Indy LAX heads

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The valves will just keep sinking........

A couple years ago I had a set of SBF 289 heads that had some the exhaust seats recessed about .250”
I’d never seen any that bad.

Then a couple months later I had a set of 1967 Pontiac heads come in that were just as bad.

Here’s one from a J head that was on that path....

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Ok I talked to the customer and he understands. A few updates on them. He bought them from Indy with a few upgrades (2.02 valves, double springs, ect). He ran them a few years and during that time broke two springs running an .528 cam and said the car never preformed like he expected. I recommended finding someone local in his Ohio area that he could work with. He’s in the market for TrickFlow heads so at that point he would probably be better off selling them.
 
This is the first time I have seen an L/AX or M/AX head with miles on them. Surprised by that much recession in the seats.

There are no seat inserts there, right? I don’t see any obvious lines from them so I assume no inserts.
 
PRH said:
That’s just typical valve seat recession........

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Hmm.. It's a lame debate ..but ok..so without having the heads physically in front of me to see.. but let's think about this for a second ..this is an aftermarket head ind hard seat with hot rod mileage ..'low'... sinking that much? Not typical.
The j head is definitely sunk, has the classic double ledge where the valve od diameter starts wearing into the top cut leaving half of it behind. The old thing to do was to drop a 90 to put a cup around the exhaust so nothing came back in ...and that's what is there...indy cyl has been around for what 50 yrs or more. That's my opinion.
 
Bobzilla said:
This is the first time I have seen an L/AX or M/AX head with miles on them. Surprised by that much recession in the seats.

There are no seat inserts there, right? I don’t see any obvious lines from them so I assume no inserts.
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They are an induction type hardened seat.
Read my post before this one and it might shed light.
 
mgoblue9798 said:
Would a 15 deg cut get rid of most of the lip?
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If you use a set 3-4 angle seat cutter the 15 degree isn’t usually on them. I don’t think any of mine do. My best cutter is technically a racing cutter with a 70-60-45-30 and on Edelbrock heads I’ll hand cut a 15 with my Neway cutters. Many are only 60-45-30.
 
pittsburghracer said:
If you use a set 3-4 angle seat cutter the 15 degree isn’t usually on them. I don’t think any of mine do. My best cutter is technically a racing cutter with a 70-60-45-30 and on Edelbrock heads I’ll hand cut a 15 with my Neway cutters. Many are only 60-45-30.
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I understand. I wasn't trying to give advice, I wanted to learn if it could be fixed either by stone or cutter with 15 degree angle or if the seats are too far sunk to do anything with other than put new seats.
 
mgoblue9798 said:
I understand. I wasn't trying to give advice, I wanted to learn if it could be fixed either by stone or cutter with 15 degree angle or if the seats are too far sunk to do anything with other than put new seats.
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They can be. He doesnt have time for it and I understand completely, even sympathize. It's just not something people always wanna deal with, both partie$. It can turn into more than just stone drops, you can find yourself back holding the die grinder and even milling to get back where you were chamber cc.
 
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