Do i want OEM exhaust manifolds?

[Tom's EK2]

Hello,
Got my AAR back on the road in November last year. I've got a whole new list of "to do" stuff now. I'm considering going back to stock exhaust, thinking about just getting them and maybe switch later. So...
I'm looking around for a decent pair. They don't need to be date correct or anything, just nice, period correct. Any way, there is a pair on E Bay and I'm just wondering why no one is buying them. I've spoke with the seller and he will take less. You can look at them if you want.
1968-1970 MOPAR 340 HP EXHAUST MANIFOLDS AAR T/A CHALLENGER DUSTER OEM RARE
The seller is smileanywayz(711).
Let me know what you think or if someone has a nice set. THANKS-TOM

 

[pschlosser]

I can see a few reasons why "no one is buying them."

They are deeply pitted, even on the mating surfaces of the manifold to the head. This suggests they've been lying on the ground in a muddy swamp, or the "north 40" of some back water farm, for 10 years or more. It takes time and exposure to get them that deeply pitted.

They are black, very dark black oxide, even on the mating surfaces to the head. This suggests a rust treatment, like any of the common phosphoric acid products, example navel jelly, to get them respectable-looking again. I'd be surprised if the heat riser valve wasn't frozen.

He is asking high numbers for them, close to twice what (average ones) may be worth. These may have been available reproduction, not too far back. But the supply may be dry. If you want a set of these, keep your eyes open.

They are not terribly rare. They were the manifolds that came on all 340 engines, from 1967 to 1971-ish. They are a decent manifold, but not some special high performance version of a low performing manifold. These were it. But they were also used on the prestigious 1970 340-6 AAR and T/A motors.

I might be tempted to pay $1200 for a nice set, that looks something like:

Do you want these over headers? Maybe. You'll give up some horsepower, maybe 20-30 HP. Maybe less. And mods to your existing pipe. If you have a genuine AAR, it may be worth the loss. But only when it comes time to sell or show. If you don't have a set of the manifolds, it may be wise to seek a set out, so you have some options down the road.

 

[Ricks72Chlgr440]

View attachment 133746
Hello,
Got my AAR back on the road in November last year. I've got a whole new list of "to do" stuff now. I'm considering going back to stock exhaust, thinking about just getting them and maybe switch later. So...
I'm looking around for a decent pair. They don't need to be date correct or anything, just nice, period correct. Any way, there is a pair on E Bay and I'm just wondering why no one is buying them. I've spoke with the seller and he will take less. You can look at them if you want.
1968-1970 MOPAR 340 HP EXHAUST MANIFOLDS AAR T/A CHALLENGER DUSTER OEM RARE
The seller is smileanywayz(711).
Let me know what you think or if someone has a nice set. THANKS-TOM

Some absolutely HATE headers, some love them. What headers are you using now, and why are you considering going back to OE style exhaust? There are headers out there that do not have the fitment and ground clearance issues some others have.

 

[Tom's EK2]

View attachment 133750
I can see a few reasons why "no one is buying them."

They are deeply pitted, even on the mating surfaces of the manifold to the head. This suggests they've been lying on the ground in a muddy swamp, or the "north 40" of some back water farm, for 10 years or more. It takes time and exposure to get them that deeply pitted.

They are black, very dark black oxide, even on the mating surfaces to the head. This suggests a rust treatment, like any of the common phosphoric acid products, example navel jelly, to get them respectable-looking again. I'd be surprised if the heat riser valve wasn't frozen.

He is asking high numbers for them, closer to twice what they may be worth. These may have been available reproduction, not too far back. But the supply may be dry. If you want a set of these, keep you eyes open.

They are not terribly rare. They were the manifolds that came on all 340 engines, from 1967 to 1971-ish. They are a decent manifold, but not some special high performance version of a low performing manifold. These were it. But they were also used on the prestigious 1970 340-6 AAR and T/A motors.

I might be tempted to pay $1200 for a nice set, that looks something like:
View attachment 133749

Do you want these over headers? Maybe. You'll give up some horsepower, maybe 20-30 HP. Maybe less. And mods to your existing pipe. If you have a genuine AAR, it may be worth the loss. But only when it comes time to sell or show. If you don't have a set of the manifolds, it may be wise to seek a set out, so you have some options down the road.

Exactly what I was wanting to know. THANKS
I may want to switch later. I'll have to wait for spring around here in Indiana. Get a few more miles on the car.

 

[Tom's EK2]

Some absolutely HATE headers, some love them. What headers are you using now, and why are you considering going back to OE style exhaust? There are headers out there that do not have the fitment and ground clearance issues some others

Some absolutely HATE headers, some love them. What headers are you using now, and why are you considering going back to OE style exhaust? There are headers out there that do not have the fitment and ground clearance issues some others have.

Thanks
I went with some cheap shorty style headers that go under the steering link. I don't care for the look of the headers being down so low and an exhaust leak issues.

 

[Ricks72Chlgr440]

Thanks
I went with some cheap shorty style headers that go under the steering link. I don't care for the look of the headers being down so low and an exhaust leak issues.

Shorty headers can be good in some applications but they won't deliver the goods that long tube headers can provide. I've used the Dougs D453 on my 408 stroker small block and they were excellent. I used them with Remflex exhaust gaskets and no leaks. They are not the cheapest around but I got what I paid for. Ground clearance had no issues either since they went above the drag link.
Edit: the only issue I had with those headers was when I upgraded my torsion bars from stock to 1.03. I had to clearance a couple of the tubes. Other than that, they were great.

 

[Xcudame]

Oh my goodness, I've got a pair of 70 (69 casting date) 340 exhaust manifolds hanging on my barn wall! Didn't know they were $1200 worth!!

 

[Ricks72Chlgr440]

Oh my goodness, I've got a pair of 70 (69 casting date) 340 exhaust manifolds hanging on my barn wall! Didn't know they were $1200 worth!!

With that dry climate they are no doubt in great shape too!!!

 

[Tom's EK2]

Shorty headers can be good in some applications but they won't deliver the goods that long tube headers can provide. I've used the Dougs D453 on my 408 stroker small block and they were excellent. I used them with Remflex exhaust gaskets and no leaks. They are not the cheapest around but I got what I paid for. Ground clearance had no issues either since they went above the drag link.
Edit: the only issue I had with those headers was when I upgraded my torsion bars from stock to 1.03. I had to clearance a couple of the tubes. Other than that, they were great.

Excellent
Thanks- I'm not 100 percent sure what I'm going to change yet if anything. The car has plenty of get up and go. 340 stroked to 413 and 391 gears. She's a true vitamin C AAR with an original white interior. The original drive train is long gone and no build sheets. Dash Vin and fender tags only
Maybe just buy a set of original exhaust manifolds for later.

 

[Tom's EK2]

Oh my goodness, I've got a pair of 70 (69 casting date) 340 exhaust manifolds hanging on my barn wall! Didn't know they were $1200 worth!!

Really? For sale?

 

[Stev-o]

Post a pic of your headers, would like to see them

 

[Xcudame]

So you know I'm not crazy (too much). They are literally just hanging on the wall! I was going the 340 route for my 71 Barracuda until my son talked me into putting a 440 in it. I even have a complete 340 short bock (.020" over) and iron heads with 2.08 intake and 1.60 exhaust and steel rocker arms. Plus 2 more blocks, 2 forged crankshafts and 2 sets of floating connecting rods. I could probably refurbish my Barracuda with 340 parts!

 

[Tom's EK2]

Post a pic of your headers, would like to see them

Post a pic of your headers, would like to see them

 

[Tom's EK2]

View attachment 133755View attachment 133756View attachment 133757

Yeah....The oil leak is on my new to do list.
Change blinker/flasher to LED type bulbs, and a few more things to do.

 

[pschlosser]

You might actually gain horsepower, going to properly fitting long headers.

 

[Ricks72Chlgr440]

Excellent
Thanks- I'm not 100 percent sure what I'm going to change yet if anything. The car has plenty of get up and go. 340 stroked to 413 and 391 gears. She's a true vitamin C AAR with an original white interior. The original drive train is long gone and no build sheets. Dash Vin and fender tags only
Maybe just buy a set of original exhaust manifolds for later.

With an engine like that you will gain a nice bit of torque with long tube headers & good flowing mufflers. Depending on how the rest of the engine is built, a stroked small block like you have would certainly enjoy better headers! The 408 in my Duster (with 3500 stall converter, 3.55 gears, and 275/60/15 tires) would spin the tires if I nailed it at 40mph. Was fun to drive! Sold that car to buy my Challenger!

 

[Tom's EK2]

Thanks, that's another option.

 

[Tom's EK2]

With an engine like that you will gain a nice bit of torque with long tube headers & good flowing mufflers. Depending on how the rest of the engine is built, a stroked small block like you have would certainly enjoy better headers! The 408 in my Duster (with 3500 stall converter, 3.55 gears, and 275/60/15 tires) would spin the tires if I nailed it at 40mph. Was fun to drive! Sold that car to buy my Challenger!

Not sure about more horse power yet. She'll break the tire loose at 30 and get it.

 

[pschlosser]

maybe the gain would be so tiny, only a dyno could see it, but a longer pipe would be more efficient, give you better undercarriage clearance, and sound marginally better. Is it worth the added expense and heartache to change? Maybe not... yet! Give it time.

 

[Tom's EK2]

maybe the gain would be so tiny, only a dyno could see it, but a longer pipe would be more efficient, give you better undercarriage clearance, and sound marginally better. Is it worth the added expense and heartache to change? Maybe not... yet! Give it time.

Thanks- that's what I'll be doing,giving it more time to consider. But... I may post a WTB for the correct exhaust manifolds.