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Half bridge port, who has one?

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Old 07-27-04, 05:02 PM
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Originally Posted by RX7WEEE
im no dorko your the dorko jk
Case and point...

LOOL!! I'm j/k!! hehe
Old 07-27-04, 05:05 PM
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you two **** need a room
Old 07-27-04, 05:06 PM
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Originally Posted by RX7WEEE
oh come on now it was just in fun!

but i know how u feel i have done it also... heard something then got told that it was totaly diff.

.......
Looking for someone to ride in the same boat as you, dorko? jk

Anyway, as far as this 0.5 bridgeporting goes I figure even if we were to get 50k out of it...Not my daily driver...at 4k miles a year that would be 12.5 years on a motor...Sounds ok to me
Old 07-27-04, 05:07 PM
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exactly david! i drive the car on friday, saturday, sometimes sunday, and sometimes a random evening
Old 07-27-04, 05:07 PM
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Originally Posted by 93BlackFD
you two **** need a room
LOL shaddup.

So what are the pros and cons? You mind outlining them for me plz?
Old 07-27-04, 05:10 PM
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Originally Posted by apneablue
Anyway, as far as this 0.5 bridgeporting goes I figure even if we were to get 50k out of it...Not my daily driver...at 4k miles a year that would be 12.5 years on a motor...Sounds ok to me
Very good point...
Old 07-27-04, 05:10 PM
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well, i will speak on all of these myths after i dyno the car...which will be soon, just waiting to get some more defi's in so i can have more data to bring back from the dyno

i'm the only one to run the half bridge w/ the twins consistantly ( i know of one other who did it for a while, but only because he was waiting on his single to come in)

i will get some figures for you
Old 07-27-04, 05:13 PM
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Originally Posted by 93BlackFD
well, i will speak on all of these myths after i dyno the car...which will be soon, just waiting to get some more defi's in so i can have more data to bring back from the dyno

i'm the only one to run the half bridge w/ the twins consistantly ( i know of one other who did it for a while, but only because he was waiting on his single to come in)

i will get some figures for you
Yea? Any reason why it isn't common to get a half bridge on twins?

Oh and I'm not pressing you for #s...just trying to see the logic behind it. Because ppl almost have no reservations about porting, but bridgeporting seems to be much rarer. Trying to see if it's something I should reconsider...
Old 07-27-04, 05:14 PM
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Sweet! thanks. yeah i mean if i only drive the car 5k a year with a 50k motor life thats still 10 years! i i have driven 16k in one year on the FD but it's my DD right now. i got my golf thats has taken over the DD FD
Old 07-27-04, 05:16 PM
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because of port flow, the twins are too small for a bridge, it's just physics

it's like putting a fat chick in a FD
Old 07-27-04, 05:20 PM
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Originally Posted by 93BlackFD
it's like putting a fat chick in a FD
LOL!!
Old 07-27-04, 05:46 PM
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Originally Posted by 93BlackFD
because of port flow, the twins are too small for a bridge, it's just physics

it's like putting a fat chick in a FD
Omfg
Old 07-27-04, 07:41 PM
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Will it be okay to run the twin's for a little bit untill i get my single on there? Maybe like the breaking time and another 1-2k miles?
Old 07-27-04, 07:44 PM
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Originally Posted by RX7WEEE
Will it be okay to run the twin's for a little bit untill i get my single on there? Maybe like the breaking time and another 1-2k miles?
It's not going to hurt anything....Just not an ideal setup.
Old 07-27-04, 08:07 PM
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yeah thats what i though. im just doing everything to get ready for the T78!

Anyone know of some good templates for porting?
Old 07-27-04, 08:29 PM
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why waste your time and $$ pulling everything apart twice. wait till you got everything ready and money for everything and do it right the first time. i think doing a bridge on twins is pointless. plus you'll have to tune twice which is expensive as well.
Old 07-27-04, 08:47 PM
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I can probably answer some of that question you have.

The original theory behind against b-port was that because of the excessive overlap, you'll lose alot of low end and mid range in forced induction applications. Also, they think that the back pressure will be too great to use for forced induction. This is very true for N/A applications. However as more and more people started to investigate/trial and error in forced induction, they find that the overlap actually helps with the spool up. The reason behind that is that the unburned fuel ignites at the turbo manifold causing it to kick harder for the next combustion cycle (more air). higher velocity at the intake plus higher velocity at the exhaust = more hp. To give you an example, a T88 turbo can get 10psi of boost at 3krpm running half-bridge while SP is around 4krpm.

not sure if that makes sense?





Originally Posted by FDNewbie
LOL...wrong on ALL of it? I coulda sworn there was even a hint of truth possible in SOME of it?

Thanks for clearing it up though. So lemme ask you this...what exactly are the benefits and downsides to a half bridgeport??

I don't care about gas mileage or higher idle....and you said low end power is good? So what are the downsides? How's engine life? etc?

Thanks
~Ramy
Old 07-27-04, 09:12 PM
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perfect sense
Old 07-27-04, 09:21 PM
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mmm interesting. Thanks for the explenation.
Old 07-27-04, 10:28 PM
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WOW that is great to know... that may change the decision on what turbo i want to go with.

The reason why I'm going to be rebuilding it now is because it has 123,000 ON THE ORIGINAL MOTOR!!!!!!!!!

And if it blows then the rotor houseings will most likely be totaled and I don't wanna shell out the money for new ones... That's single turbo money.
Old 07-27-04, 10:51 PM
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Originally Posted by pluto
not sure if that makes sense?
It made perfect sense. Faster spoolup time is always a plus, and who'll complain about more hp? hehe. And both you and 93blackFD have both said that the whole thing w/ no low end is something of the past. So I guess I'm still trying to figure out why most people do NOT go w/ bridgeports...there's gotta be some downsides to it, right? (bad gas mileage is a hallmark of the FD, so is an erratic idle, so ignore those). Also, are there any other benefits?

Thanks
~Ramy
Old 07-27-04, 11:36 PM
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Originally Posted by pluto
I can probably answer some of that question you have.

The original theory behind against b-port was that because of the excessive overlap, you'll lose alot of low end and mid range in forced induction applications. Also, they think that the back pressure will be too great to use for forced induction. This is very true for N/A applications. However as more and more people started to investigate/trial and error in forced induction, they find that the overlap actually helps with the spool up. The reason behind that is that the unburned fuel ignites at the turbo manifold causing it to kick harder for the next combustion cycle (more air). higher velocity at the intake plus higher velocity at the exhaust = more hp. To give you an example, a T88 turbo can get 10psi of boost at 3krpm running half-bridge while SP is around 4krpm.

not sure if that makes sense?
IIIITSSS AAALLLLLIIIIIVVEEEEEE! Hi Pluto
Old 07-27-04, 11:47 PM
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Originally Posted by FDNewbie
It made perfect sense. Faster spoolup time is always a plus, and who'll complain about more hp? hehe. And both you and 93blackFD have both said that the whole thing w/ no low end is something of the past. So I guess I'm still trying to figure out why most people do NOT go w/ bridgeports...there's gotta be some downsides to it, right? (bad gas mileage is a hallmark of the FD, so is an erratic idle, so ignore those). Also, are there any other benefits?

Thanks
~Ramy
bad gas mileage = carburated

most modern fuel systems can adapt to any conditions
Old 07-28-04, 12:08 AM
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Originally Posted by 93BlackFD
bad gas mileage = carburated

most modern fuel systems can adapt to any conditions
So no negatives whatsoever? lol. C'mon now...
Old 07-28-04, 12:10 AM
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i think a higher idle, shorter life span, harder to tune. are some of the reasons why people may not want one.


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