Mr. RustyRatRod and the 516 head.

[moparmarks]

I just picked these up in Vegas. Would like to use them on a 440 with a .540-.580 roller cam. I'm a little concerned about the valve stem boss. Is a little rough.
Thanks:tongue7:

 

[RustyRatRod]

You mean the valve guide where it protrudes into the port? I've seen a lot worse. They look to have been ported and the larger 1.74 exhaust valves installed. I'd run the hell outta them.

 

[moparmarks]

Ya they have the 1.74 E-valves. Does it look like they have hardened seats installed?

 

[RustyRatRod]

Caint tell with the valves in. But honestly Mark, it's not that huge of a deal. Opinions vary, but that's mine. I'm not having hardened seat installed in the ones I have.

 

[moparmarks]

Thanks Rusty. I do plan on running the hell out of them. Going in my 440 Dart.

 

[GTX MATT]

Caint tell with the valves in. But honestly Mark, it's not that huge of a deal. Opinions vary, but that's mine. I'm not having hardened seat installed in the ones I have.

I'd agree with Rusty here, I don't think that the hardened seats are all they are cracked up to be. Are they a bad thing? No, absolutely not. That being said I've not seen many cases of valve recession on older Mopar iron heads. While I'm not the most experienced wrench due to my age, I've personally had a few engines apart that had some serious miles and abuse on them. One had .028 bore taper (yes, .028, it had almost bored itself .030 over) and must have had 350+ miles on it. It had two burnt valves, but no sunken valves. These were 516s off of a '66 440. Apparently it ran, although I could only imagine how bad. It would have made Old Christine sound like brand new.

I've had another off of a 260K + 383 that had had been thoroughly beaten for the second 160k on unleaded gas. It had one burnt valve, and that valve showed slight recession, although not very severe. A valve job probably would have sufficed, and if going to 1.81s it would have been fine.

Moral of the story? Will they sink? Sure, but you're going to have to abuse it for a while. Most of these engines will probably never see 50k miles again, and almost certainly not before someone pulls the heads off for freshening or hot rodding. Also remember that not every machine shop is competent enough to install them, so you run the risk of a failure related to them.

 

[Garys1969RR]

Those heads will prob work great! Looks as if the area just under the valve seat is still the stock size. This is prob the biggest restriction to ex flow. If you can, have a head shop open up that area. It will greatly improve air flow. I installed 1.81 ex valves in my 915 heads, and opened up that area. Big improvement.

 

[747mopar]

I have to buddies that run 906's without hardened seats without any trouble plus I've seen port jobs where that area your talking about was almost completely removed. Run em

 

[RustyRatRod]

I agree with Gary 100%. It's worth lettin your machine shop have a look. The bowl area is where probably 80% of the flow of porting is to be had. It's that important. ...and for the 516 haters, remember this. Though the 516 castings may have slightly inferior ports compared to the 906 and other open chamber heads, the 516s have quench and if properly taken advantage of, I think that levels the playing field a good bit.

 

[Meep-Meep]

I'm not worried about that little bit of guide boss in the exhaust port. I pretty much removed it on my 915's. Those valves look like 2.08 / 1.74 to me.

 

[bm02tj]

If this was a motor that was going to see heavy use like towing or heavy truck
yes to hard seats
no unless you are going to run propane