My porting pics with ito's street ports
08-21-2008, 11:52 PM
#1
Junior Member
Thread Starter
Join Date: Oct 2006
Posts: 16
Just got done porting my irons with judge itos porting templet. If any one has any advise i would love some coments... [attachment=44849:IMG_0379.jpg][attachment=44848:IMG_0384.jpg][attachment=44850:
IMG_0386.jpg][attachment=44851:IMG_0387.jpg][attachment=44852:IMG_0385.jpg]
IMG_0386.jpg][attachment=44851:IMG_0387.jpg][attachment=44852:IMG_0385.jpg]
08-24-2008, 04:04 PM
#3
Junior Member
Thread Starter
Join Date: Oct 2006
Posts: 16
Here is one of my exhaust ports, the other one i ported just the same... the shiny spots outside of the ports are just some scuffs from sanding. Can't feel any difference with your fingers so i don't think it should be a problem. Any coments would be great. First time porting an engine and first rebuild so this monday i will be putting it together. I will take pics and post them as it goes together...
[attachment=44853:IMG00050.jpg]
[attachment=44853:IMG00050.jpg]
08-26-2008, 08:09 AM
#5
Senior Member
Join Date: Jan 2002
Location: NJ USA
Posts: 1,915
ports look good, I could see you spend some time in the bowl. I could also see, you made a nice flow towards the upper part of the port. your going to get some good acceleration.. not bad at all. the more you practice, the better you will get at it..
08-26-2008, 01:17 PM
#6
Member
Join Date: Oct 2005
Posts: 57
Originally Posted by Judge Ito' post='906919' date='Aug 26 2008, 10:09 AM
ports look good, I could see you spend some time in the bowl. I could also see, you made a nice flow towards the upper part of the port. your going to get some good acceleration.. not bad at all. the more you practice, the better you will get at it..
Whats exactly the bowl ? can anyone show me in a picture?
09-07-2008, 03:59 PM
#7
Fabricator
Join Date: Jan 2004
Location: Central Ohio (Hebron) Zephyrhills Fla.
Posts: 1,322
Originally Posted by -xlr8planet-' post='906930' date='Aug 26 2008, 10:17 AM
Whats exactly the bowl ? can anyone show me in a picture?
The port face, controls timing and it is the opening decribed by the porting mask. The bowl connects the runner to the port face.
Generally the bowl volume is too big in stock trim, so no material is removed. Just a shine up.
http://home.earthlink.net/~mmc1919/venturi.html
Here is a link to the Bernoulli web site with an animation you can manipulate to form various venturi and see the outcome. You can move the yellow blocks up and down and left and right, to form any number of shapes. Below the picture is a set of graphs showing the outcomes of you shapes.
Now, make a big wide bowl shape on the end of a runner. What happened?
The rule is that a velocity increase, produces a pressure decrease. And a velocity decrease produces a pressure increase.
The object of course is to get the maximum amount of mixture (mass) into the chamber per each intake event.
You can think of this operation as a sausage machine forcing sausage into the chamber, and the rotor cutting the sausage into lengths. So you want the longest links possible, right?
What to do? For any RPM you want to test at, you want the very highest velocity. That way more sausage will get past the rotor before it is cut off. The longest links.
So, the highest velocity wins. Now note that when you constrict the runner, the velocity goes up, and when it is made bigger the velocity slows. But the high velocity is only needed at the port face where the cutting will happen. And the stock rotary has too much volume in the bowl right where you want less volume, Mazda gives you more volume. So some folks fill in some of the bowl volume with a steel filled epoxy. Of course if the epoxy comes off, the engine is gone.
High velocity generates high drag along the runner walls. Drag increases at the cube of velocity. So a runner that is of a constant cross section (constant velocity) generates the least drag.
Any time you increase or decrease the velocity of a flowing gas, you remove energy. If you increase or decrease the temperature of a flowing gas you change its energy. Any time you turn a flowing gas you remove energy. Like the 90 degree turn into the chamber.
In general this applies to NA engines. Tubo charged engines are very different.
Lynn E. Hanover
09-10-2008, 10:03 PM
#8
Member
Join Date: Oct 2005
Posts: 57
Originally Posted by Lynn E. Hanover' post='907503' date='Sep 7 2008, 05:59 PM
The port face, controls timing and it is the opening decribed by the porting mask. The bowl connects the runner to the port face.
Generally the bowl volume is too big in stock trim, so no material is removed. Just a shine up.
http://home.earthlink.net/~mmc1919/venturi.html
Here is a link to the Bernoulli web site with an animation you can manipulate to form various venturi and see the outcome. You can move the yellow blocks up and down and left and right, to form any number of shapes. Below the picture is a set of graphs showing the outcomes of you shapes.
Now, make a big wide bowl shape on the end of a runner. What happened?
The rule is that a velocity increase, produces a pressure decrease. And a velocity decrease produces a pressure increase.
The object of course is to get the maximum amount of mixture (mass) into the chamber per each intake event.
You can think of this operation as a sausage machine forcing sausage into the chamber, and the rotor cutting the sausage into lengths. So you want the longest links possible, right?
What to do? For any RPM you want to test at, you want the very highest velocity. That way more sausage will get past the rotor before it is cut off. The longest links.
So, the highest velocity wins. Now note that when you constrict the runner, the velocity goes up, and when it is made bigger the velocity slows. But the high velocity is only needed at the port face where the cutting will happen. And the stock rotary has too much volume in the bowl right where you want less volume, Mazda gives you more volume. So some folks fill in some of the bowl volume with a steel filled epoxy. Of course if the epoxy comes off, the engine is gone.
High velocity generates high drag along the runner walls. Drag increases at the cube of velocity. So a runner that is of a constant cross section (constant velocity) generates the least drag.
Any time you increase or decrease the velocity of a flowing gas, you remove energy. If you increase or decrease the temperature of a flowing gas you change its energy. Any time you turn a flowing gas you remove energy. Like the 90 degree turn into the chamber.
In general this applies to NA engines. Tubo charged engines are very different.
Lynn E. Hanover
Generally the bowl volume is too big in stock trim, so no material is removed. Just a shine up.
http://home.earthlink.net/~mmc1919/venturi.html
Here is a link to the Bernoulli web site with an animation you can manipulate to form various venturi and see the outcome. You can move the yellow blocks up and down and left and right, to form any number of shapes. Below the picture is a set of graphs showing the outcomes of you shapes.
Now, make a big wide bowl shape on the end of a runner. What happened?
The rule is that a velocity increase, produces a pressure decrease. And a velocity decrease produces a pressure increase.
The object of course is to get the maximum amount of mixture (mass) into the chamber per each intake event.
You can think of this operation as a sausage machine forcing sausage into the chamber, and the rotor cutting the sausage into lengths. So you want the longest links possible, right?
What to do? For any RPM you want to test at, you want the very highest velocity. That way more sausage will get past the rotor before it is cut off. The longest links.
So, the highest velocity wins. Now note that when you constrict the runner, the velocity goes up, and when it is made bigger the velocity slows. But the high velocity is only needed at the port face where the cutting will happen. And the stock rotary has too much volume in the bowl right where you want less volume, Mazda gives you more volume. So some folks fill in some of the bowl volume with a steel filled epoxy. Of course if the epoxy comes off, the engine is gone.
High velocity generates high drag along the runner walls. Drag increases at the cube of velocity. So a runner that is of a constant cross section (constant velocity) generates the least drag.
Any time you increase or decrease the velocity of a flowing gas, you remove energy. If you increase or decrease the temperature of a flowing gas you change its energy. Any time you turn a flowing gas you remove energy. Like the 90 degree turn into the chamber.
In general this applies to NA engines. Tubo charged engines are very different.
Lynn E. Hanover
Thanks a lot for taking the time to explain this.
The pipe demo helped too
Im not a brave man, so I will not fill the bowl with epoxi
Thanks again
10-03-2008, 02:03 AM
#10
Junior Member
Join Date: Sep 2008
Location: lexington, nc
Posts: 18
Originally Posted by Lynn E. Hanover' post='907503' date='Sep 7 2008, 04:59 PM
The port face, controls timing and it is the opening decribed by the porting mask. The bowl connects the runner to the port face.
Generally the bowl volume is too big in stock trim, so no material is removed. Just a shine up.
http://home.earthlink.net/~mmc1919/venturi.html
Here is a link to the Bernoulli web site with an animation you can manipulate to form various venturi and see the outcome. You can move the yellow blocks up and down and left and right, to form any number of shapes. Below the picture is a set of graphs showing the outcomes of you shapes.
Now, make a big wide bowl shape on the end of a runner. What happened?
The rule is that a velocity increase, produces a pressure decrease. And a velocity decrease produces a pressure increase.
The object of course is to get the maximum amount of mixture (mass) into the chamber per each intake event.
You can think of this operation as a sausage machine forcing sausage into the chamber, and the rotor cutting the sausage into lengths. So you want the longest links possible, right?
What to do? For any RPM you want to test at, you want the very highest velocity. That way more sausage will get past the rotor before it is cut off. The longest links.
So, the highest velocity wins. Now note that when you constrict the runner, the velocity goes up, and when it is made bigger the velocity slows. But the high velocity is only needed at the port face where the cutting will happen. And the stock rotary has too much volume in the bowl right where you want less volume, Mazda gives you more volume. So some folks fill in some of the bowl volume with a steel filled epoxy. Of course if the epoxy comes off, the engine is gone.
High velocity generates high drag along the runner walls. Drag increases at the cube of velocity. So a runner that is of a constant cross section (constant velocity) generates the least drag.
Any time you increase or decrease the velocity of a flowing gas, you remove energy. If you increase or decrease the temperature of a flowing gas you change its energy. Any time you turn a flowing gas you remove energy. Like the 90 degree turn into the chamber.
In general this applies to NA engines. Tubo charged engines are very different.
Lynn E. Hanover
Generally the bowl volume is too big in stock trim, so no material is removed. Just a shine up.
http://home.earthlink.net/~mmc1919/venturi.html
Here is a link to the Bernoulli web site with an animation you can manipulate to form various venturi and see the outcome. You can move the yellow blocks up and down and left and right, to form any number of shapes. Below the picture is a set of graphs showing the outcomes of you shapes.
Now, make a big wide bowl shape on the end of a runner. What happened?
The rule is that a velocity increase, produces a pressure decrease. And a velocity decrease produces a pressure increase.
The object of course is to get the maximum amount of mixture (mass) into the chamber per each intake event.
You can think of this operation as a sausage machine forcing sausage into the chamber, and the rotor cutting the sausage into lengths. So you want the longest links possible, right?
What to do? For any RPM you want to test at, you want the very highest velocity. That way more sausage will get past the rotor before it is cut off. The longest links.
So, the highest velocity wins. Now note that when you constrict the runner, the velocity goes up, and when it is made bigger the velocity slows. But the high velocity is only needed at the port face where the cutting will happen. And the stock rotary has too much volume in the bowl right where you want less volume, Mazda gives you more volume. So some folks fill in some of the bowl volume with a steel filled epoxy. Of course if the epoxy comes off, the engine is gone.
High velocity generates high drag along the runner walls. Drag increases at the cube of velocity. So a runner that is of a constant cross section (constant velocity) generates the least drag.
Any time you increase or decrease the velocity of a flowing gas, you remove energy. If you increase or decrease the temperature of a flowing gas you change its energy. Any time you turn a flowing gas you remove energy. Like the 90 degree turn into the chamber.
In general this applies to NA engines. Tubo charged engines are very different.
Lynn E. Hanover
hi Lynn,
would this mean that you would want your runners to be really thin, i.e. the stock size? It seems that you would want your runners stock and your port face, where you do your cutting, just large enough to get better timing, with a little shaping of the bowl to lessen the severity of the 90 degree bend. But, it seems that, from all of the porting pictures i've seen, everyone enlarges the runner as much as possible.