welding heads / seats falling out / heat treating heads?
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Re: welding heads / seats falling out / heat treating heads?
Tim, my journeyman welder (NASA, etc) uses MIG for aluminum head seat repair. Cleanup is a mess but the heads don't seem heat affected. Just a thought.
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rebelrouser
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Re: welding heads / seats falling out / heat treating heads?
As mentioned, you are just going to have to trust the shop doing the work. stress imparted during the welding will relieve itself as the heads go through heat cycles, which may cause a seat to fail, or also as mentioned move and lose seal. My next concern is how thin will the heads be when final porting is done? I have seen aluminum heads parted so thin the seats would move when you torqued them down. Also, not what you want to have happen after spending good money for the welding and machine work.
Maybe it is really time to think about a nice brand new set of heads.
I actually just went through this scenario on an engine building for myself. A 440 mopar with a cross ram for nostalgia racing. Had an old set of 516 closed chamber heads on the shelf for years, put some bigger valves in them, ported them, flowed real good on the bench, fired it up on the dyno ran it several times adjusting carbs, etc. First hard pull at 4,000 rpm made almost 500 ft. lbs. torque then a cylinder got cold, pulled out the plug and water ran out, head had cracked under a hardened exhaust seat. All I really lost was a lot of my time for me. Guess what, there is a shiny new set of trick flow 270 heads on my work bench. What the hell, I deserve it right?
Maybe it is really time to think about a nice brand new set of heads.
I actually just went through this scenario on an engine building for myself. A 440 mopar with a cross ram for nostalgia racing. Had an old set of 516 closed chamber heads on the shelf for years, put some bigger valves in them, ported them, flowed real good on the bench, fired it up on the dyno ran it several times adjusting carbs, etc. First hard pull at 4,000 rpm made almost 500 ft. lbs. torque then a cylinder got cold, pulled out the plug and water ran out, head had cracked under a hardened exhaust seat. All I really lost was a lot of my time for me. Guess what, there is a shiny new set of trick flow 270 heads on my work bench. What the hell, I deserve it right?