Hemi Exhaust Manifold New Design?

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EdGs

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@Sherman Bird, is your '02 4.7 a JTEC or NGC motor?
I have an earlier '02 with a JTEC in it.
 

EdGs

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When I did the head gaskets on mine, I had to check because the timing chain set listed 2 different ones, with different reluctor wheels on the camshaft.

There was a difference in the plugs on the ecm as well, 3 or 4 plugs IIRC.

If any engines were NGC, they must've came very late in the production year.
 

Sherman Bird

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When I did the head gaskets on mine, I had to check because the timing chain set listed 2 different ones, with different reluctor wheels on the camshaft.

There was a difference in the plugs on the ecm as well, 3 or 4 plugs IIRC.

If any engines were NGC, they must've came very late in the production year.
My block casting ends in "AE-1" This is the "new" reman engine
 
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HEMIMANN

HEMIMANN

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God Dammit! They don't fit the 6.4L!!!

Best we can figure - 5.7L originally came with EGR that tapped driver side exhaust manifold for supply of exhaust gas to the intake. They made a change and got rid of the EGR sometime back for some reason (I'd guess it was when they went to high voltage ignition and got rid of their waste spark ignition that used leftover ignition coils from previous engines).

At that point, they also re-cast the driver side exhaust manifold to get rid of the tapped boss, undoubtedly to save a few bucks in casting and machining cost.

But they never changed the 6.4L! So aftermarket exhaust manifold does not fit driver's side 6.4L engines. JFC And the 6.4L has a lower compression ratio than the 5.7L that would further eliminate the need for EGR in the 1st place. (EGR is used to reduce high temp NOx in exhaust gases).

Guys have put cheap shorty headers on that eventually break too, and don't provide any extra torque, and melt components. So I'm not gonna do that.

So, I'm returning the BD Diesel Exhaust Manifolds and milling down the OEM factory ones.

What a crock of $hit. All for a bad design in the 1st place.
 

NCRaineman

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Could you get 392 manifolds from a Charger/Challenger? Supposedly those are better than stock and some of the car guys are using them for a less expensive option to true headers.
 
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HEMIMANN

HEMIMANN

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Could you get 392 manifolds from a Charger/Challenger? Supposedly those are better than stock and some of the car guys are using them for a less expensive option to true headers.

Don't see any crossover to fit into the deep frame rails of the heavy duty truck - not just deeper for the high load, but also to handle the height of the Cummins 6.7 diesel. The squished the Hemi engines way down into those high rails to fit.

The truck is on a hoist at the shop right now anyway.
 

Wild one

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God Dammit! They don't fit the 6.4L!!!

Best we can figure - 5.7L originally came with EGR that tapped driver side exhaust manifold for supply of exhaust gas to the intake. They made a change and got rid of the EGR sometime back for some reason (I'd guess it was when they went to high voltage ignition and got rid of their waste spark ignition that used leftover ignition coils from previous engines).

At that point, they also re-cast the driver side exhaust manifold to get rid of the tapped boss, undoubtedly to save a few bucks in casting and machining cost.

But they never changed the 6.4L! So aftermarket exhaust manifold does not fit driver's side 6.4L engines. JFC And the 6.4L has a lower compression ratio than the 5.7L that would further eliminate the need for EGR in the 1st place. (EGR is used to reduce high temp NOx in exhaust gases).

Guys have put cheap shorty headers on that eventually break too, and don't provide any extra torque, and melt components. So I'm not gonna do that.

So, I'm returning the BD Diesel Exhaust Manifolds and milling down the OEM factory ones.

What a crock of $hit. All for a bad design in the 1st place.
I think the egr went by the wayside with the advent of variable valve timing ,the 5.7 became efficient enough to pass the emission tests with out egr. It's easy enough to delete on the 6.4's,but the downside is you'll need to tune it,as the engine will run lean with-out it.I was under the impression they kept it more for combustion chamber cooling on the 6.4's,not for nox emissions
 
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HEMIMANN

HEMIMANN

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I think the egr went by the wayside with the advent of variable valve timing ,the 5.7 became efficient enough to pass the emission tests with out egr. It's easy enough to delete on the 6.4's,but the downside is you'll need to tune it,as the engine will run lean with-out it.I was under the impression they kept it more for combustion chamber cooling on the 6.4's,not for nox emissions

But why? The 6.4L already has a lower compression ratio than the 5.7L. Should already run cooler, plus they all have piston oil squirters.

I'm not re-tuning this thing. I spent a bunch of last summer tuning and re-tuning the motorcycle after screw-ups by incompetent vendors. Done with that.

Anyway, salvage actions are underway, my local shop DOES know a manifold planer, unlike the custom exhaust shop that would have run into the same issue, and didn't know of any planer shops.

So, it's either replace with another factory set that will break, or plane these flat. Long tube headers ARH over $2,000. No. Not racing a heavy duty pickup truck.
 

Wild one

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But why? The 6.4L already has a lower compression ratio than the 5.7L. Should already run cooler, plus they all have piston oil squirters.

I'm not re-tuning this thing. I spent a bunch of last summer tuning and re-tuning the motorcycle after screw-ups by incompetent vendors. Done with that.

Anyway, salvage actions are underway, my local shop DOES know a manifold planer, unlike the custom exhaust shop that would have run into the same issue, and didn't know of any planer shops.

So, it's either replace with another factory set that will break, or plane these flat. Long tube headers ARH over $2,000. No. Not racing a heavy duty pickup truck.
According to this article the truck 6.4 is designed to run at full torque for 12 minutes on 87 octane,so i'm guessing the rumour about using the egr to keep the combustion chamber cooler and to help keep denotation to a mininium,has some merit.


"It's also worth noting that the BGE 392 piston differs from Apache piston in that its top ring land is lower than the one in the Apache 392 (Ram engineers needed the BGE 392 to be rated for full torque on 87 octane for 12 minutes at a time). "
 

crackerjack1957

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But why? The 6.4L already has a lower compression ratio than the 5.7L. Should already run cooler, plus they all have piston oil squirters.

I'm not re-tuning this thing. I spent a bunch of last summer tuning and re-tuning the motorcycle after screw-ups by incompetent vendors. Done with that.

Anyway, salvage actions are underway, my local shop DOES know a manifold planer, unlike the custom exhaust shop that would have run into the same issue, and didn't know of any planer shops.

So, it's either replace with another factory set that will break, or plane these flat. Long tube headers ARH over $2,000. No. Not racing a heavy duty pickup truck.
Any broken bolts/studs or just warpage?
 

emjohn4

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I should never have gotten hearing aids.
I can hear wife nagging again too.
The best part of when I had covid? I pretty much lost my hearing. It was glorious. Cars were quiet, they didn't rattle, and the wife was happy (must have been, didn't hear any complaints). :)

Sadly, my hearing returned.
 
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HEMIMANN

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According to this article the truck 6.4 is designed to run at full torque for 12 minutes on 87 octane,so i'm guessing the rumour about using the egr to keep the combustion chamber cooler and to help keep denotation to a mininium,has some merit.


"It's also worth noting that the BGE 392 piston differs from Apache piston in that its top ring land is lower than the one in the Apache 392 (Ram engineers needed the BGE 392 to be rated for full torque on 87 octane for 12 minutes at a time). "

Yeah, I read about the octane strategies.
 
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HEMIMANN

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Any broken bolts/studs or just warpage?

I didn't get that far today - pulling wheels / wells and comparing manifolds led to this nastiness 1st - I got the call @ 1PM, worked on it until day's end. I have other parts coming in overnight from Summit Racing.

It is at least warped, by evidence of loud startup barking in cold weather (deer hunt camp this fall) then, quieting down after warmup. That's all I need to know for now.
 
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HEMIMANN

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It's getting better - the air expedited gaskets don't fit either. Rem Flex 6022 does NOT fit 6.4L BGE Hemi in Ram 2500 trucks. Hole pattern totally different. WTF
 
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HEMIMANN

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After literally running around for hours and days, here is what I found -

For the 6.4L Hemi (BGE) Ram Truck Engine:

NO aftermarket exhaust manifolds exist - none, zero, zilch, nada - not in plain manifolds or shorty headers. The ONLY aftermarket manifold is a full ARH long tube stainless exist system for $2,000 just for the parts, add labor and re-tuning to the bill. No thank you. The only option is to sand down your stock bosses flat, or order new stock you'll have to sand down again later anyway.

NO aftermarket exhaust gaskets exist - not Remflex or FelPro or anybody else. NONE. Had to order a new set of MOPAR gaskets.

ARH does NOT make aftermarket manifold hardware for this engine. The ONLY choices are MOPAR or Dorman. I went with Dorman because they have optional stainless and drylock patches.

What a crock of $hit for something that should never fail from the factory in the first place. All sorts of incorrect catalogues with misinformation out there.
 

Sherman Bird

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After literally running around for hours and days, here is what I found -

For the 6.4L Hemi (BGE) Ram Truck Engine:

NO aftermarket exhaust manifolds exist - none, zero, zilch, nada - not in plain manifolds or shorty headers. The ONLY aftermarket manifold is a full ARH long tube stainless exist system for $2,000 just for the parts, add labor and re-tuning to the bill. No thank you. The only option is to sand down your stock bosses flat, or order new stock you'll have to sand down again later anyway.

NO aftermarket exhaust gaskets exist - not Remflex or FelPro or anybody else. NONE. Had to order a new set of MOPAR gaskets.

ARH does NOT make aftermarket manifold hardware for this engine. The ONLY choices are MOPAR or Dorman. I went with Dorman because they have optional stainless and drylock patches.

What a crock of $hit for something that should never fail from the factory in the first place. All sorts of incorrect catalogues with misinformation out there.
Remember the Cadillac HT-4100 of yore? I repaired DOZENS of leaky exhaust manifolds like such: I'd remove the manifolds and broken bolts from the heads. Then, I'd clean the head surfaces meticulously. I took the manifolds to a machine shop (He recently shut down and retired), and have the manifolds surface ground to a very smooth finish.... Now, HERE'S the REAL clever trick... An old long of tooth geezer, ex-mechanic told me to PAINT the exhaust surface with high temp paint, and put on a thick coat. Let it get tacky, and install it with NO gasket, and torque it down. Then run the engine for about a minute or 2, shut it off, and repeat 2 times. Let it "Cure" for a couple of hours. I did that trick many times and NEVER had a single one fail.
 
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