John,
Its good to know that you have found some stronger parts and have learned from the expiriance of boosting your m44. I am surpirsed to see that a valve failed. How did the valve fail from heat? Normally I have only seen a valve fail due to exessive forces from an aggressive cam, poor timing or an over rev. I would agree that the busa spring would be made at a higher quality as they have to handle the rpm and hard work that a race engine does. I guess with the ARP stuff its just a fail safe and something that you just wouldnt have to worry about.
I didnt think you were bashing, as there are people on forums that give advise on things that other people have just told them but never seen or tried and that does really help. So its good to question peoples answer to find out if they are full of S#@T
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