Does a stock 330 have dual valve springs? Mine has the outer spring plus an inner spring like the ones sold at Comp Cams:

 

Yes that's a spring and a dampener not a dual spring.

 

Okay, thanks, sounds like an expensive option in 1967, so I was wondering. It had me confused, my old Ford 289 had a single spring.

 

As noted, the flat inner "spring" is actually a damper that prevents spring harmonics.

 

Is that 'Joe Speak' for valve clatter?

 

Olds did have an inner spring, 393649 for 65-66 V8 H.D. "Note: This part used to provide supplemental spring loads at extreme high speed shifts. Intake and exhaust valve oil deflectors must be removed and discarded when installing this spring."