ryan1964
Well-Known Member
How do I figure out what year these are or if anyone know that would be great too
340 X heads
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I'd do a search in a search engine, like this... Google Search
Professor Fate
Push the button, Max...
Isn't that a casting date of 09299 (Sept. 29, 1969)?
Second shift, 7 pm...
If so, that would make them a '70 model year.
Just a S.W.A.G.
Second shift, 7 pm...
If so, that would make them a '70 model year.
Just a S.W.A.G.
ryan1964
Well-Known Member
Oh ok thanks makes sence
As my elder mind seems to recall, X heads were only
on 68 and 69 model that I have ever seen.
The 70 models that I have ever seen were J or U.
on 68 and 69 model that I have ever seen.
The 70 models that I have ever seen were J or U.
X heads were used as the switch over was happening in 1970 model year.
That's a late casting date for the period. My 70 swinger with a a dec build engine had a x on one side, J on the other.
That's a late casting date for the period. My 70 swinger with a a dec build engine had a x on one side, J on the other.
ryan1964
Well-Known Member
That's cool I've heard that could happen
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9th month, 29th day 1969.
1970 car 340.
1970 car 340.
harrisonm
Well-Known Member
I agree.
I've heard of that too. I have to wonder if there is any consistency as to which side got the J head.One of the mopar neighbors called the car "Bastard" because of the heads.
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And O and X heads as well.
My Galen book says 68-71 were X (2.02/1.60)
70-71 360 were J,Z, or O (1.88/1.60)
70 TA were U or O (2.02/1.60)
72 340-360 were J (1.88/1.60) I would imagine the 73 and 74 were J's as well although they were listed as a different casting number. (3671587)
There was also a 894 head with a Z. I had a U and an X Drivers side was the U.
Locomotion
Well-Known Member
I saw the question asked many years ago but don't recall the answer - "What did the different letters mean and were they casting # specific?" I don't normally use the letters as a reference, just the casting #'s because it gets confusing. Anybody have any additional info?
'68-'70 340 = 894
'70-'71 (-'72) 360 = 915
'70 T/A = 915
('71-) '72 340 = 915
'73-'74 340 & 360 = 587
As far as I know, only the 894 X head had "340" cast into it while the rest had "360".
I borrowed these pics from another members post a long time ago. I believe the story was that these original bare X 894 castings were machined with T/A intake pushrod locations by Mopar during development before 915's were available. Only 915's were eventually used on T/A & AAR production cars.
Galens book is wrong. The chances of a 71 model year engine have an X head on it are so small. As though there was a dusty set laying around.
915's were the baseline/intended production head for the 1970-72 model year on 340's. Anything 1970 with an X head was a carry over of prior year inventory.
915's were the baseline/intended production head for the 1970-72 model year on 340's. Anything 1970 with an X head was a carry over of prior year inventory.
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Dartswinger70
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340? I like 340... 
moparsareforme
New Member
Yes you are correct Galen is wrong. I have a 70 TA 340 that has U heads, I have seen some other mistakes also. I have O U D J heads that are stock 1.88 and 2.02
That's a first for me and pictures don't lie.
340's were 10.5-1 compression with 894 heads. In 1970 when they put the 915's on with the same piston and cam. Then the compression dropped to 10.3 in all service manuals for 1971. All the small valve 340's were 8.5-1 this drop was with the pistons use
so my o heads with 202 are ta heads ?...is that good or bad for my 69 340 build
Only if they have factory offset pushrod holes in them.
See the pics above where the holes are on those 894 heads. See the flat area and dimples in the intake runner walls, that is where the std pushrod holes are located.
theses are mine i guess thats 915
so ta had solid cam ?
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Any 915 casting head could be ground out to be a TA head.
Never heard of a 915 head O, U, J, being cast early enough to be used prior to 1970.
What exactly are you saying?
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