New to 340 so I have questions

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AZ-Nick

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I’m in my 70’s and I am not going to the track anymore I am just looking at driving around and cruising to the shows.

I just picked up a 69 340 swinger, first time I ever owned a 340, always had Big Blocks for the last 55yrs.
The owner of this car passed away and I don’t know any history of it.

Question 1. I can’t tell if it has been cammed or not because I have no idea what a 340 with a stock cam sounds like. I’ve been told that the 340 came stock with a small upgrade in a came, upgrade to what? That sounds odd to me. Any ideas on how I can figure out what is going on with this motor?

The motor in my car sounds like it has a tittle cam in it but is it stock or upgraded, I can’t tell, motor looks like it has some new gaskets on it. It also has headers, Performer intake, edelbrock 1806S, and MSD ignition system and distributor. I also noticed that the subframes are connected to each other so I am sure it could have been on the track at some time.

Question 2. I have a date code original manifold and a few other carburetors, do you think that the Performer manifold and Edelbrock carb is a good combination or should I just go back to the original manifold and Carter AVS?

Sorry for the long winded conversation.
Thanks Nick
 
Stock 340s had relatively big cams (long duration with 44 to 52 degrees overlap) in them and they did idle rougher than most other MOPAR engines other than HEMIs. Stock ones ran great and the stock intake with the AVS worked very well and still do. At 750 to 900 rpm, they do thump a bit and with headers it should be noticeable. I doubt though yours has the stock cam if someone has already installed headers and changed the intake.
 
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Are you happy with how it runs? Does it do everything you’re asking it to do? Would you like it to act a different way than it does currently? Those are the questions you should be asking yourself. If it does everything you’d like it to do then it makes no difference what parts are on or in it.
 
I just want to add that the 340 was Chrysler's new Performance engine. The cams weren't upgraded, just a performance part of the package. That '69 when new would have high compression pistons as well, about 10.5 to 1. It should have a lumpy idle as mentioned. It sounds like the previous owner did some performance upgrades over the stock setup.
 
VOETOM said:
Stock 340s had relatively big cams (long duration with 44 to 52 degrees overlap) in them and they did idle rougher than most other MOPAR engines other than HEMIs. Stock ones ran great and the stock intake with the AVS worked very well and still do. At 750 to 900 rpm, they do thump a nit and with headers it should be noticeable. I doubt though yours has the stock cam if someone has already installed headers and changed the intake.
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Thanks for the info, I never knew much about them. And yes the thump is very noticeable with the headers and the fake Flowmasters.
 
If it doesn't have the electronic ignition it would be a valuable piece to put in. I had a 71 340 Duster and it had the single point Distributor and I went to the electronic ignition and it really woke that motor up. Good luck with your new ride.
 
413 said:
How much idle vacuum does it have?
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Never checked, is there a certain spot I should check at, and what amount are you thinking there should be? I will check it on Friday or Saturday and get back to you.
 
TT5.9mag said:
Are you happy with how it runs? Does it do everything you’re asking it to do? Would you like it to act a different way than it does currently? Those are the questions you should be asking yourself. If it does everything you’d like it to do then it makes no difference what parts are on or in it.
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Unfortunately it is hard to say am I happy with it because I am not sure if it is running correctly or not.
I just sold a 600hp at the rear wheels car so this is a real different type of car for me.
 
Woodys_Cuda said:
I just want to add that the 340 was Chrysler's new Performance engine. The cams weren't upgraded, just a performance part of the package. That '69 when new would have high compression pistons as well, about 10.5 to 1. It should have a lumpy idle as mentioned. It sounds like the previous owner did some performance upgrades over the stock setup.
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Thanks for the information, this helps me understand what I am working with.
 
tonysrt said:
If it doesn't have the electronic ignition it would be a valuable piece to put in. I had a 71 340 Duster and it had the single point Distributor and I went to the electronic ignition and it really woke that motor up. Good luck with your new ride.
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Thanks for your input but it is all MSD.
 
This is my Swinger.

IMG_4408.jpeg


IMG_4405.jpeg


IMG_4404.jpeg
 
MSD is good. I put a complete MSD system (Distributor, box, coil and plug wires) in my 69 340 Barracuda, and it was a game changer. It starts way easier, it idles better and I can feel an increase off the line.
 
AZ-Nick said:
Unfortunately it is hard to say am I happy with it because I am not sure if it is running correctly or not.
I just sold a 600hp at the rear wheels car so this is a real different type of car for me.
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Like any new (to you) car you should probably go through and check a few things out. Compression check, verify rocker adjustment (preload for hydraulics or lash for solids), pull the plugs and get an eye on em and then stick a timing light on it and verify the timing. A good “once over” just to make sure nothing is crazy out of whack and then you can at least be sure it’s running up to what it’s capable of.
 
That's a really nice looking car, Nick! Could you maybe shoot us a little video of it running from behind so we can get some exhaust note? That would really help. You will need to upload it to a hosting site like youtube and then post the link here.
 
RustyRatRod said:
That's a really nice looking car, Nick! Could you maybe shoot us a little video of it running from behind so we can get some exhaust note? That would really help. You will need to upload it to a hosting site like youtube and then post the link here.
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I definitely can take the video on a cold start or warm start, what ever you think is best to do but I have no idea where to begin on uploading it to a hosting site. I will look into how to do that with you tube. It won’t happen until after thanksgiving.
 
AZ-Nick said:
I definitely can take the video on a cold start or warm start, what ever you think is best to do but I have no idea where to begin on uploading it to a hosting site. I will look into how to do that with you tube. It won’t happen until after thanksgiving.
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Either cold or hot. We can tell either way. All you need is the basic FREE youtube account. No need for anything more. We'll be lookin for it!
 
Bodyperson said:
Some of that information is wrong or the format got screwed up. I don't think the factory came out with a half inch cam and some of the valve size values are screwed up.
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No forged steel pistons either.
 
Bodyperson said:
Some of that information is wrong or the format got screwed up. I don't think the factory came out with a half inch cam and some of the valve size values are screwed up.
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Ohh thanks.. that's what I get for speed reading and not checking the article first. This looks better:
1968-1970
  • Big 2.02 inch intake valves and 1.60 inch exhaust valves, vs the 318's 1.78 intake and 1.50 exhaust
  • • ‘206’ hydraulic cam - 268 in. dur. - 276 ex. dur. 44 overlap (in 1968, only the 4 speed cars got a more aggressive cam, automatic versions got a cam that become the standard in these hi-performance engines)
  • Aluminum pistons
 
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