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Re: Undercover cnc porting?

Posted: Sun Dec 09, 2018 5:34 pm
by Carnut1
Resized_20181209_151600_5416.jpeg
pcnsd wrote: Sun Dec 09, 2018 5:14 pm Charlie,
The problem I see is that it does not have the defined tool path direction changes of a machine cut. Machine port work stands out to anyone that has seen it before.

CNC_Cylinder_Heads.jpg
I thought I did pretty well following the contours.

Re: Undercover cnc porting?

Posted: Sun Dec 09, 2018 7:04 pm
by cv67
shoedoos wrote: Sun Dec 09, 2018 4:11 pm If I were the inspector, first thing I would think is "he's run a sand roll over the cnc work.....why would he do that? There must be more to this......"

You wouldn't get a pass from me without some serious explaining....
This

Re: Undercover cnc porting?

Posted: Sun Dec 09, 2018 8:55 pm
by swampbuggy
Tell what was interesting about the flowbench results please Charlie, i am interested in knowing, if you do not mind sharing ? Mark H.

Re: Undercover cnc porting?

Posted: Sun Dec 09, 2018 9:06 pm
by 1972ho
Wow cnc port cheaters,Unbelievable here they let you have a ported head and still that’s not enough,let’s just cheat it and see how much we can get away with.

Re: Undercover cnc porting?

Posted: Sun Dec 09, 2018 9:47 pm
by Carnut1
1972ho wrote: Sun Dec 09, 2018 9:06 pm Wow cnc port cheaters,Unbelievable here they let you have a ported head and still that’s not enough,let’s just cheat it and see how much we can get away with.
I am not a fan of cheaters. I would rather win through hard work and research. It was an interesting conversation between the racer and the cnc guy. The cnc guy didn't like calling it cheating he called it," Seeking a horsepower advantage!"

Re: Undercover cnc porting?

Posted: Sun Dec 09, 2018 9:54 pm
by Carnut1
swampbuggy wrote: Sun Dec 09, 2018 8:55 pm Tell what was interesting about the flowbench results please Charlie, i am interested in knowing, if you do not mind sharing ? Mark H.
I did that fake cnc cut on a stock intake and exhaust and with the roughest texture I can imagine flow increased. Yes, the port volume went up and the shape was as similar to stock as I could keep. The increase in flow was not across all lifts. Thanks, Charlie

Re: Undercover cnc porting?

Posted: Mon Dec 10, 2018 9:26 am
by winterhoff
It's easy to do i have done a lot of it . If your wanting to cover up a CNC head or a hand ported you need a pressure pot type blast cabinet and steel shot stone the whole port tape everything with Gorilla tape you don't want to blast like machined surface plug guide bores and put old spark plugs in and play with air pressure in the cabinet
If you want to know more you can call me
Ron's Porting Service
636 447 4042

Re: Undercover cnc porting?

Posted: Mon Dec 10, 2018 9:44 am
by Carnut1
winterhoff wrote: Mon Dec 10, 2018 9:26 am It's easy to do i have done a lot of it . If your wanting to cover up a CNC head or a hand ported you need a pressure pot type blast cabinet and steel shot stone the whole port tape everything with Gorilla tape you don't want to blast like machined surface plug guide bores and put old spark plugs in and play with air pressure in the cabinet
If you want to know more you can call me
Ron's Porting Service
636 447 4042
Your name actually came up in the conversation between cnc guy and racer guy.

Re: Undercover cnc porting?

Posted: Mon Dec 10, 2018 10:43 am
by PRH
I’ve seen a variety of “optimized” heads over the years, done in a variety of different ways, that had varying degrees of the “stock” look.

They’ve never looked truely “stock” to me, but I could see where they’d pass tech....... unless there was an actual stock one sitting on the bench next to it.

Re: Undercover cnc porting?

Posted: Mon Dec 10, 2018 10:48 am
by Rowdy Yates
No go on fooling anyone or cheating as said by Carnut. Dead give away is the cnc grooves. Have Chris Frank cnc ported Ls3 heads and hand ported Ls 7 heads by D. Morgan. Looks as if a builder just went over the cnc program to get the perfect CSA for the intended Rpm. Tweaks...... After the cnc.

Re: Undercover cnc porting?

Posted: Mon Dec 10, 2018 11:26 am
by dfarr67
I was looking for a set of GM Fastburn heads a few years ago and there were some sets that came up that were 'optimized' but didn't pass tech. There was never enough information for me to make a purchase at the time- went AFR instead.