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boxman
08-23-2001, 10:30 AM
I was looking at the Rod and Custom articals, and have a question for other nailheaders. Has anyone used Chevy valves, springs, and retainers on there nailhead. How did you account for the smaller valve stem( Chevy 11/32, .34375 Vs. the .3720 of the Buick)? Are new valve guides able to make up the difference? Stock spring pressure is 101 lbs @ 1.16". The lowest spring pressure that I can find for a Chevy is a single spring with 280 lbs @ 1.187". Will a cam survive pressure like this? Will the stock head this kind of pounding? Will I have to go to hardend valve seats? Will the lifters even be able to pump up? Any help would be appricated.

Thank you,
Todd

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1964 Riviera 425 cid

wolfpupsdad
03-20-2015, 09:18 PM
i,m going to try to bring this post back to the top. sence i'm working on a 1956 322 i read some where about using chevy valves in a nailhead. wou;d be alot cheaper then tring to find one type.

Bob
03-20-2015, 10:17 PM
I am away on from home and not able to reference anything, but to my recollection, the problem is not the 11/32 vs 3/8 valve stem diameter that is the problem, but the valve stem length. I would also be very suspicious of your "stock spring pressure", 101@1.16", it is probably wrong.

telriv
03-21-2015, 11:02 AM
Chev. valves are used ALL the time in many apps. DON"T used guide liners. I have made up 11/32nds. cast iron guides for this app. Yours probably need to be replaced in any case. Yes, Chev. valves are longer by about .120" & can be ground down if the tips are hardened for enough cut. On the race motor we have 180pds. on the seat & almost 500lbs. open pressures with NO adverse problems. You will have to buy proper length pushrods if your not using adjustable rockers.
I could go on for days. But, it's not as simple or as cost effective once you've had ALL the nec. machining work done & nec. parts.
If your basically going stock the cost diff. is minimal & increased cost for stock parts is offset by the add. cost of parts & machining.
Just my thoughts.


Tom T.