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Limitations of stock valves

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Old Nov 17, 2006 | 06:31 PM
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Default Limitations of stock valves

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?
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Old Nov 17, 2006 | 06:36 PM
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What was there reason for this?
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Old Nov 17, 2006 | 06:41 PM
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1500* egt's, according to them, burnt valves
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Old Nov 17, 2006 | 06:46 PM
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When youput the turbo on, get Richard at WCCH to a clena up job on the heads and throw some bigger ss valves.
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Old Nov 17, 2006 | 06:59 PM
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IDK, look how long parish ran stock 317's on his 408.
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Old Nov 17, 2006 | 07:01 PM
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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.
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Old Nov 17, 2006 | 07:11 PM
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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.
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Old Nov 17, 2006 | 07:15 PM
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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)
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Old Nov 17, 2006 | 07:16 PM
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Ok, thanks for the info. Why is there a difference in bolt and stud strength?
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Old Nov 17, 2006 | 07:18 PM
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Difference in clamping force. You can over tq the head studs a bit to help out with the head lifting problem.
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