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
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
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?
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.
Visually not much difference in 1973, but port size, yes 340's are larger. :alan2cents:
Great info as have been debating taking off my Hooker Competition headers and replacing with OEMish exhaust manifolds.
They are reproduced...
https://www.yearone.com/Product/chrysler-a-body/ae340
Quote from: 1 Wild R/T on April 28, 2017, 07:57:11 PM
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
Quote from: CudaMoparRay on April 30, 2017, 12:57:55 PM
Quote from: 1 Wild R/T on April 28, 2017, 07:57:11 PM
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
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
Quote from: 1 Wild R/T on April 28, 2017, 07:57:11 PM
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
Quote from: rocketresto on May 01, 2017, 04:32:06 PM
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
Quote from: Topcat on May 01, 2017, 06:58:56 PM
Quote from: 1 Wild R/T on April 28, 2017, 07:57:11 PM
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
Lots of the original ones are cracked, so the repro ones don't seem like too bad of a buy.
Are the original 73 340 manifolds big port log style on both sides OR hipo style w/ cast in heat stove flange on drivers and log on passenger side.
The 72-74 340-360 ebody cars originally have air cleaners with heat stoves.
Quote from: rocketresto on May 01, 2017, 07:45:01 PM
Quote from: Topcat on May 01, 2017, 06:58:56 PM
Quote from: 1 Wild R/T on April 28, 2017, 07:57:11 PM
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
I just wanted to verify what you said is true is why I posted. :slapme5:
casting numbers are usually different than part numbers (often by just one)
I didn't have the casting number for the 1973 LH manifold - THANKS!!
1973 e-body 340 casting numbers:
RH = 3418623 (part # 3418624)
LH = 3751084 (part # 3751083) - also used on '74 360s
casting number represents the part "as cast", part number represents the part "as needed for assembly" after machining/chroming/painting or any other operation a part may need
some casting numbers can be used for more than one final part number, mid-'70s 440 intake manifolds come to mind
Quote from: nsmall on May 02, 2017, 11:44:48 PM
Quote from: nsmall on May 02, 2017, 10:14:55 PM
@6bblgt (https://forum.e-bodies.org/mlist/6bblgt_211) @rocketresto (https://forum.e-bodies.org/mlist/rocketresto_130)
Thanks for the offer rocketresto. I'll consider. Considering headers also.
Not sure how much of a difference 68 - 70 manifolds are vs 1973. Is there any actual data on this as I do want more flow since I have a fairly High Performance 340.
but I'm still debating the header situation. Not sure it's worth all the money and time but I do like horsepower.
Headers require more maintenance overall.
They heat up the floor boards and front cabin alot more.
Gaskets blow out and then you get that annoying header leak sound. :pullinghair:
All rubber and plastic parts take a beating from the additional heat they put out.
More decibels entering cabin while accelerating. After a while it gets to be too much for a long drive.
Ground clearance with most brands are a major problem. TTI headers have the best clearance but are very expensive.
One pipe goes under the idler arm. I call this the speed bump pipe. It never fails: one high spot on the road and Bam! Game over!
Headers will definitely make more power but at what cost? Peace of mind?
http://www.hotrod.com/articles/mopp-0106-manifolds-vs-headers/
Another option that works well is 5.9 Magnum truck manifolds....
I have TTI headers....1 and 5/8 that have 3 inch collectors.
I guess the question I'm trying to ask is.....is stock exhaust 2 inches on a 1973 340 Ebody?
Darren....you copy?
@Burdar (https://forum.e-bodies.org/mlist/burdar_173)
If you are in a pinch to ge it together. Use your current manifolds with the 2 inch. Then right after the connection have pipes expanded to the diameter you want run to the back. With a functional system you can then decide where to go afterwards. Headers or time to search for manifolds of choice. You only then have to change out the head pipe.
My2c Mike.
Lots of times, the factory used a smaller diameter pipe right off of the manifolds. Then, once the pipe got past the starter, shift linkage and oil filter, it expanded to a larger size. My guess is that the factory pipe on the manifold was 2". Somewhere along side the trans, it expands to 2 1/4" OD. Most of the system is probably 2 1/4".
I don't see a problem with using a reducer and connecting your headers to a 2 1/4" system since you already have it. Save some money and use your existing system so you can get the car on the road. Then in a couple years, you can upgrade to a 2 1/2" system. :alan2cents:
It was actually proven to increase power the other way around with larger pipes off of the manifolds & reducing toward the tips as the exhaust cools
I have a 71 340, went with TTI SHORTYS about the same price as OEM manifolds. TTI's fit very well.
Quote from: Burdar on October 01, 2017, 05:59:31 PM
Lots of times, the factory used a smaller diameter pipe right off of the manifolds. Then, once the pipe got past the starter, shift linkage and oil filter, it expanded to a larger size. My guess is that the factory pipe on the manifold was 2". Somewhere along side the trans, it expands to 2 1/4" OD. Most of the system is probably 2 1/4".
I don't see a problem with using a reducer and connecting your headers to a 2 1/4" system since you already have it. Save some money and use your existing system so you can get the car on the road. Then in a couple years, you can upgrade to a 2 1/2" system. :alan2cents:
Factory exhaust was 2.00" off the manifolds for about 16" then they went into 2.25" all the way to the mufflers back by the gas tanks and exited the muffler in a 2" tip.