I need to figure out my compression ratio so I can continue to putting the engine back together.

Here is what I got so far:
327 SBC 0.030" over
Bore = 4.030"
Stroke = 3.25 (didnt measure used info from web! Bad idea?)
Felpro Gasket diameter = 4.125"
Felpro Gasket Thickness = 0.039"
Deck Clearance = Unknown, slightly below deck.
Combustion Chamber = World Head 64 or 75. (How do I know which?)
Pistons are dished and stamped (L2165 030) CAN ANYONE TELL WHERE I CAN FIND THAT VALUE?

I'm using the below link to calculate compression so I can pursue what CAM I'm going to go with.

http://www.csgnetwork.com/compcalc.html

 

Kinda late to worry about compression after you got all the parts. The only accurate way of measuring is to actually measure the volume of the combustion chamber, and the volume from the top of the piston to the top of the block when the piston is a TDC. Then plug that into your formula.

 

I played with the numbers on Desktop Dyno, but there are still a few variables that you need to answer.
How much of a dish do the pistons have?
How far down the bore is the top of the piston at TDC, use a straight edge and a feeler gauge.
Which chamber heads do you really have? Did you buy them? If so, you should have that info, or at least a part number to look up the specs.
With 64 cc heads, and flat top pistons, c.r. would be in the range of 9.85.
With 75 cc heads, and flat top pistons, c.r. would be in the range of 8.74.
Factoring in dished pistons instead will lower the above c.r. numbers. And changing the down bore measurement (depending on what you have) will either raise or lower the c.r. The unknowns need to be known to get a more accurate ballpark figure.

 

Dish on piston: Need help cant find. Pistons are L2165 with 4 reliefs in them.

Deck to top of piston at TDC = 0.025" from deck to piston at tdc = 0.3188 cu in.

Inherited heads when I bought the car. World doesnt specify how to ID the chamber size. Need to call CS only open 11-1, weird hours. They tell you everything else on their site except how to ID the chamber size.

Couple other questions my gasket is a felpro and spec says .039 thick, is that the compressed thickness or out of box?

Does higher compression = higher performance?

 

Dish on piston: I think you might be describing flat tops with valve reliefs? Dished pistons drop down, and the top actually looks like....a....dish!
I just happen to have a new/old sbc .030 stock replacement piston sitting around. It's for a 1980's (low compression) vintage engine. You can see it has both a dish, and 4 valve reliefs. Do yours look like this, or are they flat top with the reliefs?
And yes, higher compression means higher performance. And the higher you go will also mean higher fuel costs for having to use premium, or an octane booster.

 

It's just the 4 relief valves!