2nd Generation Specific (1986-1992) 1986-1992 Discussion including performance modifications and technical support sections.

My N/A bridgeport

Thread Tools
 
Search this Thread
 
Old Oct 18, 2004 | 10:20 AM
  #1  
Kim's Avatar
Kim
Thread Starter
OBEY YOUR MAZDA
Tenured Member 20 Years
 
Joined: Oct 2002
Posts: 3,060
Likes: 2
From: Denmark
My N/A bridgeport

Sorry im too lazy to write it all over again

https://www.rx7club.com/showthread.php?t=359139
Reply
Old Oct 18, 2004 | 10:23 AM
  #2  
Kim's Avatar
Kim
Thread Starter
OBEY YOUR MAZDA
Tenured Member 20 Years
 
Joined: Oct 2002
Posts: 3,060
Likes: 2
From: Denmark
Opinions or suggestions are more than welcome
Reply
Old Oct 18, 2004 | 10:43 AM
  #3  
hugo20's Avatar
Senior Member
Tenured Member 05 Years
 
Joined: Oct 2003
Posts: 271
Likes: 0
From: Sherbrooke,QC,Canada
look TOO MUCH rought....
smooth it...
Reply
Old Oct 18, 2004 | 11:16 AM
  #4  
Kim's Avatar
Kim
Thread Starter
OBEY YOUR MAZDA
Tenured Member 20 Years
 
Joined: Oct 2002
Posts: 3,060
Likes: 2
From: Denmark
I will, im gonna work on them tonight.
Trying to make the extra ports flow a little better.
They are temporary pictures.
Reply
Old Oct 18, 2004 | 11:54 AM
  #5  
RotaryWeaponSE7EN's Avatar
Rotary Freak
Tenured Member 20 Years
iTrader: (6)
 
Joined: Dec 2001
Posts: 2,937
Likes: 3
From: Mission,KS
Nice, have fun w/ that man.
Reply
Old Oct 18, 2004 | 12:08 PM
  #6  
91mazdarx7's Avatar
Rotary Freak
Tenured Member: 20 Years
 
Joined: Mar 2004
Posts: 1,575
Likes: 0
From: pennsylvania
damn thats a big porting job looks nice though hope it all go's smooth when it go's in your car
Reply
Old Oct 18, 2004 | 12:09 PM
  #7  
nonameo's Avatar
**-P I drive a miata.
Tenured Member 05 Years
 
Joined: Jul 2002
Posts: 1,600
Likes: 0
From: albany, GA
you should really, really think about a custom intake manifold.
Reply
Old Oct 18, 2004 | 05:06 PM
  #8  
rotarygod's Avatar
Rotors still spinning
Tenured Member 20 Years
iTrader: (1)
 
Joined: Jul 2002
Posts: 4,181
Likes: 23
From: Houston
In my opinion you've gone far too crazy with the auxillary ports. They close way too late. They are also too large for the small amount of airflow through that small runner. Bigger is not always better. Far from it. As you already know, you definitely need to do alot of work to get those things smooth. A whole lot of work. You can also no longer use the stock ecu or intake manifold. Again, you will lose alot of power if you do.

As long as you are running a true dual exhaust on a bridgeport, you aren't making it's full power potential. You absolutely have to collect the exhaust once you get to a bridgeport or larger. Anyone who says otherwise has never done it and has no experience.
Reply
Old Oct 18, 2004 | 05:35 PM
  #9  
ddub's Avatar
i am legendary
Tenured Member 05 Years
 
Joined: Sep 2003
Posts: 8,478
Likes: 1
From: Kirkland, WA
I had that exact same concept planned in my mind, except no divider between the two ports and the bridge continuing the whole way down.
Reply
Old Oct 18, 2004 | 06:52 PM
  #10  
Falcoms's Avatar
kill it with BOOMSTICK!
Tenured Member: 20 Years
 
Joined: Mar 2004
Posts: 1,227
Likes: 0
From: McHenry, IL
Originally Posted by dDuB
I had that exact same concept planned in my mind, except no divider between the two ports and the bridge continuing the whole way down.
That would be rediculous for the street for 2 reasons

1: it would have NO bottom end torque
2: it would be a 10,000rpm engine abouts, depending on the size of the bridge


Also, as a minor note, it wouldn't idle below 1,500 rpm


Edit: Then again, for the track, ANYTHING GOES!!!!
Reply
Old Oct 18, 2004 | 07:03 PM
  #11  
ddub's Avatar
i am legendary
Tenured Member 05 Years
 
Joined: Sep 2003
Posts: 8,478
Likes: 1
From: Kirkland, WA
Originally Posted by Falcoms
That would be rediculous for the street for 2 reasons

1: it would have NO bottom end torque
2: it would be a 10,000rpm engine abouts, depending on the size of the bridge


Also, as a minor note, it wouldn't idle below 1,500 rpm


Edit: Then again, for the track, ANYTHING GOES!!!!
Your definition of street isn't everyones

3 window bearings, lightweight rotors, etc etc etc, all the mods to make it go to 10k and that port would be a fuuuuuuuuuuuuun car imo.

Who cares about low end torque, I don't have any of that now anyways

Some people might consider my car rediculous for the street. Solid diff/tranny/engine mounts, aluminum flywheel, and large streetported secondaries with NO divider (combined 2 ports) and medium streetport on the primary, no aux port actuators or sleeves. I have no problems driving this every day to and from school for 30+ minutes.

Last edited by ddub; Oct 18, 2004 at 07:06 PM.
Reply
Old Oct 18, 2004 | 07:28 PM
  #12  
Falcoms's Avatar
kill it with BOOMSTICK!
Tenured Member: 20 Years
 
Joined: Mar 2004
Posts: 1,227
Likes: 0
From: McHenry, IL
^ Okay, maybe I underestimated you. Personally, I think it'd be fun for me too, but the damn traffic where I live just kills it for me.
Reply
Old Oct 18, 2004 | 07:34 PM
  #13  
ddub's Avatar
i am legendary
Tenured Member 05 Years
 
Joined: Sep 2003
Posts: 8,478
Likes: 1
From: Kirkland, WA
Originally Posted by Falcoms
^ Okay, maybe I underestimated you. Personally, I think it'd be fun for me too, but the damn traffic where I live just kills it for me.


30+ minutes to school where 3 days a week its stop and go half the time UPHILL makes for an interesting time

But I got used to it quickly and it doesn't bother me anymore. I am very tolerable of "unstreetable" things I guess and can adapt quickly.
Reply
Old Oct 18, 2004 | 07:35 PM
  #14  
RotaryWeaponSE7EN's Avatar
Rotary Freak
Tenured Member 20 Years
iTrader: (6)
 
Joined: Dec 2001
Posts: 2,937
Likes: 3
From: Mission,KS
U both have good points. Depends on how u look at it.
Reply
Old Oct 18, 2004 | 08:53 PM
  #15  
Blade8r's Avatar
Full Member
Tenured Member 05 Years
 
Joined: Jul 2002
Posts: 136
Likes: 0
From: california
would it be a good idea to grab a stock motor half bridgeport it? i mean talking about adding a half bridge on it without porting the stock ports. would this be a worthwhile port on an n/a instead of doing a heavy streetport. would it be a good idea just run a half bridgeport in the streets? what would be the good and cons of having this setup. i personally would like a car with power all in the high end rpm's. but i would also like to be streetable as well. i would at very much least like my car to idle at 1k rpm minimum. but then again i don't want to have to attempt to reach for any power above 8.5k i really don't want to build my engine for a high rev but rather have it reach the stock limits.
Reply
Old Oct 18, 2004 | 09:27 PM
  #16  
Falcoms's Avatar
kill it with BOOMSTICK!
Tenured Member: 20 Years
 
Joined: Mar 2004
Posts: 1,227
Likes: 0
From: McHenry, IL
^ Sure, why wouldn't it be. Actually, a mild 1/2 bridge won't put your power band much over 8k. Idle could even be at or below 1k like you want. You could even probably get away with porting the stock ports if you keep the bridges mild. See, the reason idle is so much higher on bp or pp cars is because exhaust gas is being allowed to slip into the intake moreso as a stock port would. If you look at it, the port opens so much more in a bp then stock that it's stunning. As this is the case, you get tons of overlap from the exhaust and intake ports being open at the same time. This is why your idle is so much higher.

Now that that is explained, the reason a 1/2 is better then a full bridge is that the power is available much earlier in the power band. This means that you expand your power output over a lower rpm range then the full would. If you want to know about porting, go to http://home.iprimus.com.au/bluey3/portsPage/ports.htm or get the RX-7 performance handbook. The website is a good basic reference, but the book goes more in depth by far in the behavior of the engine and what exactly the porting effects. To fully understand it you should actually see an open engine with a stock port and one with a port job to see what happens exactly, then it will click. www.nopistons.com has a good section in their forum on porting, and they show some great pictures that will help you understand this mystical process more thoroughly.

sorry to ramble, but I'm tired. Good night all!
Reply
Old Oct 19, 2004 | 06:13 PM
  #17  
Rx7Boi's Avatar
Full Member
Tenured Member 15 Years
 
Joined: Mar 2001
Posts: 103
Likes: 0
From: Bay Area
Originally Posted by Falcoms
That would be rediculous for the street for 2 reasons

1: it would have NO bottom end torque
2: it would be a 10,000rpm engine abouts, depending on the size of the bridge


Also, as a minor note, it wouldn't idle below 1,500 rpm


Edit: Then again, for the track, ANYTHING GOES!!!!
Have you ever had a daily driven bridgeport?
how about anything over stock ports?
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
James Knox
Introduce yourself
5
Oct 22, 2015 05:08 PM
LongDuck
1st Generation Specific (1979-1985)
12
Oct 7, 2015 08:12 PM
rxlevi7
New Member RX-7 Technical
4
Sep 26, 2015 07:28 AM




All times are GMT -5. The time now is 11:16 AM.