I bought a 243 heads the seller told me it's from his vette 2002 ZO6. Upon research 20-04 Zo6 heads have sodium filled and hollow valves. I removed one exhaust valve and weighed the valve from a scale i bought from Harbor Freight(looks like Harbor Freight scale is not accurate).
The scale is 5oz over the weight, I weighted 12oz can of coke it scale says 17oz so it's 5 oz over. Upon weighing the valve deducted 5 oz(converted oz to grams) from the weight it came to 70.87 grams.
1) So this valves is not sodium filled valves?

2) see photo of the valve seal. Should I replace all the valve seals? can i leave the seals? This heads came off 02 zo6 had 37k miles.

3) is this the spring on the heads the ones that have problems? should I replace the springs? is yes can i reuse the springs from my 97 c5 heads? or should I replace springs with dual coil springs?

4)the cylinder deck around the valves was build up with some carbon, the seller took it off i'm guessing by da'ing it ,you can see the grind marks. Is it ok for me to install the way it is ?

5) What do i need to do to the heads or get checked for before I install? and how much to expect for the cost if sent out to shop?

6) Is it worth to get the heads ported? How much more HP can I expect from porting and how much is cost to porting?

So far I have 243 heads, LS6 intake, Zo6 air cleaner coming, zo6 titanium muffler for my mods.
I'm looking into getting 400 rwhp. Looking into getting a cam that is not aggresive still want to maintain driveability.
what else do i need to reach my goal? As always I have a budget -not open wallet.

 

The valve seals are so easy to change, yes, you should replace them.

And you will want to replace those springs no matter what ones they are if you are putting in a cam. They will not handle the lift and then you'll have real troubles.


Can't speak to the valves, but do note that a 12oz can of coke does not weigh 12oz. It's 12 FLUID ounces of liquid. Not 12oz by weight. https://www.reference.com/science/mu...308674742d878a

 

here's photo of the vale on the weight scale. I don't think this scale is accurate????

 

That actually is about right. Sodium valves are ~62-66 grams. Stock exhaust valves are ~85-88 grams.

Either way, I wouldn't lose sleep over it.

 

I have a used set of pac 1518 springs and a new set of viton valve seals if you are interested in replacing that stuff... on the scale, I believe sodas are by volume and not weight so your scale might have been pretty close to begin with