I have a set of 243's heads that came from a Corvette (sodium filled heads) but valves were lost. Can I use regular valves from another regular cast LS1 heads? Same size, same length between the sodium filled and the regular ones?

 

You could use the valves from a 799 head but won't be sodium filled.

 

What about other LS1 heads valves; from 241's or others?

 

Valves are different length in the LS6. It's .050" longer.

 

How is that possible? Don't they use the same pushrods?

 

yes they do but the cam has a smaller base circle in an ls6

 

Having the 243's with sodium filled valves and the LS6 cam, what's the size (lenght) of push rods needed?

 

While you've got the heads off will you be changing lifters? Strongly consider this if you plan to run heavier than stock springs.

 

I have new LS7 lifters.

 

0.0236"...................

 

New, yellow springs tat comes with the LS6 cams. Which push rod length I will need?

 

7.400 should work but you should measure to be sure