[PTSUPERD]

Can anyone verify that they are better (materialwise to prevent cracking from high heat) than 6.0/6.4 stuff?

From what I gather, they improved on the headbolts versus prior. Just wondering about the heads themselves.

 

[big_stroker]

Aren't they Aluminum heads?

 

[theSLEEPER]

I think so... I remember reading CGI block, aluminum heads, but that was early on during much speculation.

 

[SoGrand]

Yes the 6.7L's have aluminum heads. I have a new 6.7L and they are forsure aluminum.

 

[InnovativeDiesel]

New aluminum cylinder heads replace cast iron to save weight. They feature dual water jackets for cooling and a six-bolt attachment pattern for extra strength. Note the asymmetrical sizes and layouts of the intake (larger) and exhaust (smaller) ports.

Why? The arrangement dramatically shortens the distance between the exhaust and turbo, improving turbo response while protecting nearby powertrain components, like the fuel pump and alternator, from excessive heat. Higher turbo outlet temps also provide extra heat to downstream emissions devices to improve pollution-scrubbing performance sooner while emission catalysts (used to break down harmful pollutants) are warming up.

“Total exhaust volume and surface area of this configuration is about half that of the previous engine,” Gryglak said. “At the same time, we’ve been able to significantly improve the throttle feel of the truck.”

 

[Dzchey21]

I would imagine since they are aluminum heads, the valve seats are probably better than the 6.0/6.4

 

[kyle43335]

i definetly see these heads melting in the future.

 

[tons0torque]

Adequate and even cooling of the valve seats greatly contributes to minimizing any change in the valve lash. There is a large space between the valve seats that uses the cooling ability of aluminum to reduce the heat deformation. An aluminum cylinder head has higher heat conductivity, so it has a lower temperature on the surface of the combustion chamber when compared to a cast-iron design. With a cast-iron test cylinder head, the exhaust valve seat temperature was 608-662 degrees Fahrenheit. With the aluminum cylinder head, which also benefited from a larger space between the valves, the temperature was maintained at 428 degrees or less. The lower temperature enhances durability of the valve seats and increases reliability of the engine as a whole.

This was from an article I read about the Duramax heads. Although it's a Duramax, same principles would still apply to the valve seats. The Chevy guys haven't had any problems with melting heads, so I don't know why the 6.7 would have those issues.

 

[Rob02F350]

guy i work with was reading some materiel from his buddy at the local ford dealer...

tsb's on cracking crankshafts and rods on there test vehicles... i told him i wanted proof.. but if ford was having problems with the test vehicles... they'd fix em right?

 

[Dzchey21]

they wouldnt have released them if they were cracking cranks...

 

[Dzchey21]

i definetly see these heads melting in the future.

duramax's have aluminum heads, they work fine.

 

[bcangelo]

didn't the first couple of years on the d-max have issues with warping the heads. I had a chevy guy at the pump telling me not to buy the first couple year models for that reason, he said that he had one but traded it for an 06 with no problems. I am not a chevy guy anymore so i don't know.

 

[Dzchey21]

I heard rumors, but i never heard of someone actually having issues.

 

[Dirk]

I've seen 1 duramax with a warped heads... and the owner\efi live was the cause.

 

[bigrpowr]

but duramax's sure do break cranks..or at least the lb7/lly did.

 

[sonic blue l]

the 6.7 has a much better coolant flow through the heads then a 6.0l/6.4. The heads are specific to each bank, thus no draw backs of having one head to fit both sides.

 

[CLIFORD3]

but duramax's sure do break cranks..or at least the lb7/lly did.

Got one now with one!

 

[M4K3H808]

with all this testing ford has done they have no room for error with this new motor it should be better!! hopefully! Knock on wood.

 

[RockinJW]

It's not very often that you hear of a Duramax with cracked heads. So the aluminum head should have some advantages, especially with them going back to the 18-bolt pattern.

However, the aluminum head does bring up an issue of gasket sealing. As fire rings are no longer possible (steel ring in an aluminum head cause wear problems). The Duramax guys just started installing a retardly strong stud and hoping it sealed without distorting the block.

 

[Jeff @ Spartan]

i definetly see these heads melting in the future.

Possible, yes. BUT doubtful