Half BridgePort on stock twins
#1
brap brap brap
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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.
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#9
F'n Newbie...
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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!
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!
#12
Bubblicious DEF.
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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?
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?
#13
I won't let go
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.
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.
#14
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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.
#17
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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!!)
#19
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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
#22
Original Gangster/Rotary!
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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
I do agree that BNRs (run sequential) with a streetport is the hot ticket for a relatively cheap 400 rhwp setup
#23
Rotary Freak
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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 .
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 .
#24
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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?
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?
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.
#25
Rotary Freak
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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.
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.
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?