Aftermarket valves?..

[Jmmahon]

Ok I took apart a head that I bought for a build I'm doing and when I pulled the valves the seats looked great so I cleaned the valves up and as I was I noticed some markings on the end of the valve stem's.. It was in the exhaust side at the end. As you can see there is four valves that are different looking on the exhaust side, it is those ones that have the markings

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. I couldn't get a picture because my camera can't focus on something that small. But it looks like it's the sealed power logo? And stamped beside the logo it says "v 2653 HHP" anyone know anything?

I also noticed the intake side had the same logo and similar markings!

 

[Colt4G63 also]

Seems lame that they don't match. What does that do for combustion chamber size?

 

[Jmmahon]

The valves are identical on the bottom, seats and all..

 

[Colt4G63 also]

By bottom, do you mean the side that faces toward the sky when mounted in the engine? Because the bottoms of the valves that I see in that picture are clearly different.

Half of them have a large indent, and the other half have a small indent. Maybe it doesn't make that much of a difference; I don't really know.

 

[Jmmahon]

Sorry to confuse you, I meant the top of the valve where it seats. But yes the bottoms are different, not sure why... I would really like to know if these are aftermarket valves or not?..

 

[TurboDSM90]

The valves with "6T" are OEM valves. The others are some sort of aftermarket replacements which will have an effect on cylinder to cylinder compression.

 

[BogusSVO]

With the different mix of valves, the head has been rebuilt before. good chance it jumped time and bent the factory installed 6t valves.

Check the guides for cracks.

 

[Ghost_92TSi]

It could possibly have the same compression as the stock ones. A 2 ft deep x 2ft wide hole has the same space as a 1ft deep x 4ft wide hole. The deeper one doesn't go all the way to the lip, Has the appearance of being deeper with a sharper indent.

 

[BogusSVO]

The dish in the valve head will alter the CC to a minor point. Once the head is assembled the combustion chambers can be CC'ed to figure compression ratio

I would be more concerned with the construction of the valves, if they are 2 piece design or not

I personally will not trust most aftermarket parts stores replacement valves in a turbo build.

 

[Miasma]

Just by looking at your head deck surface, and looking at the main oil port it looks as if it has been resurfaced before. Do you know if it has been or not?

The main oil port (tear drop shapped port, top lest corner) in your first picture looks very shallow from the surface of the deck. You might want to look up how to port this a little more, to make sure you have good oil flow going into your head, so your valve train doesn't suffer.

 

[Jmmahon]

I don't believe it has been messed with, I cleaned it a lot..

 

[BogusSVO]

I bet it has been surfaced, just from the glare on the surface of the last pic. It looks like it was milled on a wet segment stone surfacer.

Best way to tell if it has been milled and how much is to measure the head thickness,

http://www.dsmtuners.com/forums/cyl...how-measure-4g63-cylinder-head-thickness.html

The oil port mod is found here

http://www.dsmtuners.com/forums/newbie-forum/341028-4g63t-head-oil-port-mod.html

 

[BogusSVO]

I bet it has been surfaced, just from the glare on the surface of the last pic. It looks like it was milled on a wet segment stone surfacer.

Best way to tell if it has been milled and how much is to measure the head thickness,

http://www.dsmtuners.com/forums/cyl...how-measure-4g63-cylinder-head-thickness.html

The oil port mod is found here

http://www.dsmtuners.com/forums/newbie-forum/341028-4g63t-head-oil-port-mod.html

 

[BogusSVO]

Did you get a set of stainless steel valve or hunt up some more 6t valves to replace those parts store valves?