How to destroy a 440

[Meep-Meep]

You may want to add a few of those tell tale overheating buttons the rebuilders use. If you use the Edelbrock heads, the RPM heads have better seats and valves than the E Street.

Thanks for that info on Eddy heads. I didn't know. RPM or iron and it may depend on her budget. After paying big bucks for the car fixing this engine is peanuts.

 

[Meep-Meep]

Those don’t look anything like 440 Source heads. These are my new Stealth heads going on my 440 build.

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They have that logo on the runner and the chambers look the same.

 

[ChargerChad]

They have that logo on the runner and the chambers look the same.

I stand corrected. I thought they looked like open chamber heads but when I zoomed in I see you’re right.

 

[dvw]

My bet is the punched thru rocker had zero to do with the failure. You are taking a old stamped rocker, adding spring pressure, adding addition travel in the wear area. Seen them pop a hole thru many times from this scenario. Most times througha rocker back on and it's back in business. Did this a lot when I was young, poor, and lacked knowledge. Knocking the head off the intake could've been a tight guide, nicked stem, who knows. My bet is the cylinder wall crack may have started the whole mess.
Doug

 

[Meep-Meep]

My bet is the punched thru rocker had zero to do with the failure. You are taking a old stamped rocker, adding spring pressure, adding addition travel in the wear area. Seen them pop a hole thru many times from this scenario. Most times througha rocker back on and it's back in business. Did this a lot when I was young, poor, and lacked knowledge. Knocking the head off the intake could've been a tight guide, nicked stem, who knows. My bet is the cylinder wal crack may have started the whole mess.
Doug

The punched rocker wasn't the failed valve. My thought was seeing evidence of the rocker hitting the edge of the retainer (multiple places) and that is what started the chain reaction. Owner admitted she took it to 6000 RPM a couple of times, and with that stock valve train subjected to dual springs and hitting the retainer, it could have resonated badly and came apart. The 5/16 push rods can act like a secondary spring and who knows about those rockers. Well.......a spintron would know. Another guy suggested a seat falling out may have been the cause. I'm not saying no to any of it but hope this is the last of the problems.

 

[RemCharger]

My cousin had a 451 with stealths come apart like this. We had assumed the valve head broke off, but maybe it was started at the seat.. this was a bracket car. More rpm

 

[dvw]

The punched rocker wasn't the failed valve. My thought was seeing evidence of the rocker hitting the edge of the retainer (multiple places) and that is what started the chain reaction. Owner admitted she took it to 6000 RPM a couple of times, and with that stock valve train subjected to dual springs and hitting the retainer, it could have resonated badly and came apart. The 5/16 push rods can act like a secondary spring and who knows about those rockers. Well.......a spintron would know. Another guy suggested a seat falling out may have been the cause. I'm not saying no to any of it but hope this is the last of the problems.

I had noticed that. Just don't think the stamped rockers or small pushrods are the culprit. The seat falling out would definately do it. Not the first wall I've seen cracked like that. If it cracked and overheated without enought press for the seat? Maybe. Incorrectly shimmed rocker hitting the retainer knocking the keepers loose? good possibilty as well.
Doug

 

[Meep-Meep]

My cousin had a 451 with stealths come apart like this. We had assumed the valve head broke off, but maybe it was started at the seat.. this was a bracket car. More rpm

Well that's not comforting. Wonder if there is an issue with Stealth heads and the intake seat press fit? They use A356, which is the preferred material.

 

[RemCharger]

Well that's not comforting. Wonder if there is an issue with Stealth heads and the intake seat press fit? They use A356, which is the preferred material.

Wouldn't be surprised. Who knows who put the seat in with who's equipment? Ever heard of the chrysler 3.6? The old focus split port motors? 5.7Hemis? I was scared putting seats in old cast iron heads.

 

[qkcuda]

One possible chain of events, over revved, valve struck a piston, valve head broke off, piston jammed against valve head and cracked the cylinder, hydrauliced the cylinder, valve head hammering the seat may have caused it to dislodge. Been there, done that, except for the valve seat part, mine had iron heads. Is the rod badly bent? Mine looked like an S.