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Getting my 516 heads done.

BeepBeepRR

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Finally getting my 516 heads done. New valve springs, new 1.74 exhaust valves and bowl work. As well as cleaned and surfaced.. Next I will be tearing the 383 down to have it honed and decked. I ended up swapping out some heads and cash to get the heads done. I love the horse trading...saved me a ton of cash. Next I gotta come up with a horse trade for the machine work on the block..
 
Finally getting my 516 heads done. New valve springs, new 1.74 exhaust valves and bowl work. As well as cleaned and surfaced.. Next I will be tearing the 383 down to have it honed and decked. I ended up swapping out some heads and cash to get the heads done. I love the horse trading...saved me a ton of cash. Next I gotta come up with a horse trade for the machine work on the block..
How much are you going to deck the block?
 
Just enough to get the sag out of it. The center web is about .004 lower than the ends. Probably would be alright with a thicker 039 head gasket but why chance it. Going to use the Summit K6401 cam and lifters in the 383. Thats the same cam I put in my 440. I may end up putting a roadrunner cam in instead. Havent purchased one yet so that is still up in the air. I want a little rumble but want to be able to use pump gas.. Although I was reading the 67 383 was already 10 to 1 even with the pistons in the hole.
 
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Are you using stock, or new pistons?
I ask because some of the 67-69 383's stock piston sticks above the deck at TDC.
I have read some issues using those engines and 516 heads with large camshafts.
You may already be aware of this.

I can give you a link to the information if you are interested.
 
:xscuseless: LOL Post some pics when you can. We love to see some cylinder head ****!
 
I may have mis-spoken, in above post
A quick look in some of my books, and the issue is MAINLY using 67 heads on 68-69 383 engines. (they have the positive deck height)
Or if you mill the heads or block on a 1967 383 AND add larger cam, you may required valve notches.

Just passing along info.
 
The pistons are below deck so I don't think there will be any clearance issues. They are 30 over pistons but seem to be stock replacements. Just getting the heads cleaned up and surfaced. Not doing anything to reduce the deck height other than the surfacing. Just a surface, springs and exhaust valve change. The block also needs the sag taken out. I don't think the amount that needs to be removed will be that huge.

Bad B..
Yea the K6401 cam isn't that radical. Its actually used fairly often on low compression engines. Lets say for instance a 77 Motorhome 440.

Duration at 050 inch Lift: 224 int./234 exh. Advertised Duration: 298 int./303 exh. Intake Valve Lift with Factory Rocker Arm Ratio: 0.466 in. Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.488 in.

These are the pistons that are in the engine.
https://www.summitracing.com/parts/slp-366np

Brand:Sealed Power

Manufacturer's Part Number:366NP

Part Type:Pistons

Product Line:Sealed Power Cast Pistons

Summit Racing Part Number:SLP-366NP


UPC:724956347360

Piston Rings Included:No

Bore (in):4.250 in.

Bore (mm):107.950mm

Stroke:3.750 in.

Rod Length:6.358 in.

Piston Style:Flat top, with no valve reliefs

Piston Material:Cast aluminum

Compression Height (in):1.848 in.

Piston Head Volume (cc):0.00cc

Wrist Pin Style:press-fit

Wrist Pin Retainers Included:No

Wrist Pin Included:Yes

Pin Diameter (in):1.094 in.

Piston Ring Thickness:5/64 in. x 5/64 in. x 3/16 in.

File Fit:No

Gapless:No

Quantity:Sold as a set of 8.

In-Store Pickup:Choose In-store pick-up (OH, NV, GA, TX) on our web site.

CalculatorCompression Calculator

ToolStroker Combinations
 
:xscuseless: LOL Post some pics when you can. We love to see some cylinder head ****!

Well since BeepBeepRR doesn't have any pictures ready how about these?


IMG_5179.jpg
IMG_5142.jpg
 
Here is how far they are in the hole. Not way down but they are down. I don't have a bunch of tools for measuring this stuff.

This is cyl 3 at TDC.
IMG_3519[1].JPG

Cyl 2
IMG_3520[1].JPG
 
I do have feeler gauges but the only straight edge I have is a 4 foot aluminum level lol.

Here is the block sag with the 4 foot level. Note... After looking at it again it doesn't seem as bad as I thought.

IMG_3521[1].JPG IMG_3522[1].JPG
 
Not by much. Can you say quench? Not a bad idea to have the combustion pushing on the whole piston! LOL
Was thinking a steel shim head gasket.. But May end up with the 39's really depends on how much he has to take off the heads.. I honestly think they were in good shape to start with. I just wanted the valves changed and new springs. I just don't want the valves to push the piston down lol...
 
Here are the 516's when they came off.. Kind of crappy pictures but I was looking at the size of the valve springs more than the heads..

IMG_3433.JPG IMG_3434.JPG IMG_3435.JPG
 
I do have feeler gauges but the only straight edge I have is a 4 foot aluminum level lol.

Here is the block sag with the 4 foot level. Note... After looking at it again it doesn't seem as bad as I thought.

View attachment 969321 View attachment 969322


That 4 foot level will work, hold down on the straight edge while trying to slip feeler gauges between the straight edge & the piston top.... You can get a pretty accurate number that way....
 
BeepBeepRR, sounds like you got a good handle on things!!!


Here is a shot of a 69 383 at TDC, (sorry its blurry)


223.gif
 
Just a funny note: the quoted specs from summit is wrong (clearly) otherwise if they were correct, that piston would be out of the hole almost an eighth of an inch. (Specs say for a 3.75"stroke)
If fixed for a correct 3.38 stroke, that piston would be .084 in the hole, at blueprint spec
It doesn't look that far down to me in your pics, but previous suggestions to use a straightedge and feeler gauges is a good idea. Actual measurement is always better than educated guess.
And I would for sure use the steel shim, unless that pushes compression too high (unlikely).
 
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.020 down in the hole, .020 steel shim gasket....perfect! Just make sure you have proper V/P clearance.
 
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.
 
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