Cylinder head question

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Tadams

Tadams
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In doing a rebuild on my stock 1965 273 commando. Retired so not trying to spend a lot. Pulled the heads and a couple of exhaust valve seats look bad. I haven't taken them to a machine shop yet. From what I've read the exhaust valve seats should be upgraded anyway.
Looking at options. I know a 318 would not be that expensive but would like to keep the 273. Any idea of cost to have hardened seats installed

Message_1563026648610.jpg
 
Looks bad? That head looks like complete garbage. I'd be looking for a newer set of 318 castings with hardened seats to refresh.
 
If it's only TE exhaust side that looks like that I'd buff them off, install had seats and never look back.

I've fixed way worse. For a complete head rebuild with hard seats is $450.00 where I come from.
 
That rough surface in the combustion chamber is going to lead to hot spots and pre-ignition. Replace these heads, they have been stored badly.
 
Damn man! Golf balls are smoother than that. Have you considered a set of EQ heads?
 
Looks for a set of #302 casting heads. Similar combustion chamber, port sizes, update to newer intake bolt size and angle, and hardened seats. (or you can use any 318 head. STAY AWAY FROM 340-360 HEADS! They have too large of chambers and ports to work well on 273's.
 
What year 318 heads. Have to change intake as well?
 
What year 318 heads. Have to change intake as well?
If you want to use your 273 intake you will need 64 or 65 cylinder heads. If you use 66 and newer heads you can use the newer intakes. Best to use ones designed for 273/318. 340/360 intakes will work but there is a port mismatch.
 
When did the 318 begin to use hardened valve seats. I'm going to finish disassemble of the engine before making any decisions. Really would like to keep the engine if possible.
 
If it's only TE exhaust side that looks like that I'd buff them off, install had seats and never look back.

I've fixed way worse. For a complete head rebuild with hard seats is $450.00 where I come from.

The intake seat looks horrible, and I'm not sure exactly how to describe the exhaust.:D
When I first glanced at the picture I thought it was a gopher hole in someone's yard.
 
Pistons and cylinder walls are good. Valves are not bent or broken
 
When did the 318 begin to use hardened valve seats. I'm going to finish disassemble of the engine before making any decisions. Really would like to keep the engine if possible.
Just a guess, in 1985
 
I have a nice set of 64 64 273 heads, complete. Get some stainless exhaust valves and never look back. $100 for the pair. Let me know. You are 4 hours away, maybe meet in the middle.
 
I have a nice set of 64 64 273 heads, complete. Get some stainless exhaust valves and never look back. $100 for the pair. Let me know. You are 4 hours away, maybe meet in the middle.
That would be awesome. I am not able to start a conversation with you if you would like to try me
 
In doing a rebuild on my stock 1965 273 commando. Retired so not trying to spend a lot. Pulled the heads and a couple of exhaust valve seats look bad. I haven't taken them to a machine shop yet. From what I've read the exhaust valve seats should be upgraded anyway.
Looking at options. I know a 318 would not be that expensive but would like to keep the 273. Any idea of cost to have hardened seats installed

View attachment 1715363812

Chances are they're savable.
Blast them 1st to see what's left if its lower than the exh seat all around from rust pits... then get new heads.. as for pinging from it.. nope....Pits dont make that happen... raised or sharp hot spots do.
If not, get the set from 66, good deal.
 
Tadams, What are the casting numbers on your heads? That will enable you to tell the year and whether or not they are closed chamber heads and to get an estimate on the cc's of the combustion chamber.
 
to answer an above question
the 302 (years given above) or EQ heads make the most sense (with late intake)
getting 273 heads ok but late chamber is better and you have to figure guides and seats
I use durabond premium seats- sintered
 
I have picked up the heads from 66fs. He is a great guy, extremely knowledgeable. He met me as he was heading to Colorado.
 
cool keeps it original do your homework and you specify the seats and guides
I like spiral id guides to hold some oil in today's unleaded gas and cut for viton seals
I od hone the valves to check for straight and to provide finish
some cheap valves act like files the grind is done so quickly
 
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