adam1803

iTrader: (65)

I bought a set of LS2 valves for my new heads, the intake valve sits in the seat fine but the exhaust valve doesn't seat like I think it should. Does this look normal or no?

joker machine

I don't think that is normal.

outkast6991

iTrader: (34)

are they stock size. i would expect it to sit flush but i'm no pro

1CAMWNDR

iTrader: (21)

Looks bent to me.

Greg Fell

iTrader: (9)

looks bent to me too. take it out and roll it on a flat surface.

also looks like it has some speckles on it, a sign of detonation. i could be wrong however.

adam1803

iTrader: (65)

The valves and heads are both brand new. Every exhaust valve sits the same way in the seat. The speckles in the picture is actually white paint marks.

outkast6991

iTrader: (34)

are there any nicks in the seat from the cnc hitting it? my heads are getting a valve job because the one that came on them is suspect at best. if you get it figured out let us know

adam1803

iTrader: (65)

Nope, the seats all look fine. I test fitted a couple different valves in every seat in the head and they're all the same.

2xLS1

iTrader: (25)

You don't give any details of the seat sizes in the new heads vs the valve sizes. Was any kind of valve job done on the seats? You need to paint the seats and the valve faces with machinists dye and lap them in with some compound to see where the contact pattern is.

adam1803

iTrader: (65)

The seats are supposed to be stock ls6 sized and fit stock valves, this is from Jason at Katech.

adam1803

iTrader: (65)

Ok, well i took a look at everything real well in some good light and I think thats how its supposed to sit. The angle on the intake valve comes right to the edge of the valve and thats why it sits flush. The angle on the exhaust valve is the same, but doesn't go to the edge of the valve, so it looks like its sticking out more. I can visually see that the angle on the valve mates perfectly with the angle in the seat.

SilverSS

iTrader: (30)

Mine do that. I think the exhaust valve is just thicker.

Hi-Po

iTrader: (4)

But you wouldnt want to paint BOTH surfaces... right? You want to see where blue paint is NOT touching. If you paint both seems to me you will not be able to tell that.

Beaflag VonRathburg

iTrader: (176)

Were the heads pressure tested? I'm guessing a high quality company like Katech would do something so simple.

They typically are and that is my though also.

red fury

iTrader: (1)

Looks normal to me. I just replaced the valves in my PP LS6 heads. The exhaust valves stand out of the head a little more. That is why more clearence is needed on the exhaust side compared to the intake side (PTV).

Beaflag VonRathburg

iTrader: (176)

.800 versus .100 . Exhaust valves are typically thicker. I have quite a few sets laying around and in every single set the exhaust valves are thicker. They are suspect to much higher material stresses due to the added heat of the exhaust gasses. They need the extra material to have comparable structural integrity to the larger, but thinner intake valves that experience less thermal stress.

adam1803

iTrader: (65)

They were bought as bare heads.

vettenuts

iTrader: (4)

My AFR's were similar as well.

Use some fine lapping compound and lap them. That will help with the seal and tell you if the contact surface is incorrect. I just finished doing this on my Dart heads and they colored perfect.