63?? 327 swirl polished valves

[Joe L.]

Re: 63?? 327 swirl polished valves

All-----


I was unaware that the swirl-polished valves were used prior to 1964. However, based on several responses to the contrary here, I did some further checking and it appears that some were as far back as 1957. This would include some 1.72" intake valves and some or all 1.94" intake valves. I haven't confirmed it for the 1.50" exhaust valves but it appears that some were swirl polished, also. I'm going to do some more checking and, hopefully, dig out some examples for empirical information.

[Duke W.]

Re: 63?? 327 swirl polished valves

My 9-80 P&A catalog calls out 3774695 inlet valve for '57-'60 "w H. L. cam", which was the Duntov cam. Other engines used a different valve. Both valves are the same dimension, so the difference might be that fact that the ...695 was finished on the backside.

A "special" exhaust valve is also specified for all '56-'63 w/ H. L. cam and I believe this valve has a "Silchome #1 hardened tip, which differentiates it from the other 1.5" exhaust valves used with hydraulic lifter camshafts that do not have a hardened tip welded on.

Duke

[Clem Z.]

Re: 63?? 327 swirl polished valves

also the material removed under the valve head by the "swirl polish" would also remove a few grams of weight from the valve allowing a few more max RPMs before valve float