New to 340 so I have questions

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I would just drive and enjoy it ,Just my opinion

100% and a big AMEN!

It's a gorgeous car. How about some more pics...a general all-round and inside show?

To the 'add this/check that' parts...why? 11" of vacuum is terrific! My 340 runs 5-6"...and the brakes work just fine (vacuum brakes), so what's to fuss with? If yours uses a quart of oil every six months? Big deal. With that much vacuum, there's not much wrong with it to worry about. That figure can most certainly get higher with a decent tune, too. If it can't, SO WHAT?

I'M your age. I'm interested much more in driving around than rebuilding anything OR fussing with this-n-that.

DRIVE it! Have FUN with it.

Certainly, a tune-up is a good idea. If it's not broke, don't fix it.

Disk brakes (master doesn't look like it)? What rear? If most of it's stock-ish... there aint' NOTHIN' wrong with that!!

WILL it run better with 'more'? Sure. Not necessary! I ran 11's with a 650 Holley. Your 650 AVS is just fine. Very tunable, too. Hint: ALWAYS stuff something in the carb if you take the needles out!! You don't want any, 'I heard a 'sproing'...but I can't find the spring,' going on.

Fantastic. Good job. Excellent car!! I'd be so tickled pink at such a car I couldn't stand it. I LOVE that year!!

Only thing it's missing is an 833!! ;)


Uh...isn't 'Nick' the guy that was never going to own a 340? I may be wrong 'bout that.
 
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great looking car , if the power brakes work you most probably have a stock or close to stock cam . Good shocks with sway bars you will have a car that is fun to drive on the back roads , that s how I set mine up , a blast to drive back roads or a track . These A bodies are a blast on the road. Good luck and have fun
 
good question, I am still trying to figure that out too.
The odometer reads around 64k, but that still doesn't mean anything.
The heads are X heads, that's for sure, I spotted the X immediately.
I want to check the block, I was told to check it like a big block at the pan rail, but I can't get on the ground to check it because of my bad hip and knees, (Replaced) it's too painful and I can't get up.
I was told to check the casting number, but I can't seem to find it because of the header in the way.

Next time you take it in for an oil change ask the mechanic to snap a pic of the casting numbers right above the starter on the drivers side under cylinder #5

IMG_1542.jpeg


On the passenger side there is a date the block was cast, it is towards the front right under cylinder #2 where the block meets the head

IMG_1543.jpeg


IMG_1544.jpeg
 
Next time you take it in for an oil change ask the mechanic to snap a pic of the casting numbers right above the starter on the drivers side under cylinder #5

View attachment 1716170708

On the passenger side there is a date the block was cast, it is towards the front right under cylinder #2 where the block meets the head

View attachment 1716170709

View attachment 1716170710
Thank you for your reply and pictures of the locations.
I was able to get a hanging light down near the firewall and a 2” round telescoping mirror down between the header tubes and with an additional high intensity flashlight aimed at the mirror I was able to identify only the following “-340-?” It was impossible for me to get a picture of the 340 because I needed to hold the mirror in one hand and the flashlight in the other hand. So far it is a 340, that is Great. What is upsetting if the next thing I saw is correct is below the #2 cylinder, in the mirror as in the picture it is upside down but it looks like 7*70.
Correct me if I am wrong!
I will try tomorrow to get the remaining casting numbers that are before the-340-?

IMG_4446.jpeg


IMG_4445.jpeg
 
Although I'm a a little less than a couple of years away from 60, I got a very early start as a mechanic at nine years old. My body is probably ten or more years older than it really is, as I spent a long time in alignment and suspension work. That really does a number on everything below the waist, so I can certainly relate.
 
100% and a big AMEN!

It's a gorgeous car. How about some more pics...a general all-round and inside show?

Uh...isn't 'Nick' the guy that was never going to own a 340? I may be wrong 'bout that.
Nope you must have the wrong Nick, I have never said that I would never going to own a 340.
 
vacuum is 12, pretty low.
Car sounds nice. Cam doesn’t sound very agressive.
Car looks great.
I think I may have found the issue.
Two of the Nuts on one side of the carb were snug and the other two were kind of loose. Also the PCV valve was freely loose in the hard a a rock grommet that was split in two areas. I am now waiting for a new replacement grommet that I ordered online. The pcv valve was a little sticky so I cleaned it out and it now functions as it should.
 
I think I may have found the issue.
Two of the Nuts on one side of the carb were snug and the other two were kind of loose. Also the PCV valve was freely loose in the hard a a rock grommet that was split in two areas. I am now waiting for a new replacement grommet that I ordered online. The pcv valve was a little sticky so I cleaned it out and it now functions as it should.
That could very well cause some issues. Vacuum leaks are one of the #1 problems. Good luck, Nick. Keep us posted.
 
This is a stock 1969 340 with the 68 manual cam 2899205 and with electronic ignition and my vacuum mufflers, closed. This has a true Dr. Gas X pipe so it is not quite as crackly as it would be without.

This is with the mufflers open. You can hear the lope of the 68 cam here.

Sounds like my 69' Dart 4-speed. I also installed a DC 4-speed cam from a 68', when I rebuilt it. Sounds and runs great for a mostly stock motor.
 
Thank you for your reply and pictures of the locations.
I was able to get a hanging light down near the firewall and a 2” round telescoping mirror down between the header tubes and with an additional high intensity flashlight aimed at the mirror I was able to identify only the following “-340-?” It was impossible for me to get a picture of the 340 because I needed to hold the mirror in one hand and the flashlight in the other hand. So far it is a 340, that is Great. What is upsetting if the next thing I saw is correct is below the #2 cylinder, in the mirror as in the picture it is upside down but it looks like 7*70.
Correct me if I am wrong!
I will try tomorrow to get the remaining casting numbers that are before the-340-?

View attachment 1716170833

View attachment 1716170834
Next time you take it in for an oil change ask the mechanic to snap a pic of the casting numbers right above the starter on the drivers side under cylinder #5

View attachment 1716170708

On the passenger side there is a date the block was cast, it is towards the front right under cylinder #2 where the block meets the head

View attachment 1716170709

View attachment 1716170710
Okay I had to be a Contortionist but I did manage to get all of the block casting number's but the first number. They are
*780930-340-8. It looks too be a 340 block with the X heads.
 
Yes the number confirms it is definitely a 340. The -8 indicates that it was the 8 time that the casting mold was used.

I am not sure what the numbers before the 340 mean.

The casting date is on the passenger side under the #2 spark plug.

Blocks cast in 67,68,69 and part of 70 were candidates for the X heads. In 71 the J head was introduced. I read somewhere the j heads were used on 340 six packs with 2.02 valves.

Here is a thread about the heads.
X-heads vs J-heads: what's the difference??
 
I have an aftermarket cam in mine it idles smooth but revs quick. I like that I dont need the shaky lopey idle in a street car. AS long as it spins up as needed when the throttle is opened.
 
The X heads have the big valves so that's a bonus and correct for that engine.

Yeah I understand, I'll be 70 in a few months. Crawling under cars for some of us is painful now.

No big deal, it's a very nice car so just enjoy driving it. :steering:
Contrary to popular belief, the X heads are nothing special and exactly the same as batches of J and O heads providing they had the 202 valves. Later on, the valves were reduced.

On '70 340s there are 4 other castings that are technically
correct, besides the 'X head. They are 0, U, Z and 'J castings
Some very late '70 340s got J' castings that have a 'U on the
underside, some also were 'J' all around, in very late 70 model
year.

The X symbol was added to the casting molds because the 340 heads were getting mixed up with the smaller valve 318 heads at the foundry. The X, J and O heads were simply different batch numbers of the same casting molds. I have a 1970 early build 340 and it has the O head designation heads. I also have a 1970 340 Dart Swinger and it has the J heads.

Here is a memo from the head foundry Engineer who called for the letter designation.

1000014556.png
 
Contrary to popular belief, the X heads are nothing special and exactly the same as batches of J and O heads providing they had the 202 valves. Later on, the valves were reduced.
Thanks for the info!

The point of my post being the fact Nick's heads are correct for the '68 or '69 block .
 
There is a difference in X’s heads compared to J’s. For most people it will never matter, but here it is. The X’s were cast with the bigger valve in mind, so more clearance from the water passage, while the J’s were not. So in a pretty serious port job. You can get a bit over 10 cfm more out of an X head. Again, won’t matter to many people. Is the air filter an K&N filter? It looks like it needs to be cleaned or replaced.
 
100% and a big AMEN!

It's a gorgeous car. How about some more pics...a general all-round and inside show?

To the 'add this/check that' parts...why? 11" of vacuum is terrific! My 340 runs 5-6"...and the brakes work just fine (vacuum brakes), so what's to fuss with? If yours uses a quart of oil every six months? Big deal. With that much vacuum, there's not much wrong with it to worry about. That figure can most certainly get higher with a decent tune, too. If it can't, SO WHAT?

I'M your age. I'm interested much more in driving around than rebuilding anything OR fussing with this-n-that.

DRIVE it! Have FUN with it.

Certainly, a tune-up is a good idea. If it's not broke, don't fix it.

Disk brakes (master doesn't look like it)? What rear? If most of it's stock-ish... there aint' NOTHIN' wrong with that!!

WILL it run better with 'more'? Sure. Not necessary! I ran 11's with a 650 Holley. Your 650 AVS is just fine. Very tunable, too. Hint: ALWAYS stuff something in the carb if you take the needles out!! You don't want any, 'I heard a 'sproing'...but I can't find the spring,' going on.

Fantastic. Good job. Excellent car!! I'd be so tickled pink at such a car I couldn't stand it. I LOVE that year!!

Only thing it's missing is an 833!! ;)


Uh...isn't 'Nick' the guy that was never going to own a 340? I may be wrong 'bout that.
Very true do you want to drive it or work on it and if it isnt broke why work on it. Now I would say theres nothing wrong with trying to go faster which will lead to broken parts and a reason to work on it...:)
 
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