340 heads

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udlooz

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Can someone identify the type heads from these pics?

20171209_164440.jpg


20171209_164431.jpg
 
That's a small block Mopar head...

But seriously, pull the valve cover and look on the ports under the rocker shafts for a casting number and we can tell you more...
 
be easier if you removed the 1st two plug wires and took a better pic of the spark plugs or take the valve cover off and get a casting #
 
Are there two vertical lines between the spark plugs? Look like 73 340 heads. Pull a valve cover and get the casting number. Its the only sure way to know what you have.
 
X factory 2.02 valves, open chamber
 
Yes, well maybe this X calls for some more explanation.
It is not that the X means you can use them on any engine… The X refers to, as seen in this picture below, the X in the casting.
The X-head was found only in 1968 and 69 on the Mopar 340 engine. Some early 1970 engines had them too as I understand it, but I can´t verify this out of my own experience. They are considered to be the best head Mopar ever offered on a small block engine from the factory.

20171217_111500 my Xheads.jpg
 
I have an old 70 cuda' it has X heads on it, I know that the heads have not been off the motor.
 
More likely a 340 x head, but call me crazy if ya want... I have seen some late 60's 318 heads that had an x on them...i was all excited in my 20's when I found the set only to find 1.78/1.50 valves.
 
You need the casting number to be sure.
 
MOPAROFFICIAL said:
More likely a 340 x head, but call me crazy if ya want... I have seen some late 60's 318 heads that had an x on them...i was all excited in my 20's when I found the set only to find 1.78/1.50 valves.
Click to expand...

:) yes Ma Mopar... remember the cast#:s?
 
I bought a set of "J" heads off a 1971 police cruiser that had 2.02 valves in it, 360 motor.
Junkyard score 30 yrs ago.
 
I have also seen J heads with factory 2.02's. Sure they could have been added but a couple appeared to be virgin motors. No way to know for sure.
 
The ones I had were off a county cruiser, no reason to doubt they did come on the car, sitting right beside it was a 69 GTO he was chasing.
Big newspaper story at the time.
My buddy bought the motor out out of the goat, ram air something motor.
 
Well to me it´s not likely there are two different X-head castings, we surly should have heard about that. Not that I have heard everything about SB Heads, but still... Since the 1.78/1.50” valves was a 273/318 thing, maybe Chrysler took what was available when they ran out of heads, and simply machined some 894 X-castings (´68 340 ) to fit the smaller valves, till new castings were ready to use.
I hope someone can straighten this out with casting #:s. Till than I somewhat provocative claim this is what happened...
 
As far as small blocks are concerned, this appears to be a fairly accurate listing. I believe around 1970 340's were 915 w/2.02's.
The 308 head was used from the late '80's till the last 360 LA around '92? Don't know what was used through the rest of the '80's.

Small Block Mopar Cylinder Head Casting Numbers | Hot Rod Reference

Earlier heads had the casting numbers under the valve cover. At some point, later heads had them visible from the chamber side of the head.
 
Ooooh, I got me a set of X heads! Whoop-de-damn-do!

One more time.

Any head that came from the factory with 2.02 valves is already screwed up and will never be as good a set of something like J heads starting with 1.88 valves that you put in 2.02 valves and do the throats correctly.

Dad said, "Ya gotta be smarter than your cylinder heads!"
 
Locomotion said:
As far as small blocks are concerned, this appears to be a fairly accurate listing. I believe around 1970 340's were 915 w/2.02's.
The 308 head was used from the late '80's till the last 360 LA around '92? Don't know what was used through the rest of the '80's.

Small Block Mopar Cylinder Head Casting Numbers | Hot Rod Reference

Earlier heads had the casting numbers under the valve cover. At some point, later heads had them visible from the chamber side of the head.
Click to expand...

Yes, this is what I go with also when bench racing.´70-72 J-heads (915) in different configurations.
Now, there are only six different SB-head casting number from ´64 till late sixties, (1.78X1.50" and 2.02X1.60 valves) when MOPAROFFCIAL noticed this X-heads (witch I absolutely believe is a correct description), and which one would be an X-head other than the 894?
I´m sure there are guys here who know their early SB-heads and #:s and can step forward.
What I´m trying to get at is, there but one X-head casting... the 894.
Anything else is yet another example of, how Ma-Mopar quickly solved a problem that showed up on the assembly line...
 
IQ52 said:
Ooooh, I got me a set of X heads! Whoop-de-damn-do!

One more time.

Any head that came from the factory with 2.02 valves is already screwed up and will never be as good a set of something like J heads starting with 1.88 valves that you put in 2.02 valves and do the throats correctly.

Dad said, "Ya gotta be smarter than your cylinder heads!"
Click to expand...

Do you happen to know anything about an X-head with 1.78X1.50 valves?
 
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