Generation IV Internal Engine - Head porting question

just had my heads ported and I am happy with overall service. I see some machining marks around the seat of the valves has anyone else experienced the same? Any reason for concern?

http://s954.photobucket.com/albums/ae21/pkownu/?action=view&current=DSCN0986.jpg

http://i954.photobucket.com/albums/ae21/pkownu/DSCN1001.jpg

http://i954.photobucket.com/albums/ae21/pkownu/DSCN0985.jpg

http://i954.photobucket.com/albums/ae21/pkownu/DSCN0984.jpg

Its weird how in some areas the machining is smooth and around the valves and spark plug hole its more rough. Could it be the cnc program requires more passes in those areas to remove material in steps instead of one deep pass:confused: Or maybe the drill bit was dull and requires replacing?

if it really bothers you , you can use a little sand paper to clean it up. but honestly it looks fine to me.

looks like tool chatter to me.don't know if it will hurt airflow or not.
show the pics to your vendor and tell them what your concerned about.

if it really bothers you , you can use a little sand paper to clean it up. but honestly it looks fine to me.

With all the porting that I have seen I always see smooth surfaces so that the air has laminar flow. I would think it would be especially important around the valves where you need the air to enter and exit the valves as efficiently as possible.

And if you look everywhere else it is smooth. Also do you think with carbon build up in the future these "pits" provide a better anchor to bite into?

Its weird how in some areas the machining is smooth and around the valves and spark plug hole its more rough. Could it be the cnc program requires more passes in those areas to remove material in steps instead of one deep pass:confused: Or maybe the drill bit was dull and requires replacing?

I am no machining expert but I was thinking the same because it did a fine job everywhere else. In the area behind the valve stem (haven't posted pictures) it's beautiful. I can't see this being programmed to have this desired effect.:confused:

Looks like they want to make money and have the cutting depth turned to max income!!! :)

I think they look good. The minor visual blemishes are probably only a couple thousandths difference in material height... will never effect anything. To make it cosmetically perfect would take more time, and probably cost you more...but do nothing performance wise. Its the combustion chamber, no one will ever see it. :)

I'd be worried about that, specifically around the valve. Other than just completely looking like shit, it looks like it may have mangled the top cut on the exhaust seats. I would have the valves lapped for concentricity at the very least, and maybe have the top cut blended in...by hand!

I hate toolpaths across the valve area, I don't know why people do that. You already have the valve center it can follow. It looks like shit, and could loose benifet the 35-37 top cut has.

That sucks. Smooth it out and get rid of the sharp edges at the spark plug area.

It may not look preety, but I doubt it will hurt anything. It seems most of the gains with ported heads are in the runner and valve seat, not the chamber. Were you provided a flow sheet and what did the heads flow?

looks like the bit was just traveling in a opposite direction than all the other cuts, and also looks like around the valve a smaller bit was used.. maybe to get in there better and more accurate.

looks like 90% of the machining on the comb. chamber is horizontal, and the parts that look like "shit" are dont in different directions.. look closely, rub your finger over it... does it feel as "jagged" as it looks, youd be surprised how vision can play tricks on you

For the money that should be blended

WTF did those ?

looks like the bit was just traveling in a opposite direction than all the other cuts, and also looks like around the valve a smaller bit was used.. maybe to get in there better and more accurate.

looks like 90% of the machining on the comb. chamber is horizontal, and the parts that look like "shit" are dont in different directions.. look closely, rub your finger over it... does it feel as "jagged" as it looks, youd be surprised how vision can play tricks on you

It doesn't feel as rough as it looks. I spoke to the porter the bit marks near the seats are because in those spots you are working with bit nose which will not give you the smooth finish. While not pleasant looking I am good with the explanation. I am not going to bother touching them up I will bolt them on and see what the results are. From what I have read I agree with "Star" i think the negative effects will be minimal. Like i said earlier although I never posted pictures of the porting in the runners and the porting in there is pronominal. So in the "porter" I trust thanks for you replies:cheers: