If you decide to do this. I am in no way,form, size, shape responsible if you mess your head up lol.

Here is my 9 head with all the extra material hanging out into the combustion chambers.



Got it all marked out.




Put my 87mm head gasket on just to see if there was any difference beetween doing it with a block or a head gasket.



Dremmeled them out.

Done head.

No more over hangs.



Here is my friends Kia head that he will be using on his 2.4L build.

 

good job, but its a good idea to use junk valves to protect the seats. nicking seats is no easy fix.

 

Oh ****!!!! I didn't think of it. I did have a few flapped disc contacts with the valve seat. Nothing deep on the 9 head. Nothing deep.
Thanks

 

Nice, so basically your just touching up around the sides?

 

Un-shrouding the valves can be a great performance improvement-- depending on how much material you remove. However, you also lowered your compression. Do you have any idea of the combustion chamber volume before you started? I assumed the 87mm was actually 87cc as the resulting volume measurement?

 

Yup. On the Kia head we just opened it up on the sides. On the 9 head. We did the sides and also the sharp edges around the valves.

 

I will have my machine shop CC the combustion chambers or do it myself as it is supper easy to do just time consuming on my 9 head. I don't really mind if it lovered my CR a bit.

 

if your super **** I would cc each chamber , consistency across all cylinders is more important imo than C/R ( within reason of course). good work , thanks for the choice photos

 

Already talked to my machine shop about getting them CC'd.
No probes. I'm thinking I should start my own build thread lol

 

Big thing you did not do is knock the casting down to the valve seat inserts, that will kill the low lift flow on both the oping and closing of the valve.

About the first .030 lift and the last .030

The fuel mix will be banging into the wall trying to get past the valve.

You may have added 2cc to the combustion chamber by doing the sides.

 

I questioned a good head porter in our area about removing that raised casting right before the valve. he had just ported a friends 4g63 head and I asked him why he didnt blend that into the seat. he was very adamant that that was a big mistake. and this is a guy that has been porting for 20 years. gets flown all around the country and regularly to puerto rico. his heads work fantastic. he did give reasons but my transfer of the knowledge may blurr the original explanation.

 

Ok,

One head I recently ported just cracked 1000 hp, I wonder how much more he could have got if I left the walls there....

 

Is it a good thing to knock it down or no?
Do you have any pictures of how far it should get knocked down?
I can still go back and take more off if needed.
Thanks

 

Can you share those reasons?
Id like to know.
Thanks

 

would be easier if you take some stock valves and have the machine shop make the 45 degree angle razor sharp, basically taking away the margin. This will make it sit flush with the seat so you can get in there and really de-shroud the valves without harming the seat.