3rd Generation Specific (1993-2002) 1993-2002 Discussion including performance modifications and Technical Support Sections.
Sponsored by:

Half BridgePort on stock twins

Thread Tools
 
Search this Thread
 
Old 06-18-09, 06:29 PM
  #1  
brap brap brap

Thread Starter
iTrader: (12)
 
LERRY's Avatar
 
Join Date: Dec 2007
Location: SoCal
Posts: 254
Likes: 0
Received 0 Likes on 0 Posts
Half BridgePort on stock twins

well it's time for a rebuild or used motor and one of my options is a rebuilt HBP shortblock. I was wondering if anyone is running a hbp on stock twins, because i will be doing so on my 265ps 99spec twins. it won't be anything permanent, it will just take me more time to save up for a single now that i have to rebuild/buy another motor.
Old 06-19-09, 01:59 PM
  #2  
7th Heaven

iTrader: (9)
 
slpin's Avatar
 
Join Date: Nov 2004
Location: California
Posts: 3,654
Likes: 0
Received 1 Like on 1 Post
if it's not permanent then run it. if it is. you drive a fd not a fc
Old 06-19-09, 03:21 PM
  #3  
needs more track time

iTrader: (16)
 
gracer7-rx7's Avatar
 
Join Date: Mar 2006
Location: Bay Area CA
Posts: 9,181
Received 507 Likes on 349 Posts
I wouldn't do a bridge on a street car.
Old 06-19-09, 04:09 PM
  #4  
Adaptronic Distributor
RX7Club Vendor
iTrader: (12)
 
Turblown's Avatar
 
Join Date: Dec 2001
Location: Twin Cities, MN
Posts: 7,066
Received 91 Likes on 77 Posts
Originally Posted by gracer7-rx7
I wouldn't do a bridge on a street car.
Or on stock twins...
Old 06-19-09, 04:18 PM
  #5  
Mazzei Formula

iTrader: (6)
 
Monsterbox's Avatar
 
Join Date: Jun 2006
Location: Birmingham, Al
Posts: 3,020
Received 143 Likes on 69 Posts
is a small bridge really that disruptive into driveability? I've never driven one.
Old 06-19-09, 04:22 PM
  #6  
It's finally reliable

iTrader: (18)
 
MOBEONER's Avatar
 
Join Date: May 2004
Location: NEW YORK CITY
Posts: 3,511
Received 9 Likes on 7 Posts
My dad has a first gen full bridge.It idles high and its loud even with the racing beat exhaust.Its a perfect weekend cruise around car but i wouldn't use it as a daily.
Old 06-19-09, 05:02 PM
  #7  
Full Member

iTrader: (3)
 
zensokuracer001's Avatar
 
Join Date: May 2003
Location: charlotte
Posts: 212
Likes: 0
Received 0 Likes on 0 Posts
i have a hlaf bridge and stock twins also ran out of money and job, but it runs great do it no worries fun safe car and u can drive it
Old 06-19-09, 05:23 PM
  #8  
Sponsor
iTrader: (41)
 
IRPerformance's Avatar
 
Join Date: Apr 2003
Location: NJ
Posts: 11,347
Received 317 Likes on 190 Posts
Waste if time in my opinion. That and I see no reason to bridge a street car. You can make plenty of power with a properly done large street port.
Old 06-19-09, 06:10 PM
  #9  
F'n Newbie...

iTrader: (6)
 
fendamonky's Avatar
 
Join Date: Sep 2006
Location: Nokesville, Va
Posts: 3,928
Received 313 Likes on 228 Posts
Half Bridge + stock exhaust manifold = waste of time... You don't *need* a BP, or even a half-BP on any normal FD. Honestly, unless you're looking to win SERIOUS competition money (not show&shine) then why bother with BP on an FD???

You don't need massive porting to make good power on the FD... you just need to be smart with what you do, and find yourself a good tuner!
Old 06-19-09, 06:48 PM
  #10  
I won't let go


 
Railgun's Avatar
 
Join Date: Aug 2002
Location: Chi -> Maidstone
Posts: 3,861
Received 18 Likes on 13 Posts
A HBP on the street isn't all that bad. On twins though I don't see the point temporary or otherwise. Personally just do it right the first time.
Old 06-19-09, 08:27 PM
  #11  
Sponsor
iTrader: (41)
 
IRPerformance's Avatar
 
Join Date: Apr 2003
Location: NJ
Posts: 11,347
Received 317 Likes on 190 Posts
I guess everyones opinion is different but to me a bridgeported car on the street is just annoying. Its loud, wastes gas, runs like crap when cold, etc. For me its entertaining for about 5 min. Maybe I'm getting old...
Old 06-19-09, 08:37 PM
  #12  
Bubblicious DEF.

iTrader: (36)
 
muibubbles's Avatar
 
Join Date: May 2008
Location: 732
Posts: 4,265
Likes: 0
Received 4 Likes on 4 Posts
why is everyone so against s hbp on twins? if you hbp it dont you lose low end so wtih the twins wouldnt it make a nice powerband through out?

runs like crap in cold weather- wouldnt that be due to tune? no one drives the 7 in the winter anyways lol...

waste gas- isnt that only at idle due to higher rpms? i though u can maintain decent mpg as long as youre not on it.. from my understanding it just likes higher rpms, and fuels the same unless youre on it, and in that case it just goes downnnnnnnnn from there?

idk i know a guy who runs a hbp on his dd fc and he has no problems........

anymore input?
Old 06-19-09, 09:34 PM
  #13  
I won't let go


 
Railgun's Avatar
 
Join Date: Aug 2002
Location: Chi -> Maidstone
Posts: 3,861
Received 18 Likes on 13 Posts
Now that I'm on a real keyboard...

Ultimately to each their own. Whereas I can say I don't mind mine, I don't drive it daily. Then again, someone else could drive it daily and not mind as well. Then again, someone may not like it at all, daily driven or not. Point is you're going to get too many varying opinions on the subject. And to that end, they're all subjective opinions. And to nip the argument in the bud, yes, ALL of them.

If you want to weigh everyone's thoughts on the matter, it's not going to amount to squat until you get behind the wheel and drive it yourself for some period of time. You may like it for the first day, week or decade, then change your mind. You may not.

My personal experience is this, and needless to say, take it with a grain of salt.

I love it. Yes, it's loud, which I hate, but that's due to my current exhaust setup which I'm soon to change. No, around town it's not that bad to drive unless it's really slow stop and go. And in Chicago, that's a lot, but it's not THAT bad. My idle is 1200 at about 13 AFRs. The common point everyone will make is if you care about mileage, get another car. I don't care, so therefore I don't care what I get. It's not supposed to be economical.

Now that I've added my ISC back, it starts up wonderfully cold without hitting the gas at all now. It will stumble a little when cold but not die.

Yes, you lose low end power, but I had intentions of also tracking so that was a moot point for me. Though I think the gains outweigh the losses, though I have no idea how much power I'm making as I've yet to dyno it.

Long story short, drive one before you decide. It's my observation that most if not all 7 owners will let other 7 owners drive theirs. It's one of those things...

Oh, for the record, I'm running a T04R on the port. Everything I understand says the twins don't have enough breath for a HB, hence, scrap it. But I'm nowhere near the expert in that arena so...another grain of salt.
Old 06-19-09, 11:44 PM
  #14  
Senior Member

iTrader: (3)
 
DDagman's Avatar
 
Join Date: Aug 2005
Location: Foster city Ca
Posts: 334
Likes: 0
Received 0 Likes on 0 Posts
I run a large street port on my FD, and I love it. The idle is rough when I start it up in the mornings, but that maybe also because I'm not running a fuel pump. Its very loud, and idles pretty bad before its warm, so I think that going with a HBP is excessive. STick with a large street port if your running stock twins and are going to use is as a dd.
Old 06-20-09, 08:35 PM
  #15  
Bubblicious DEF.

iTrader: (36)
 
muibubbles's Avatar
 
Join Date: May 2008
Location: 732
Posts: 4,265
Likes: 0
Received 4 Likes on 4 Posts
uh ohh so hbp and 99 spec twins not looking too smart? hahahaha
Old 06-20-09, 10:43 PM
  #16  
Please somebody help!!!

iTrader: (1)
 
NissanConvert's Avatar
 
Join Date: Sep 2005
Location: Woodridge, IL
Posts: 1,442
Likes: 0
Received 0 Likes on 0 Posts
The twins couldn't match them. All of that port would be wasted as soon as it hit the stock manifold.
Old 06-20-09, 10:54 PM
  #17  
Lives on the Forum

iTrader: (5)
 
84stock's Avatar
 
Join Date: Apr 2003
Location: calgary
Posts: 5,537
Likes: 0
Received 9 Likes on 5 Posts
I've driven both a HBP and streetport with the same intake and exhaust (camden). The supercharger really tamed the idle and drew out a lot of midrange that it wouldn't ordinarily have. I like it, drove well and sounded great. Then......a bridge snapped off and went threw the motor (boom). Back to streetport and lov'in it now, soo sooooo driveable and smooth. I went for a ride in a singe turbo streetport fd that put 370rwhp on a mild tune, pulled amazingly hard (kills my car!!)
Old 06-20-09, 11:16 PM
  #18  
Bubblicious DEF.

iTrader: (36)
 
muibubbles's Avatar
 
Join Date: May 2008
Location: 732
Posts: 4,265
Likes: 0
Received 4 Likes on 4 Posts
wowww judging from what everyone is saying hbp and 99 is garbage... haha this should be fun...........
Old 06-20-09, 11:28 PM
  #19  
Lives on the Forum

iTrader: (5)
 
84stock's Avatar
 
Join Date: Apr 2003
Location: calgary
Posts: 5,537
Likes: 0
Received 9 Likes on 5 Posts
Not garbage, just different, just depends what you want. 450+ peaky high rev'in rwhp, or smooth streetable 370+rwhp with a wide powerband. I rode in a big hp hpb big turbo fc, it too was an impressive feeling when it all kicked in. Nothing compares to the idle of a bridgeport, again depends what you want. http://s222.photobucket.com/albums/d...hortbridge.flv
Old 06-21-09, 07:17 AM
  #20  
Please somebody help!!!

iTrader: (1)
 
NissanConvert's Avatar
 
Join Date: Sep 2005
Location: Woodridge, IL
Posts: 1,442
Likes: 0
Received 0 Likes on 0 Posts
If you want big power on twins i'd go with a street port and bnrs. If you want just a little more power over stock and better response then go with the '99's.
Old 06-21-09, 08:21 AM
  #21  
Lives on the Forum

iTrader: (8)
 
thewird's Avatar
 
Join Date: Oct 2006
Location: Toronto, Canada
Posts: 6,591
Likes: 0
Received 11 Likes on 11 Posts
Originally Posted by NissanConvert
If you want big power on twins i'd go with a street port and bnrs. If you want just a little more power over stock and better response then go with the '99's.
It's more then just a little over stock. With the right setup, you can make 100+ rwhp on pump gas then stock.

thewird
Old 06-21-09, 08:30 AM
  #22  
Original Gangster/Rotary!


iTrader: (213)
 
GoodfellaFD3S's Avatar
 
Join Date: Mar 2001
Location: FL-->NJ/NYC again!
Posts: 30,525
Received 538 Likes on 325 Posts
I think he means the 99 spec twins have the same power potential as stock twins, and I'd actually argue they don't. 99 spec twins don't stand up to 'high' boost (more than about 1 bar) repeated use as well as the usdm twins. All japanese tuners that I know of typically tune the 99 spec twins cars to 0.9 bar/13 psi for street use.

I do agree that BNRs (run sequential) with a streetport is the hot ticket for a relatively cheap 400 rhwp setup
Old 01-01-15, 11:56 AM
  #23  
Rotary Freak

iTrader: (5)
 
Tem120's Avatar
 
Join Date: Sep 2011
Location: Miami
Posts: 2,824
Likes: 0
Received 5 Likes on 5 Posts
what about when it comes to a track / streetable car .

The car is normally used for track / autocross / fun kinda driving .

and street driving to the events and sometimes for cruises.



Currently running on stock twins , BUt stock twins will be replaced with a small single TARGET power is 350-375 .

I know that the Stock ports are very capable of that power

BUT because I want to use a small single in order to keep good spool

My thoughts are with a half bridge would the improved Volumetric Efficiency make for a better more reliable , cooler running track car ?

Or would it still be better to just run a street port .
Old 01-01-15, 12:43 PM
  #24  
Moderator

iTrader: (3)
 
j9fd3s's Avatar
 
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,789
Received 2,570 Likes on 1,828 Posts
Originally Posted by muibubbles
why is everyone so against s hbp on twins? if you hbp it dont you lose low end so wtih the twins wouldnt it make a nice powerband through out?

runs like crap in cold weather- wouldnt that be due to tune? no one drives the 7 in the winter anyways lol...

waste gas- isnt that only at idle due to higher rpms? i though u can maintain decent mpg as long as youre not on it.. from my understanding it just likes higher rpms, and fuels the same unless youre on it, and in that case it just goes downnnnnnnnn from there?

idk i know a guy who runs a hbp on his dd fc and he has no problems........

anymore input?
the problem with the bridge port and twins is that you are making the engine more sensitive to back pressure, and then giving it a lot of backpressure. there is a real chance you will loose everywhere as the combination is not very ideal.

basically you will add a bunch of exhaust gasses into the intake, which lowers power and takes more fuel, without any big gain in airflow, because the turbo is still too small.

to take advantage of the bigger port, you also need a bigger turbo.
Old 01-01-15, 12:50 PM
  #25  
Rotary Freak

iTrader: (5)
 
Tem120's Avatar
 
Join Date: Sep 2011
Location: Miami
Posts: 2,824
Likes: 0
Received 5 Likes on 5 Posts
Originally Posted by j9fd3s
the problem with the bridge port and twins is that you are making the engine more sensitive to back pressure, and then giving it a lot of backpressure. there is a real chance you will loose everywhere as the combination is not very ideal.

basically you will add a bunch of exhaust gasses into the intake, which lowers power and takes more fuel, without any big gain in airflow, because the turbo is still too small.

to take advantage of the bigger port, you also need a bigger turbo.
yup I gathered that much , But the stock twins atleast for me are just a temporary solution

With the plan to swap in a small single later on , For quick spool , and good VE at higher RPM ( due to ports ) since that is where Smaller turbos kind of hurt on quic kspool , But lose power at higher RPM, I was wondeirng if I went with something like a half bridge would hte improved VE from the half bridge make up for the downfall of a smaller turbo .

would this be a good idea ?

or should I just say screw that . I can make my power goal of 350-375 easy on stock ports dont mess with it . deal with the loss of high end power . some other way .

Also does that extra back pressure not mean better spool?


Quick Reply: Half BridgePort on stock twins



All times are GMT -5. The time now is 08:18 AM.