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Getting my 516 heads done.

Got an update.. He said he had to take 20 thousands off the surface to clean them up. Also he is matching the intake side to keep them squared up. Tomorrow he is stopping by to check my block sag. So I will know more about that tomorrow. He also told me the heads already had hardened seats intake and exhaust. So thats good I guess.
Still going to 1.74?
 
Ok by using a straight edge I can get a .021 and a .019 together under the straight edge with a little drag at TDC So the measurement is 0.04 piston height at the deck. Does that sound correct? I also went back with the straight edge and checked the block sag and Im not so sure its sagging now but its hard to tell because of the aluminum level is not rigid enough to swear by the measurements.
 
Ok by using a straight edge I can get a .021 and a .019 together under the straight edge with a little drag at TDC So the measurement is 0.04 piston height at the deck. Does that sound correct? I also went back with the straight edge and checked the block sag and Im not so sure its sagging now but its hard to tell because of the aluminum level is not rigid enough to swear by the measurements.
Actually the aluminum level may be off more than the block. My 2 cents.
 
Actually the aluminum level may be off more than the block. My 2 cents.
Thats what I was thinking too it flexes too much to get an accurate measurement. However it was across the cylinder and I believe that 0.04 is an accurate measurement. I just don't trust the span of the block across the head.
 
Well the block needs to be decked.. So I have to take it apart so I can get it fixed. Also needs to be honed but hopefully I wont have to buy new pistons.. I watched him use his straight edge and feelers got some sag spots that were 7 thousandths low. So its decking time. Also Hes saying with the combo Im going to be running I'll be close to 11 to 1 with 039 gaskets. Assuming the heads are at about 65 to 70 cc. He said he will check the CC's after he gets the valves in the heads.
 
Well the block needs to be decked.. So I have to take it apart so I can get it fixed. Also needs to be honed but hopefully I wont have to buy new pistons.. I watched him use his straight edge and feelers got some sag spots that were 7 thousandths low. So its decking time. Also Hes saying with the combo Im going to be running I'll be close to 11 to 1 with 039 gaskets. Assuming the heads are at about 65 to 70 cc. He said he will check the CC's after he gets the valves in the heads.
Hopefully it won't be quite that high, but it will be the machine work that puts it there. It also tells me that it was originally a 10:1 engine. I just didn't realize that the pistons on the 66-67 383's were down in the hole. Originally when I saw that they were in the hole, I thought 9:1 2bbl. engine.
 
Also Hes saying with the combo Im going to be running I'll be close to 11 to 1 with 039 gaskets. Assuming the heads are at about 65 to 70 cc. He said he will check the CC's after he gets the valves in the heads.

Add 10-15 cc's to that...

According to the calculator on the Diamond Piston website .040 in the hole, 80cc chamber & an .039 gasket puts you at 8.8. Change to a steel shim head gasket & you get 9.16
 
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Some info I found on the web.. Now this doesn't take in account of a 2bbl engine. But the standard 4bbl 300hp was 10:1 I cant imagine any changes to the CR with a 2bbl intake. I thought the HP ratings were 300 HP and 325 HP In later years the CR was reduced post 70's

1966-1967
4-bbl
325@4800 rpm
425@2800 rpm
10:1

1968-1969 sc
4-bbl
330@5000 rpm
425@3200 rpm
10:1
1968-1969 hp
4-bbl (Carter AVS)
335@5200 rpm
425@3400 rpm
10:1
1970
2-bbl
290@4400 rpm
n/a
8.7:1
1970
4-bbl
330@5000 rpm
425@3200 rpm
9.5:1
1970
4-bbl (Holley)
335@5200 rpm
425@3400 rpm
9.5:1
1971
2-bbl
275@4400 rpm
375@2800 rpm
8.5:1
1971
4-bbl
300 rpm
410@3400 rpm
8.5:1
 
Those are advertised numbers, they aren't real.... Advertising is allot like politicians... They lie allot.....
 
Here is another and they dont list a 2bbl option here either for 1967. Only the 4bbl
V8-383 4-bbl 4.25 x 3.375 10:1 325 @ 4800 425 @ 2800 45-65

Here is the 66 383 2bbl which is closer to the lower CR
V8-383 2-bbl 4.25 x 3.375 9.2:1 270 @ 4400 390 @ 2800 45-65

And the 66 4bbl version.
V8-383 4-bbl 4.25 x 3.375 10.0:1 325 @ 4800 425 @ 2800 45-65
 
Some info I found on the web.. Now this doesn't take in account of a 2bbl engine. But the standard 4bbl 300hp was 10:1 I cant imagine any changes to the CR with a 2bbl intake. I thought the HP ratings were 300 HP and 325 HP In later years the CR was reduced post 70's

1966-1967
4-bbl
325@4800 rpm
425@2800 rpm
10:1

1968-1969 sc
4-bbl
330@5000 rpm
425@3200 rpm
10:1
1968-1969 hp
4-bbl (Carter AVS)
335@5200 rpm
425@3400 rpm
10:1
1970
2-bbl
290@4400 rpm
n/a
8.7:1
1970
4-bbl
330@5000 rpm
425@3200 rpm
9.5:1
1970
4-bbl (Holley)
335@5200 rpm
425@3400 rpm
9.5:1
1971
2-bbl
275@4400 rpm
375@2800 rpm
8.5:1
1971
4-bbl
300 rpm
410@3400 rpm
8.5:1
Don't hold me to it, as I'm going on memory, but the 67 383 2bbl engine was 280 HP due to the carburetor and lower compression ratio. I will have to go to the service manual for clarity. The 4bbl specifications you posted are dead on.
 
Here is another and they dont list a 2bbl option here either for 1967. Only the 4bbl
V8-383 4-bbl 4.25 x 3.375 10:1 325 @ 4800 425 @ 2800 45-65

Here is the 66 383 2bbl which is closer to the lower CR
V8-383 2-bbl 4.25 x 3.375 9.2:1 270 @ 4400 390 @ 2800 45-65

And the 66 4bbl version.
V8-383 4-bbl 4.25 x 3.375 10.0:1 325 @ 4800 425 @ 2800 45-65
I think the 66 2bbl specs will be the same for 67.
 
So I guess this raises the question why they dont even show a 2bbl option for 1967? They only show a 4bbl option. In 1966 Yes both are shown but not 67.

1966 right from the page..
V8-383 2-bbl 4.25 x 3.375 9.2:1 270 @ 4400 390 @ 2800 45-65
V8-383 4-bbl 4.25 x 3.375 10.0:1 325 @ 4800 425 @ 2800 45-65

1967 right from the page.
They didn't offer a 383 with a 2bbl. I assume the 2bbl option was the 361 or maybe its a typo and should have been a 383 at 270 HP. Which is likely the issue..
V8-361 2-bbl 4.25 x 3.375 9.2:1 270 @ 4400 390 @ 2800 45-65
V8-383 4-bbl 4.25 x 3.375 10:1 325 @ 4800 425 @ 2800 45-65
 
Anyhow he said the deck on one side was ok the deck on the other side was out of whack. So I'll get it square decked and call it good. Already have the heads almost done and may have them back later today or tomorrow. Either way Im ok with the engine its not going to be a race car just something fun.. even if it is 8 to 1 lol. I just have fun messing with this stuff. Its not a job or a must do I just like trying to figure it all out... I guess that's the point of the hobby anyhow.. Learning and having fun doing it. Otherwise it would be boring and mundane kind of like my normal job.
 
I don't remember a 361 being offered in 67. In 66 yes. In 67 it was a 383 4bbl or 2bbl. In 66 it was a 383 4bbl or a 361 2bbl. I may be wrong for thinking and have sometimes been.
 
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