thunder550

iTrader: (70)

Talked to a shop that told me I need to replace the exhaust valves if I am going to be running a 408 with 15psi. True or not true?

kbracing96

iTrader: (26)

What was there reason for this?

thunder550

iTrader: (70)

1500* egt's, according to them, burnt valves

1slow01Z71

iTrader: (36)

When youput the turbo on, get Richard at WCCH to a clena up job on the heads and throw some bigger ss valves.

kbracing96

iTrader: (26)

IDK, look how long parish ran stock 317's on his 408.

1slow01Z71

iTrader: (36)

A high HP nitrous motor will put more heat on the valves then a turbo will and I know personally of a guy in Houston running a 408 with stock 241 heads and a 250 shot without a problem thus far. The problem you are going to run into with sotck heads and high HP is head lifting since the deck is relatively thin. ARP head studs over tq'ed 10-15#s and cometics will help alot but not totally. 15#s is going to be on teh edge with ARPs and cometics.

thunder550

iTrader: (70)

OK so it sounds like the stock valves will be fine. I'll worry about the head lifting problem when the time comes......hopefully it won't be an issue.

1slow01Z71

iTrader: (36)

Buy head studs to start with and cometic head gaskets dont waste your omney on anything else

I wasted my money on ARP head bolts. Richard fomr WCCH has the 12 point head studs for 230 best price I have found yet(FYI)

thunder550

iTrader: (70)

Ok, thanks for the info. Why is there a difference in bolt and stud strength?

1slow01Z71

iTrader: (36)

Difference in clamping force. You can over tq the head studs a bit to help out with the head lifting problem.