340 exhaust manifolds

[nsmall]

Is there a difference between 318 and 340 exhaust manifolds?

I have a 1973 340 and I was told I may have 318 manifolds.

If there is such a thing as a 340 manifold I'm assuming it offers more flow than a 318?

There are some 340 manifolds on eBay and they're claiming their high performance but I'm assuming all of them are considered high performance as 340s are more of the High Performance Engine....Right?

Thanks

[1 Wild R/T]

71 & up 340 manifolds are not the same as 68-70... 71 & up are more of a log design.. 68-70 are considered the Hipo manifolds.. I just looked on Ebay
& didn't see any 68-70 manifolds

[6bblgt]

1973 e-body 340 casting numbers:
RH = 3418623 (part # 3418624)
LH = ?? (part # 3751083)

1973 e-body 318 casting numbers:
RH = 2843953 (part # 2843966)
LH = 3512077 (part #3512076)

what casting numbers do you have, got pics?

[YellowThumper]

Port openings are considerably larger for the 340.
I had 340 J heads on my 318 in the past with 360 ex manifolds. California smog check nailed me long ago and I had to remove heads and put my old 318s on. I left the 360 manifolds on and flat area on the 318 port openings barely went as far as the opening on manifolds.

[anlauto]

Visually not much difference in 1973, but port size, yes 340's are larger.

[CudaMoparRay]

Great info as have been debating taking off my Hooker Competition headers and replacing with OEMish exhaust manifolds.

[nsmall]

@CudaMoparRay

Sounds like 68-70 OEM manifolds are what we want.

[1 Wild R/T]

They are reproduced...

https://www.yearone.com/Product/chrysler-a-body/ae340 

[CudaMoparRay]

They are reproduced...

https://www.yearone.com/Product/chrysler-a-body/ae340

Just the ticket it seems as compared to finding OEM used hipo ones

[nsmall]

They are reproduced...

https://www.yearone.com/Product/chrysler-a-body/ae340

Just the ticket it seems as compared to finding OEM used hipo ones

Counting shipping it's $800 bucks.  Sigh

[moparmadman69]

@CudaMoparRay

Sounds like 68-70 OEM manifolds are what we want.

Just remember if you run the 70 HP manifolds you have to use a 90 degree oil filter adapter to fit that right manifold. Left there is no clearance issues.

Colby

[rocketresto]

Shakerhood.com and Northwest Performance is the actual maker of the manifolds and we do not charge Year One shipping prices.  Our retail price is $600 a pair - give us a call if you want to order them.  360-943-6633

[Topcat]

They are reproduced...

https://www.yearone.com/Product/chrysler-a-body/ae340

For 50 bucks less from Shakerhood.com

Before Ben passed away, he told me he was the one responsible getting them reproduced.

http://www.shakerhood.com/products.php?id=ExhaustManifolds

[CudaMoparRay]

Shakerhood.com and Northwest Performance is the actual maker of the manifolds and we do not charge Year One shipping prices.  Our retail price is $600 a pair - give us a call if you want to order them.  360-943-6633

Extremely tempting

[rocketresto]

They are reproduced...

https://www.yearone.com/Product/chrysler-a-body/ae340

For 50 bucks less from Shakerhood.com

Before Ben passed away, he told me he was the one responsible getting them reproduced.

Correct - buy them from the source!

http://www.shakerhood.com/products.php?id=ExhaustManifolds