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351C Hardened Seats Needed???

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Sending my heads to the machine shop in the next week or so. What is everyones opinion on putting hardened seats in? Are the really needed? Do you do both or just exhaust? The engine will have SS valves, 4v quenched heads and be a weekend driver during the summer. Comp is 11.0 :1. The valve seats are in great shape (not recessed, first valve job)

Mark Memmer
70 Calypso Coral Mach 1 351C 4V Completed by 8/01
98 Cobra Convertible
93 5.0 Mustang LX (Winter Ride)
00 Volvo S80 (Wifes Ride)
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I'll throw in my $.02 for what it's worth. I'm not going to fool you ( good thing it's not yesterday ) and tell you I'm an expert on the subject or an engine builder, I'm not. Back in the mid eighties I did a lot of reading on the subject, mostly out of curiousity. What seemed to surface was that, unless the engine was running under heavy loads all the time, such as a truck, it's not too much of an issue. Infact the lack of lead will actually prolong engine life with reduced wear. A while back, while thumbing threw a magazine on the news stand, there was an article on building up an early Chrysler Hemi, the builder said the heads were hard enough and didn't need hardened seats and never saw any problems in past engines he built ( Hemi's ) with unleaded gas. He did use s.s. valves.

Now in saying that, If it were me, I'd ask the builder anyway and if it's not too expensive to do, why not. Since you're running a high compression, I take it, that your engine is going to be on the radical side. Think about it, you'll probably have the engine apart to freshen it up way before wear from the unleaded gas show up and have the seats tuned up while the engine is apart. You wouldn't do a ring, bearing and valve springs with out touching the seats, would you?

You can do anything you want to......ONCE!
aka "my 66 coupe"

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