AFR head crack

[TMSJoe]

How old are the heads? Sorry if it was answered before. The crack looks just like a stress crack from age. I see this a lot on SBC and other heads. 2.5 Chry comes to mind. Until it migrates past the gasket I wouldn't worry about it. The picture does look as if there is a line migrating from the ex seat but it could be just a scratch.

[Franco]

Heads have 2 seasons on them and not many runs. Crack runs from bolt holes on both heads outward.

[Franco]

Ok I understand my heads are tired/used up whatever the case may be but I could still use some help. I had a few thou taken off the deck to clean it up and the seats touched up and replaced all the intake valves due to one being "stretched/tuliped" whatever its called. Intake valve lost lash. Checked all springs and pressure tested heads and replaced all 4 intake valves with new AFR argentina valves as its the only shelf valve available.

Went to the track and went back to the old safe tune up it ran reliably on and lost lash on all 4 new intake valves on the third pass. Plugs looked good no signs of detonation crazy heat or lean.

The valves in the other head seem to be fine no change in lash etc. What is causing this issue ?

[rookie]

Ok I understand my heads are tired/used up whatever the case may be but I could still use some help. I had a few thou taken off the deck to clean it up and the seats touched up and replaced all the intake valves due to one being "stretched/tuliped" whatever its called. Intake valve lost lash. Checked all springs and pressure tested heads and replaced all 4 intake valves with new AFR argentina valves as its the only shelf valve available.

Went to the track and went back to the old safe tune up it ran reliably on and lost lash on all 4 new intake valves on the third pass. Plugs looked good no signs of detonation crazy heat or lean.

The valves in the other head seem to be fine no change in lash etc. What is causing this issue ?

Did you reset them to see if they would stabilize?

How much did they lose?

I always check mine several times on a fresh or rebuild the first night out until I know they are stable.

[TMSJoe]

... replaced all the intake valves due to one being "stretched/tuliped" whatever its called.

Went to the track and went back to the old safe tune up it ran reliably on and lost lash on all 4 new intake valves on the third pass. Plugs looked good no signs of detonation crazy heat or lean.

The valves in the other head seem to be fine no change in lash etc. What is causing this issue ?

A tuliped intake valve IS a sign of detonation. I see this on boats all the time.

Are you checking and repairing both heads or just one side? All new intakes...... lost lash in all 4...? So you only have one head off I assume? Are they both the same chamber volume?

[Franco]

Ok I understand my heads are tired/used up whatever the case may be but I could still use some help. I had a few thou taken off the deck to clean it up and the seats touched up and replaced all the intake valves due to one being "stretched/tuliped" whatever its called. Intake valve lost lash. Checked all springs and pressure tested heads and replaced all 4 intake valves with new AFR argentina valves as its the only shelf valve available.

Went to the track and went back to the old safe tune up it ran reliably on and lost lash on all 4 new intake valves on the third pass. Plugs looked good no signs of detonation crazy heat or lean.

The valves in the other head seem to be fine no change in lash etc. What is causing this issue ?

Did you reset them to see if they would stabilize?

How much did they lose?

I always check mine several times on a fresh or rebuild the first night out until I know they are stable.

Valves were lashed at .018 and all 4 lost all lash and were not sealing completely. Had a strange noise (whistle/sucking) after a pass and decided to pull valve cover. Resetlash made a pass and same noise came back loaded car and havent checked lash again but will later.

[Franco]

... replaced all the intake valves due to one being "stretched/tuliped" whatever its called.

Went to the track and went back to the old safe tune up it ran reliably on and lost lash on all 4 new intake valves on the third pass. Plugs looked good no signs of detonation crazy heat or lean.

The valves in the other head seem to be fine no change in lash etc. What is causing this issue ?

A tuliped intake valve IS a sign of detonation. I see this on boats all the time.

Are you checking and repairing both heads or just one side? All new intakes...... lost lash in all 4...? So you only have one head off I assume? Are they both the same chamber volume?

So it can detonate enough to tulip 4 new intake valves but not show any signs of detonation or excessive heat in the plugs? Both heads were off and light surface, only the 4 intakes in one head were replaced as that was the head with 1 prior tuliped valve but it sawed off 3 ground straps so decided to replace those valves other head looked ok.
Lost all lash and some valves were leaking not seating complete.

As far as chamber volume they have been surfaced equally as far as I know.

[Franco]

Put some valves in the other car recently and they also became paper weights in just a few runs. I found some humor in the situation when the new valves showed up with made in argentina crossed out.
Maybe it would be easier to just ship them without the bag instead of having someone cross them out.

[TMSJoe]

As far as chamber volume they have been surfaced equally as far as I know.

I had a pair of heads delivered to me by a customer. I opened the first head and started to do some grinding to smooth out some edges here and there. When I got to the second head it became obvious that this was NOT a pair. The second head was 64cc and the first was 76cc. Summit wanted the pair shipped back but I had done work to them. The customer gave me the wrong head and had me sell him the correct head to match.

Moral of the story... Measure both heads before you assume they are the same. What I am reading is you assume they are the same, not I measured them both and they are the same.

[flyingwedge]

On a lesser note, have you considered a thermal coating for the chambers and exhaust ports ? Sounds like the heads need some help. Good Luck, flyingwedge.

[Engguy]

Put some valves in the other car recently and they also became paper weights in just a few runs. I found some humor in the situation when the new valves showed up with made in argentina crossed out.
Maybe it would be easier to just ship them without the bag instead of having someone cross them out.

This is not good. Another case of trying to save a buck, but costing upwards to many many thousands more. AFR FROM ARGENTINA? If they get valves from there what else comes from there? This changes my positon on AFR. I hope DART doesn't do the same stupid stuff.

AFR if you want to out source to a different country try Germany or Japan.

[Engguy]

Ok I understand my heads are tired/used up whatever the case may be but I could still use some help. I had a few thou taken off the deck to clean it up and the seats touched up and replaced all the intake valves due to one being "stretched/tuliped" whatever its called. Intake valve lost lash. Checked all springs and pressure tested heads and replaced all 4 intake valves with new AFR argentina valves as its the only shelf valve available.

Went to the track and went back to the old safe tune up it ran reliably on and lost lash on all 4 new intake valves on the third pass. Plugs looked good no signs of detonation crazy heat or lean.

The valves in the other head seem to be fine no change in lash etc. What is causing this issue ?

Lost lash, valve is stretching, and or very soft and the face is receeding into the seat. Argentina what do you expect? The foundry likely ran out of what ever they made the first set of to spec valves of, to impress the AFR guys with. So they just fill the order, pocket the cash, and say good luck AFR. And AFR welcome to the money saving deal of outsourcing to other countrys.
So who makes a good head? My list keeps getting shorter.

[dirtracr5]

buy bare heads and put your own parts in. i have never and probably never will buy complete heads.

[Wolfplace]

This is not good. Another case of trying to save a buck, but costing upwards to many many thousands more. AFR FROM ARGENTINA? If they get valves from there what else comes from there? This changes my positon on AFR. I hope DART doesn't do the same stupid stuff.

AFR if you want to out source to a different country try Germany or Japan.

Are you serious?
Where do you think much of Ferrea comes from?
REV?
Most of Manley?
Not to mention many very particular OEM's
Are these all junk too?

Some reading for you
http://www.basso.com.ar/eng/highlights.html

http://forum.lsxtv.com/showthread.php?p=3270

[Franco]

I dont care where they are made if they have some sort of quality. I just think its funny the ones I got a while back said made in argentina, now the most recent ones came with the writing crossed out.

Just to be clear the most recent valves are for a different set of heads on a different engine.