I think more than anything its a numbers game! I know for a fact that Offenhauser wont make a run of their V8-60 Flathead heads until they get over 80 sets spoken for. A good friend of mine that manufactures and sells a V8-60 powered motorcycle,is extremely close and tight with Vic Edelbrock,and Vic has even stayed at my friends house on several occassions for business related travels, told my friend that he wouldn't even offer the V8-60 head to him for less than 250 sets. Vic told him that the last time they made a run of those heads was in 1960 or 61. So,I suspect that have that same mind set even for smaller stuff like intakes and valve covers....you'd think they would try to supply the market as there is sufficient demand for it!
