273 Buildups - Status Checkin

toolmanmike said

Good point. The machine shop should catch all of that. What do you think is better, hardened seats or stainless valves. The guys at the machine shop that
will do my heads recommended just stainless valves. I only drive a few thousand miles a year and the stainless valves flow better and will last a long time. I've heard some horror stories about replacement seats falling out. What's your opinion? MIke

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I wouldn't worry about adding seats. If the heads are nice a good valve job will be all you need. My old boss has been building engines for 20 years and never uses hardened seats unless the seat is damaged. He builds mainly performance stuff too.
As stated my 273 had new seats installed before a got it, it was a mess, some were too low and one was cut to the water jacket. I pulled them all out and replaced them, adding some bearing/sleeve sealer to the bad one and have not had any coolant problems.
With the amount of driving we do with these cars you will not see them eroded. Also the use of performance cams (more duration) the seats do not get as hot as say if it was truck that you used for towing.
Are you doing any port work? I cut my seats on a Serdi with the deep bowl cutter, also went in and cleaned up the bowls and ports some with a carbide and some sanding rolls.