difference betwen porting and not porting
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Joined: Nov 2001
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From: Watertown, NY
difference betwen porting and not porting
yeah what will be the power difference with stock port and street port in a S4 engine with everything stock, even the turbo? 10, 25, 50 hp?
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WTB S5 N/A FC
Joined: Oct 2001
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From: College Station, Tx
Oh man. Part of me is surprised that none of the oldies have touched this one.
A port is like adding a cam for a rotary. By enlargening the intake ports on the secondary housings, it allows for more air to flow into the combustion chamber. In a simple streetport, the ports are just massaged to a larger diameter to allow for better/more flow at higher RPM (think like a cam, this shifts the power band right on a dyno sheet, but adds more power). I have seen guys getting 20-30 hp off a mild street port.
No, don't dump for a 4 port engine. It has 2 less ports. Which means that it flows less air. You can port any 13B, not just the 4 port engines.
For daily driven cars, the trade off for power vs. lifespan equates to a streetport to being the best option. A j-port, half/full bridge, or even a perp. port are BAD ideas on daily driven cars IMHO. Do a little research first before making any commitments to port jobs:
http://www.mazdarotary.net/porting.htm
A port is like adding a cam for a rotary. By enlargening the intake ports on the secondary housings, it allows for more air to flow into the combustion chamber. In a simple streetport, the ports are just massaged to a larger diameter to allow for better/more flow at higher RPM (think like a cam, this shifts the power band right on a dyno sheet, but adds more power). I have seen guys getting 20-30 hp off a mild street port.
No, don't dump for a 4 port engine. It has 2 less ports. Which means that it flows less air. You can port any 13B, not just the 4 port engines.
For daily driven cars, the trade off for power vs. lifespan equates to a streetport to being the best option. A j-port, half/full bridge, or even a perp. port are BAD ideas on daily driven cars IMHO. Do a little research first before making any commitments to port jobs:
http://www.mazdarotary.net/porting.htm
Displacement > Boost
Joined: Oct 2002
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From: Mississippi
Originally posted by rico05
Oh man. Part of me is surprised that none of the oldies have touched this one.
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Oh man. Part of me is surprised that none of the oldies have touched this one.
[/url]
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From: n
There is no one general answer for such a question.
For every different person you ask this question, you're probably going to get a different answer.
Porting non-turbos is different than porting turbos. People have different views on overlap (I try to minimize overlap).
In general a street port should increase power at least 10% easily.
Due to the increase in power, mileage typically increases.
With my car (1987 Turbo II), porting increased mileage by 1 to 2 mpg. Power increase was about 20hp at the wheels - car produces over 200hp at the wheels.
-Ted
For every different person you ask this question, you're probably going to get a different answer.
Porting non-turbos is different than porting turbos. People have different views on overlap (I try to minimize overlap).
In general a street port should increase power at least 10% easily.
Due to the increase in power, mileage typically increases.
With my car (1987 Turbo II), porting increased mileage by 1 to 2 mpg. Power increase was about 20hp at the wheels - car produces over 200hp at the wheels.
-Ted
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From: n
Older than Dirt
Joined: May 2003
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From: Parts Unknown
Originally posted by 88IntegraLS
I'm not an old member but it seems that those of us who have done porting and posted about it get tired of answering the same question. But you did well and took care of this week's porting question episode.
I'm not an old member but it seems that those of us who have done porting and posted about it get tired of answering the same question. But you did well and took care of this week's porting question episode.
Anyway to contribute here, Rico has provided solid info and Ted is right. i myself on N/A's try to limit the porting I do unless I see that the exhaust has been upgraded or will be soon. Otherwise, I feel like, why bother.
I came, I saw, I boosted.
Joined: Apr 2001
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From: Windsor, Ontario, Canada
To add-
Porting work won't increase gas consumption unless you are going to be spending a good amount of time with the pedal mashed- using the extra air flow/timing that the porting affords.
Technically, fuel consumption at idle will go up a bit as well, since the engine is drawing slightly less vacuum, and needs a bit more fuel to keep an idle (since the port velocity is decreased). But that's so negligable that it isn't even a factor.
Porting work won't increase gas consumption unless you are going to be spending a good amount of time with the pedal mashed- using the extra air flow/timing that the porting affords.
Technically, fuel consumption at idle will go up a bit as well, since the engine is drawing slightly less vacuum, and needs a bit more fuel to keep an idle (since the port velocity is decreased). But that's so negligable that it isn't even a factor.
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From: n
I was regularly seeing 25mpg+ on all freeway trips from Sacramento to Vegas when I moved a few years back. The actually MPG calculated to just under 28mpg, and a full tank would have easily hit 400 miles!
Ported motor, 4 x 720, Field SFC
-Ted
Ported motor, 4 x 720, Field SFC
-Ted
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Joined: May 2009
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From: curacao
Oh man. Part of me is surprised that none of the oldies have touched this one.
A port is like adding a cam for a rotary. By enlargening the intake ports on the secondary housings, it allows for more air to flow into the combustion chamber. In a simple streetport, the ports are just massaged to a larger diameter to allow for better/more flow at higher RPM (think like a cam, this shifts the power band right on a dyno sheet, but adds more power). I have seen guys getting 20-30 hp off a mild street port.
No, don't dump for a 4 port engine. It has 2 less ports. Which means that it flows less air. You can port any 13B, not just the 4 port engines.
For daily driven cars, the trade off for power vs. lifespan equates to a streetport to being the best option. A j-port, half/full bridge, or even a perp. port are BAD ideas on daily driven cars IMHO. Do a little research first before making any commitments to port jobs:
http://www.mazdarotary.net/porting.htm
A port is like adding a cam for a rotary. By enlargening the intake ports on the secondary housings, it allows for more air to flow into the combustion chamber. In a simple streetport, the ports are just massaged to a larger diameter to allow for better/more flow at higher RPM (think like a cam, this shifts the power band right on a dyno sheet, but adds more power). I have seen guys getting 20-30 hp off a mild street port.
No, don't dump for a 4 port engine. It has 2 less ports. Which means that it flows less air. You can port any 13B, not just the 4 port engines.
For daily driven cars, the trade off for power vs. lifespan equates to a streetport to being the best option. A j-port, half/full bridge, or even a perp. port are BAD ideas on daily driven cars IMHO. Do a little research first before making any commitments to port jobs:
http://www.mazdarotary.net/porting.htm
May I ask why exactly half bridge porting is a BAD idea for a daily driving car? is there a way to get the brap brap brap sound and still keep the car a good car for daily driving car? thank you for your time in advance
holy thread revival.
you were soooo close to finding the right thread.
if you search again there are a billion threads on the advantages/disadvantages of bridge ports and street ports
you were soooo close to finding the right thread.
if you search again there are a billion threads on the advantages/disadvantages of bridge ports and street ports
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