Anyone have pics of sunken valve seats???

[Blakcharger440]

I have always heard about bigblock 906 and 915 heads not having hardened valve seats and that with todays gas the valves will sink.
Does anyone have a pic or two of some heads in which the valves are sunk? What does this actually look like and to what degree as I dont think I have seen a set that have sunk.
Please someone post a pic...I know its pretty morbid but I wanna see!!!

[Chryco Psycho]

I don`t have a pic handy but i have seen some seats sink 1/4 in bad cases & split the valve head

[TylerCharger69]

I saw a ford head that the valve was actually sunk in over an inch!!!    I'm surprised the car was driven to that extreme.

[deputycrawford]

I used lead additive in my 383 with 906's and the valves sunk so bad I'm surprised it still ran. Pulling the heads and getting the hardened exhaust seats isn't that bad. Nor does it take very long.

[Challenger340]

Remind me in "pm", and I'll take a photo for you.
Also, I'll show you how to measure to see the "degree" of sunkeness, or, how to tell if you need new seats.
Bob out.

[AKcharger]

[Nacho-RT74]

thank GOD I have 452s heads.

[Blakcharger440]

Hey AKcharger could you make that pic larger??? 

[is_it_EVER_done?]

Here is one I saved from someones post a couple months ago. I saved it because it's a good example of how much a valve can recede, yet still have the engine run ok except for a substantial reduction in power.

[tan top]

Here is one I save from someones post a couple months ago. I saved it because it's a good example of how much a valve can recede, yet still have the engine run ok except for a substantial reduction in power.

                    never seen one pounded that far in before 

[Mefirst]

-Damn!!!

[TylerCharger69]

When I worked in a machine shop in Blythe California...we pulled a head off and found a valve sunk in about an inch!!!   I wish I would've taken a picture of that back then.   The guy apparently didn't care that the car ran funny.......just kept his foot in it I guess.    The motor had a rod thrown through the oil pan (302 Ford)  so the engine was toast, but the seat issue was repaired  and hardened seats replaced the originals so he had a set of heads to put on the for sale shelf anyway.

[AKcharger]

thank GOD I have 452s heads.

Now there's a question...I was told by the proverbial "someone" that the 452's were treated with an electric/heat type hardening and if you cut the valve seats during the valve job you'd "cut away" the hardening, any truth to that?

I picked up a set of 452's so I wouldn't have to install $400 worth of valve seat like in my 915's on my 383 now

[is_it_EVER_done?]

Now there's a question...I was told by the proverbial "someone" that the 452's were treated with an electric/heat type hardening and if you cut the valve seats during the valve job you'd "cut away" the hardening, any truth to that?


Though I can't say if my informations is accurate or not, I did research this about 25 years ago. From what I was told by a couple of high end head shops (also Dick Landy himself), as well as Chrysler's tech line, the 452's have Stellite (Sp?) seats, whereas the earlier hardend (post 906, but pre 452) heads had flame, or inductioned hardend seats.

Supposedly the 452's by virtue of there Stellite seats, can be ground without problem, but the earlier "surface hardend" seat heads loose theire hardness with anything more than a touch up.

Like I said, I don't know if it's accurate, but I have never had a problem with 452's.

[Nacho-RT74]

I have just in case two 452 heads sets more and a pair more NOS available ( 6 in total )That I know nobody will buy because nobody more knows they exist at dealer storage .

Milling down with the special grease to get valves seated ( sorry, dunno the exactly english words to describe that job ) is almost unnapreciable. The hardened job is a little bit more than just the surface as my knowledgement

[TylerCharger69]

Nacho....that would be "lapping"  if your speaking of seating the valves.  The tool looks like a small suction cup with a handle   and the lapping compound is used in a vigorous twisting motion.  When I had my heads redone.....the seats that were put in were like 3/4 of an inch in thickness and were machined to fit into the heads.  So.....when you speak of doing that  it would be known as "lapping in the valves". 

[Nacho-RT74]

thanks new vocabulary learnt...

[Bandit72]

Here is one I save from someones post a couple months ago. I saved it because it's a good example of how much a valve can recede, yet still have the engine run ok except for a substantial reduction in power.

                    never seen one pounded that far in before 

i'll ask my buddy if he still has the heads off of his windsor in his bronco...they are pounded farther in than those 

[Blakcharger440]

Here is one I save from someones post a couple months ago. I saved it because it's a good example of how much a valve can recede, yet still have the engine run ok except for a substantial reduction in power.

                    never seen one pounded that far in before 

Now that is what I wanted to see!  No doubt about it those heads took a beating! 
Thanks for posting the pics!