Port and Polish or Intake Manifold
So i just dropped my motor off to get it rebuilt since it popped a head gasket. And I'm wondering what is the better bang for the buck porting and polishing the heads or a Kinetix manifold? The car will be N/A until i get a Blower or Turbo.
Engine
Eagle Rods
Weisco 11:1 Pistons
BC Stage 2 cams
Long Tubes
5/16" Plenum Spacer
HKS replica Exhaust.
7200 redline
I have read that the Kinetix manifold will actually lose power on a NA set up and really shines on a F/I set up. But its a very well known fact that our stock set up really sucks, and gets heat soaked quickly. The Kinetix manifold resists the heat way better and the airflow is a lot more even.
I don't remember where i saw it but they compared stock DE, Rev-up, and Ported DE heads. The Ported DE head were only Slightly better than the Rev-up heads.
So can someone smarter than me help?
Engine
Eagle Rods
Weisco 11:1 Pistons
BC Stage 2 cams
Long Tubes
5/16" Plenum Spacer
HKS replica Exhaust.
7200 redline
I have read that the Kinetix manifold will actually lose power on a NA set up and really shines on a F/I set up. But its a very well known fact that our stock set up really sucks, and gets heat soaked quickly. The Kinetix manifold resists the heat way better and the airflow is a lot more even.
I don't remember where i saw it but they compared stock DE, Rev-up, and Ported DE heads. The Ported DE head were only Slightly better than the Rev-up heads.
So can someone smarter than me help?
Last edited by Conway_160; Aug 29, 2017 at 04:52 PM.
I lied it DE hs HR heads
http://www.onpointdyno.com/2013/03/v...-de-head-flow/
It equates to Roughly 25CFM improvement.
http://www.onpointdyno.com/2013/03/v...-de-head-flow/
It equates to Roughly 25CFM improvement.
Last edited by Conway_160; Aug 29, 2017 at 02:26 PM.
just stick with your OEM manifold ... spend your money and energy on getting your engine up and running, then add your turbo/supercharger, then worry about the small stuff...like an intake.
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Just as an added datapoint, porting - by itself - may offer a small benefit for a street driven car; however, so small that it's almost not worth doing. Porting AND polishing on a street driven car IS a waste of money. As a matter of fact, doing so may actually hurt performance due to a measured disruption of air flow. (For info on this, read up on "laminar versus turbulent flow".)
Conversely, in a race/high rpm application, there are pronounced benefits to port and polish BUT.... just porting to gasket match (for the sake of porting) and/or polishing along with it isn't optimal either.
To properly do it RIGHT, you (or the machine shop) MUST use a flow bench to determine whether or not there's a good reason to do it. Some heads already have maximized flow configurations (shape, length, size, etc.) of their ports; others not so much. And in the latter, ports may even require re-shaping - which could mean adding head material in places there wasn't anything before in order to effectively reshape the port.
I could go on and on (re: cam profiles, piston configuration, etc); but suffice to say that P&P isn't something to say, "Sure, go ahead and do it." in a casual manner as if responding to "do you want fries with that burger?" It's a huge investment in something that will offer little practical benefit - on the street - unless the science is applied to it before the actual grinder goes in.
I've personally wasted a lot of time and money on these procedures; enough to know a little better. Groan.... if I'da spent that money on MORE LAP TIME than hardware, I mighta finished on the podium more than once. Hahahahaha.
Conversely, in a race/high rpm application, there are pronounced benefits to port and polish BUT.... just porting to gasket match (for the sake of porting) and/or polishing along with it isn't optimal either.
To properly do it RIGHT, you (or the machine shop) MUST use a flow bench to determine whether or not there's a good reason to do it. Some heads already have maximized flow configurations (shape, length, size, etc.) of their ports; others not so much. And in the latter, ports may even require re-shaping - which could mean adding head material in places there wasn't anything before in order to effectively reshape the port.
I could go on and on (re: cam profiles, piston configuration, etc); but suffice to say that P&P isn't something to say, "Sure, go ahead and do it." in a casual manner as if responding to "do you want fries with that burger?" It's a huge investment in something that will offer little practical benefit - on the street - unless the science is applied to it before the actual grinder goes in.
I've personally wasted a lot of time and money on these procedures; enough to know a little better. Groan.... if I'da spent that money on MORE LAP TIME than hardware, I mighta finished on the podium more than once. Hahahahaha.
Last edited by MicVelo; Aug 30, 2017 at 08:02 AM.
Just as an added datapoint, porting - by itself - may offer a small benefit for a street driven car; however, so small that it's almost not worth doing. Porting AND polishing on a street driven car IS a waste of money. As a matter of fact, doing so may actually hurt performance due to a measured disruption of air flow. (For info on this, read up on "laminar versus turbulent flow".)
Conversely, in a race/high rpm application, there are pronounced benefits to port and polish BUT.... just porting to gasket match (for the sake of porting) and/or polishing along with it isn't optimal either.
To properly do it RIGHT, you (or the machine shop) MUST use a flow bench to determine whether or not there's a good reason to do it. Some heads already have maximized flow configurations (shape, length, size, etc.) of their ports; others not so much. And in the latter, ports may even require re-shaping - which could mean adding head material in places there wasn't anything before in order to effectively reshape the port.
I could go on and on (re: cam profiles, piston configuration, etc); but suffice to say that P&P isn't something to say, "Sure, go ahead and do it." in a casual manner as if responding to "do you want fries with that burger?" It's a huge investment in something that will offer little practical benefit - on the street - unless the science is applied to it before the actual grinder goes in.
I've personally wasted a lot of time and money on these procedures; enough to know a little better. Groan.... if I'da spent that money on MORE LAP TIME than hardware, I mighta finished on the podium more than once. Hahahahaha.
Conversely, in a race/high rpm application, there are pronounced benefits to port and polish BUT.... just porting to gasket match (for the sake of porting) and/or polishing along with it isn't optimal either.
To properly do it RIGHT, you (or the machine shop) MUST use a flow bench to determine whether or not there's a good reason to do it. Some heads already have maximized flow configurations (shape, length, size, etc.) of their ports; others not so much. And in the latter, ports may even require re-shaping - which could mean adding head material in places there wasn't anything before in order to effectively reshape the port.
I could go on and on (re: cam profiles, piston configuration, etc); but suffice to say that P&P isn't something to say, "Sure, go ahead and do it." in a casual manner as if responding to "do you want fries with that burger?" It's a huge investment in something that will offer little practical benefit - on the street - unless the science is applied to it before the actual grinder goes in.
I've personally wasted a lot of time and money on these procedures; enough to know a little better. Groan.... if I'da spent that money on MORE LAP TIME than hardware, I mighta finished on the podium more than once. Hahahahaha.
So what your saying is I just waisted all this time on nothing?
Thanks a lot.
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Yes.
Hahaha.... nawww, the original post asked about head porting, not the manifold. Although, here's the test: put that sucker on and show us the before/after dyno.
Again, if you want to know if this helps or not, choose your RPM range then read up on the aforementioned fluid flow characteristics. Won't apply much here as there's no fuel flowing through but it still applies to air flow, which behaves in the same manner.
Think "golf ball".
Haha well I guess ill take your word for it and just not do it... We all know if I actually already did this it would have been thoroughly documented in another post.
The thought did cross my mind though.
The thought did cross my mind though.
Just as an added datapoint, porting - by itself - may offer a small benefit for a street driven car; however, so small that it's almost not worth doing. Porting AND polishing on a street driven car IS a waste of money. As a matter of fact, doing so may actually hurt performance due to a measured disruption of air flow. (For info on this, read up on "laminar versus turbulent flow".)
Conversely, in a race/high rpm application, there are pronounced benefits to port and polish BUT.... just porting to gasket match (for the sake of porting) and/or polishing along with it isn't optimal either.
To properly do it RIGHT, you (or the machine shop) MUST use a flow bench to determine whether or not there's a good reason to do it. Some heads already have maximized flow configurations (shape, length, size, etc.) of their ports; others not so much. And in the latter, ports may even require re-shaping - which could mean adding head material in places there wasn't anything before in order to effectively reshape the port.
I could go on and on (re: cam profiles, piston configuration, etc); but suffice to say that P&P isn't something to say, "Sure, go ahead and do it." in a casual manner as if responding to "do you want fries with that burger?" It's a huge investment in something that will offer little practical benefit - on the street - unless the science is applied to it before the actual grinder goes in.
I've personally wasted a lot of time and money on these procedures; enough to know a little better. Groan.... if I'da spent that money on MORE LAP TIME than hardware, I mighta finished on the podium more than once. Hahahahaha.
Conversely, in a race/high rpm application, there are pronounced benefits to port and polish BUT.... just porting to gasket match (for the sake of porting) and/or polishing along with it isn't optimal either.
To properly do it RIGHT, you (or the machine shop) MUST use a flow bench to determine whether or not there's a good reason to do it. Some heads already have maximized flow configurations (shape, length, size, etc.) of their ports; others not so much. And in the latter, ports may even require re-shaping - which could mean adding head material in places there wasn't anything before in order to effectively reshape the port.
I could go on and on (re: cam profiles, piston configuration, etc); but suffice to say that P&P isn't something to say, "Sure, go ahead and do it." in a casual manner as if responding to "do you want fries with that burger?" It's a huge investment in something that will offer little practical benefit - on the street - unless the science is applied to it before the actual grinder goes in.
I've personally wasted a lot of time and money on these procedures; enough to know a little better. Groan.... if I'da spent that money on MORE LAP TIME than hardware, I mighta finished on the podium more than once. Hahahahaha.





