Educate me please !!! LA info needed

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I found a head chart in the Larry Shepard "How to hot rod small block Mopar engines" book. All 273 heads up to and including 1967 had closed chambers in the 57-64.5cc range. 68-69 and 318 heads to 71 had a open chamber in the 60-67.5cc range. And the list goes on and on. Those heads have the 1.78/1.50 valve sizes.
 
Marine/industrial cylinder head with symmetrical exhaust ports and most likely 675 type small ports. With quench pads, reported to measure close to 58cc's as cast.
 
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toolmanmike said:
I found a head chart in the Larry Shepard "How to hot rod small block Mopar engines" book. All 273 heads up to and including 1967 had closed chambers in the 57-64.5cc range. 68-69 and 318 heads to 71 had a open chamber in the 60-67.5cc range. And the list goes on and on. Those heads have the 1.78/1.50 valve sizes.
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Ok thank u
Yes a member mentioned in older thread the 234 - has the 57 cc
Chambers .
 
toolmanmike said:
I had to mill mine down .030 to get to 57 cc.
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Ten 4
Thank u these will be stored / preserved !!!
U are correct only way to know is to cc them !
I cherish them though since they are kinda rare these days .
Im running alum heads on current project.

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Good idea. I think I'll bookmark my post as well so I won't have to look up the specs again. :thankyou::thumbsup:
 
Curiosity got the better of me. Measured this set of 234's and got 67.5cc, yes the seated surface (sunk) indicates multiple valve jobs. Even checked it again with different equipment. as is it's 67.5. The block, here's another 318 with the machine marks.
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Dana67Dart said:
In the photo in post 1 of the block the slots look deeper on the left then the right, would that have been due to casting creep ( or whatever it's called)
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Casting core shift..Thats why you check deck height on block for race. Because we had Quality spec that were not real tight for stock
 
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SGBARRACUDA said:
So was this something done after a certain year? Or just by a certain block plant? I've never seen it on a factory built engine. The engine Chris is talking about was as built when new, Bearings were dated 2-72 so it is a virgin engine.
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Not certain Years it was the type of Multi heads machine and tooling they used if it was adjustable cutters or standard they needed clearance for them when they machined them
 
The valley casting contour looks different on Chris’s block in the first pic. It looks more like the’75 model 360 block I have than most 318s I have seen. It looks like the valley is narrower up top and the upper half of the cylinder is bulged some amount for larger water jackets.
 
SGBARRACUDA said:
So was this something done after a certain year? Or just by a certain block plant? I've never seen it on a factory built engine. The engine Chris is talking about was as built when new, Bearings were dated 2-72 so it is a virgin engine.
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Not after certain year just the type of boring heads used ..Its for machining clearance ..Thats like all the square blocks by the bell housing in back of block and the dowel holes .They were used to clamp block during Machining process
 
SGBARRACUDA said:
So was this something done after a certain year? Or just by a certain block plant? I've never seen it on a factory built engine. The engine Chris is talking about was as built when new, Bearings were dated 2-72 so it is a virgin engine.
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SGBARRACUDA said:
So was this something done after a certain year? Or just by a certain block plant? I've never seen it on a factory built engine. The engine Chris is talking about was as built when new, Bearings were dated 2-72 so it is a virgin engine.
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1Badcolt said:
Ok thank you
This is a 72 model block
I have a 68 - 70 - (2) 74 model blocks all trucks blocks like this one and none have this machining so was just curious.
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were they 360 or 318 blocks cuz you have to remember lager bore more meat on block around bore
 
Garrett Ellison said:
The valley casting contour looks different on Chris’s block in the first pic. It looks more like the’75 model 360 block I have than most 318s I have seen. It looks like the valley is narrower up top and the upper half of the cylinder is bulged some amount for larger water jackets.
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Thank you for info
 
Max; Thanks for the pics. Never saw the heart shaped chambers before, or saw 'truck' cast into the cyl. head. Not much use for them on the street without a water heated manifold in cold country. That said, they might be desirable for NHRA stock classes [no exhaust passageway for manifold heat = better port flow].
 
1Badcolt said:
Thank u for the info
Is that a industrial 318 block or just ?
Also does it have truck or car style mounts on block ?
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Block date is 7 13 72, info on front is JM318R 4023066, Pad by pan rail reads 3B100142, block has 4 engine mount ears per side
 
Another LA with no ribs between lifters necessitating V-link bars. You could get away with straight bars with no 360 rib. You can use those heads on a car no problem. I've never heard of any stock 273 heads being anywhere near their 'blue print' 57cc, also explains why the '10.5:1 Commandos' never measure that high.
 
pishta said:
Another LA with no ribs between lifters necessitating V-link bars. You could get away with straight bars with no 360 rib. You can use those heads on a car no problem. I've never heard of any stock 273 heads being anywhere near their 'blue print' 57cc, also explains why the '10.5:1 Commandos' never measure that high.
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Agreed. I had to mill my 273 heads to come close to the minimum.
 
pishta said:
Another LA with no ribs between lifters necessitating V-link bars. You could get away with straight bars with no 360 rib. You can use those heads on a car no problem. I've never heard of any stock 273 heads being anywhere near their 'blue print' 57cc, also explains why the '10.5:1 Commandos' never measure that high.
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57.3cc in NHRA minimum spec. It takes a .040" cut to get there.
 
Max1196 said:
Block date is 7 13 72, info on front is JM318R 4023066, Pad by pan rail reads 3B100142, block has 4 engine mount ears per side
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The 'J' means model year 1973. The pan rail '3B100' could mean it came from a 1973 B100 van?
 
pt70 said:
Max; Thanks for the pics. Never saw the heart shaped chambers before, or saw 'truck' cast into the cyl. head. Not much use for them on the street without a water heated manifold in cold country. That said, they might be desirable for NHRA stock classes [no exhaust passageway for manifold heat = better port flow].
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Im going to check my heads where was located on heads ?
Thanks Chris
 
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