difference between exhaust and intake valves?
#1
difference between exhaust and intake valves?
hi, I am rebuilding a 52 flathead V8 and looking to but some valves for it, It seems like they all sell exhaust valves, not intake valves. i know there used to be a difference , exhaust were harden steel , but now aren't all new valves the same harden steel ? I did buy 8 valves on ebay, but the heads are about 1/4 inch wider then the ones I took off the engine, they look like they will seat ok tho. any ideas? tony
Last edited by tony1947; 08-14-2021 at 01:16 PM. Reason: pictures
#2
The original OEM intake and exhaust valves were the same size and materials, but the intakes had a depression in the middle with the Ford logo. You can use an exhaust valve for an intake, but not vice versa. It was the valve seats that were hardened inserts but on a '52 you may not have the inserts. Can you post a picture of your valve spring assemblies and the valve seats?
They do sell valves that are oversize, but they require bigger seat inserts. No advantage for the street and a lot of cost. Can you post a picture of the new valves next to an old valve?
They do sell valves that are oversize, but they require bigger seat inserts. No advantage for the street and a lot of cost. Can you post a picture of the new valves next to an old valve?
#4
I don't think your engine has hardened seats on either intake or exhaust. I sure don't see any signs of it. You may want to consider having them added, it is a good idea with gasohol and unleaded gas. You have the "Rotamatic" type valves used from '51-on, which use different valves, springs, and keepers than the earlier engines. Picture of the two types below. You need to be sure any parts you buy are the correct type.
Where did you get those new exhaust valves? I don't see how those will work without major work, maybe not even then. There are Chevy valves sold that are larger than stock but yours look to be even larger than those. Using the Chevy valves requires some special parts steps that are just not worth it in my opinion, for trucks especially.
Where did you get those new exhaust valves? I don't see how those will work without major work, maybe not even then. There are Chevy valves sold that are larger than stock but yours look to be even larger than those. Using the Chevy valves requires some special parts steps that are just not worth it in my opinion, for trucks especially.
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