trickability

Anyone had a exh valve break. Have heard or this and am changing to stainless exh valves for peace of mind

1stZ

I switch to stainless Steele as well. I also know a number of guys that switch to stainless Steele eventhough their exhaust valve were fine. That said, I'm not so sure it is that much better (if better at all?!?) than the sodium field stock valves.

NOSZ06

I think Katech answered this several months ago. Stock valves in general were OK.

dfinke23

The main advantage is that they will bend and not break under extreme circumstances (piston/valve contact).

1stZ

That's what my mechanic told me theoretically. But the end result will be the same. The stock stainless steal exhaust valve, sodium field & hollow stem is better performance wise cause of its lighter construction and with the sodium keeps it from heating up too much. But with the sodium filling it, it has a hollow stem which is not as strong as the solid stainless Steel valve. Thus the snapping. The solid stainless on the other hand is heavier & stronger but heats up more & could seize up and in turn could cause the same damage as a snap valve would. Who knows which is better? All I know is that sodium filled exhaust valve or stock valve was good to me until after we install the cam & double springs. IMHO, the upgraded springs were too strong for the stock valves. My .02. Who knows which one is better?

Katech_Zach

Do you have a stock cam?

J HEBERT

Valve control (or loss there-of) coupled w/ high spring pressures will break the head off the stock valve. When u switch camshafts and select a dyno-queen grind that is very aggressive, and then over-rev the thing u are just begging for it to happen. Stainless valves are stronger, and when u violate the space-time continuum (piston/valve contact) they tend to bend rather than break. They are significantly heavier than sodium filled. Way heavier than titanium. Now we're talking loss of valve control w/ radical lobes w/ heavier valve-train. U see where this is going? If u knew the rpm that the valvetrain went unstable and stayed a couple-hundred rpm below that (hopefully its well past peak power) a few engine blocks would still be intact. I have seen an alarming # of failed valves in stock caddy 6.2L motors. Walk into a couple dealer service depts. and u can't swing a dead cat w/o hitting one.