CNC porting head porting or the "old fashioned way"

greeneyegi

Well-Known Member
Joined
Feb 21, 2010
TA Intimidator and Champion intake
Which way should i go?
this is my first set of Aluminum heads. T
I have a feeling the first thing someone is going to ask is how fast or how much?
Well the how much is obviously gone out the window 30k ago.
And the how fast is how "fast as the part will allow me to go?"
The cnc porting is as much as the heads cost.
the old fashioned way probably wouldn't be much different.
I havent seen any side by side flow numbers. Are there any?
Let me know of anybody who can port this setup i have and flow
it for me?
Im in N California.Im running a ported set of stock 8445s now
i want to compare what this setup does.no change to bottom.See what the trap
speed does.
 
TA Intimidator and Champion intake
Which way should i go?
this is my first set of Aluminum heads. T
I have a feeling the first thing someone is going to ask is how fast or how much?
Well the how much is obviously gone out the window 30k ago.
And the how fast is how "fast as the part will allow me to go?"
The cnc porting is as much as the heads cost.
the old fashioned way probably wouldn't be much different.
I havent seen any side by side flow numbers. Are there any?
Let me know of anybody who can port this setup i have and flow
it for me?
Im in N California.Im running a ported set of stock 8445s now
i want to compare what this setup does.no change to bottom.See what the trap
speed does.


This is a really loaded ?

Who's CNC program Vs Who is porting the heads the old fashioned way .. this is what it boils down to...

If your looking to Extract every last bit out of a cylinder head .. OLD FASHIONED WAY if you know a top notch porter ( they are few and far between) ..

OLD fashioned way with a elite porter will usually take a long time to get .. they are backed up at least half year out .
CNC can turn things quickly and use a cookie cutter approach ..

with the CNC they are only as good as the initial porter .. with a CNC program some "trade secrets " can't even be replicated .

Price CNC is more cost effective .. the high end old fashioned porters will easily charge $1500-$2K or more depending on what you are asking for.

I guess what you need to ask yourself is just how hard are you wanting to push the heads because the limitations will fall on other components not on the heads.
 
That shows how much i really know.
But it explains how much ive got to really learn.
thank you that explains it very clearly.
I will just have TA do the CNC for me ;)
 
That shows how much i really know.
But it explains how much ive got to really learn.
thank you that explains it very clearly.
I will just have TA do the CNC for me ;)



Is it a 8 second car .. because out of the box GN'1 run 9's all day
 
I havent dynoed. But I have ran a 128mph with my combo @ 3900#
Looking to go 135-140 easily (without having to tune that out of it)
Should be able to tune some real good low passes out of that trap!
I want to get the most out of the heads.Then the best turbo for these heads
then etc.
 
I've ported more then acouple sets of heads and actually just finished my TA SE heads . Now just to swap them back on the flow bench to make sure they are balanced out . The numbers are of a stock TA SE head and some of a mild ported set
 

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I've been told a few minutes on the exhaust side on TA heads makes a huge improvement. Might be all you need.
 
TA Intimidator and Champion intake
Which way should i go?
this is my first set of Aluminum heads. T
I have a feeling the first thing someone is going to ask is how fast or how much?
Well the how much is obviously gone out the window 30k ago.
And the how fast is how "fast as the part will allow me to go?"
The cnc porting is as much as the heads cost.
the old fashioned way probably wouldn't be much different.
I havent seen any side by side flow numbers. Are there any?
Let me know of anybody who can port this setup i have and flow
it for me?
Im in N California.Im running a ported set of stock 8445s now
i want to compare what this setup does.no change to bottom.See what the trap
speed does.
At122mph I highly doubt your out of head even with a bad port job.turn the wick up on that 62/62 and keep your money in your pocket for when your ready to go bigger with the cam and turbo.
 
I am doing that now.love my 6262!
The cam and turbo upgrade will be later.

would it hurt to have too much head? hahaha!
seriously.
I know too much cam etc.
 
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are there ANY downsides to cncing heads ?
My car doesnt get very many miles at all.Ive had her for 7 years and have put maybe 3000 miles on her.
 
Head porting really doesn't matter as much on a turbo engine as it does on an N/A application.


Without supercharging you ONLY have 14.7PSI of pressure to work with.. Smoothing and blending, and matching and blah blah blah can really add up. Eliminating 1.5 pounds of pressure drop is 10% of what you have to work with. That's how you outrun a similar N/A engine...



Now in our case we have the same 14.7 AND however much boost we can run. For example, if you're at 25PSI of boost, that's 39.7 pounds of pressure going through the port. Small nuances and imperfections don't really mean that much when you're got a sledgehammer shoving air through the port (not to mention our air is compressed so it's smaller).


That being said the ported head engine will outrun a similar non ported engine..... ONLY if you're on the edge of maxing out the ports. If the ports aren't a restriction, then porting really don't do much of anything.

With what it cost to properly port a set of heads, 90% of the time less money can be spent elsewhere with better results.
 
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I don't believe you need to do a full CNC porting just some cleaning up of the short turns alil bowl work and some 30* back cuts on the valves will get the heads flowing well enough to notice a difference. Heads do make a difference though maybe not a crazy impact like in a NA motor as earl stated but they definitely will make a noticeable difference I'm my experience.
 
Running a good set of heads matters a lot if the turbo or some other aspect of the combo isn't a limiting factor. Even with a small turbo like a 6262 you can pick up big if you're not going all in with the the turbo. I've got hundreds of logs with different cars running different heads and different setups. Huge gains to be made when running the turbo at 50-90% of its max mass flow potential when the heads are better than some others. Once you start getting close to 100% with the turbo the heads will matter less and the turbo will be the limiting factor. If you want to see for yourself run good iron heads and good aluminum heads back to back up to the same drive pressure so the turbos are working equally as hard. You will find the engine with aluminum heads will make considerably more power until you close the gap on the turbo. At 30psi drive pressure on a 9:1 engine with a good set of aluminum heads you will see about 550whp (about 65lbs/min) on a 9:1 engine. At 45psi drive pressure you will see about 600whp (72-74lbs/min). Change nothing but the heads to good iron with and you will see about 500whp at 30psi drive pressure and still 600whp at 45psi drive pressure. About 50whp more at same drive pressure when not all in with the turbo. The turbo has to do less work to move the same amount of air. Fwiw a 62 will go 135-136@ 3600lbs all in.


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