highway speeds.

Wrapping the headers helps a little with the heat, but you still get much more heat than the cast manifold w/heat shields. Ceramic coating doesn't do enough either.

What would be nice would be a nice set of cooled headers or somehow highly insulated.

Thats interesting, no idea cast would hold in heat better.

 

[pacofortacos]

I had stainless ceramic coated JBA shorties on my 5.9 dakota, when I towed the boat from PA to FL, I actually melted a few plastic pieces under the hood.
Next trip, I wrapped the headers (probably about 50%) and it stopped the melting but there was still a tremendous amount of heat when I opened the hood to check on everything part way down.

Took the headers off and went back the stock manifolds - missing most of the heat shields - and it was significantly cooler under hood.

The headers cooled off quicker than the manifolds when the engine was shut off.

Generally the manifolds are quieter also - but I think the newer hemi manifolds are not as thick as the 5.9 magnum manifolds.

 

[Albert525]

I had stainless ceramic coated JBA shorties on my 5.9 dakota, when I towed the boat from PA to FL, I actually melted a few plastic pieces under the hood.
Next trip, I wrapped the headers (probably about 50%) and it stopped the melting but there was still a tremendous amount of heat when I opened the hood to check on everything part way down.

Took the headers off and went back the stock manifolds - missing most of the heat shields - and it was significantly cooler under hood.

The headers cooled off quicker than the manifolds when the engine was shut off.

Generally the manifolds are quieter also - but I think the newer hemi manifolds are not as thick as the 5.9 magnum manifolds.

honestly this is the first I have read this.
I appreciate you guys sharing.
Very good to know.
MAkes sense why they would do cast vs lots of engineering with coating, wrap, heat shields then just 10hp

 

[pacofortacos]

Noise also plays an important part, the factory spends big $$ on NHV reductions and let's be honest. Headers aren't as quiet as cast manifolds.

 

[theviking]

With the stock cat-back I could hardly hear any difference between the the factory setup and headers. With full length catted ARH headers/MF cat-back it actually drones LESS then it does with just a cat-back and the stock manifolds/y-pipe. Go figure.

Full length headers are going to give way more then 10 hp on average. According to ARH it's more like 25hp and 30ft/lbs. I personally never had an issue with excessive heat but there is a lot of airflow under the hood and underneath these trucks.

If you're going to worry about every possible issue then I agree, just leave it alone. Nothing is ever quite as reliable as stock. But that's always the trade-off.

 

[Albert525]

I prefer street legal