Bridgeport vs. 1/2 Bridge ?
11-05-06, 02:34 PM
#151
Engine, Not Motor
iTrader: (1)
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,789
Likes: 0
Received 108 Likes
on
91 Posts
So I've been driving my car for two weeks now, and it's great.
The idle scares away all the ricers. Women and children cover their ears, old men shake their fists and dogs cower in fear...
The car will cruise all day at 2K RPM withou much drama and there's absolutely no lack at all of low end. With the stock turbo, it will spool easily at 2K under medium throttle. I'm still working out the injector staging with the 720cc/1600CC combination so above 4K it's a bit (OK, stupidly rich) rich but after 4K at light throttle (keeping only the primaries online) the car just comes alive....
The idle scares away all the ricers. Women and children cover their ears, old men shake their fists and dogs cower in fear...
The car will cruise all day at 2K RPM withou much drama and there's absolutely no lack at all of low end. With the stock turbo, it will spool easily at 2K under medium throttle. I'm still working out the injector staging with the 720cc/1600CC combination so above 4K it's a bit (OK, stupidly rich) rich but after 4K at light throttle (keeping only the primaries online) the car just comes alive....
08-01-07, 01:16 PM
#152
Senior Member
Join Date: Jan 2005
Location: SLC, Utah
Posts: 257
Likes: 0
Received 0 Likes
on
0 Posts
so i think im convinced. after reading this im thinking a streetport. now i need to do some finding on streetports and find out which would best fit me. thanks everyone
01-04-10, 02:15 PM
#155
Engine, Not Motor
iTrader: (1)
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,789
Likes: 0
Received 108 Likes
on
91 Posts
Not sure what you mean. My car has been running for a long time since I commented in this thread. I do wish that I had ported down more with the bridge instead of keeping it artificially small in the idea that I would make valve-controlled bridgeports (which I didn't and don't plan on) but I can't complain at all about how it turned out. Over 400 RWHP on low boost, 500 or so at 16 PSI.
To anyone doing a bridgeport I would suggest a half bridge (secondaries only) or a full bridge. I honestly don't see the point anymore in half-assing a bridgeport. Nothing wrong with half bridge of course, but a full bridge makes more power with only a slight decline in idle quality, mileage and vacuum compared to a half.
To anyone doing a bridgeport I would suggest a half bridge (secondaries only) or a full bridge. I honestly don't see the point anymore in half-assing a bridgeport. Nothing wrong with half bridge of course, but a full bridge makes more power with only a slight decline in idle quality, mileage and vacuum compared to a half.
01-09-10, 11:00 AM
#158
Engine, Not Motor
iTrader: (1)
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,789
Likes: 0
Received 108 Likes
on
91 Posts
With 6 port irons, the aux ports will need to be left open. The sleeve will need to be removed. The bridge will extend a little into each aux port. Start with a 4 port bridgeporting template as a guide.
01-10-10, 10:49 AM
#160
01-10-10, 02:30 PM
#161
Regarding spoolup, has anyone actually done some true, no BS back to back tests with different ports?
In the import scene (Rotary and Piston) all I hear is people saying/thinking that bigger ports, more duration, more overlap, etc HELPS spoolup, and its due to more gas getting in and out, but from countless turbo cars ive played with over the years (all piston, hence the question), this is complete BS, and though maybe they will spool faster once actually in the boost threshold, the boot threshold (and powerband in general) is actually raised with bigger ports and more duration/overlap, and less torque too.
Look any any turbo race car, Offy Indy engines are a good example, very little need for low power, and even at the level where they was pushing around 1000bhp, the cams were what most JDM tunng people call "stage1" mild cams, about 264 duration. Personally, coming from a non-JDM turbo tuning background, id call 264 pretty fookin hardcor on a turbo car.
And because of all this, the Bridgeports help spool thing is something ive always been mega scepitcal of, and its true or false depends who you listen to.
Soo... Is there any true back to back testing on this?
In the import scene (Rotary and Piston) all I hear is people saying/thinking that bigger ports, more duration, more overlap, etc HELPS spoolup, and its due to more gas getting in and out, but from countless turbo cars ive played with over the years (all piston, hence the question), this is complete BS, and though maybe they will spool faster once actually in the boost threshold, the boot threshold (and powerband in general) is actually raised with bigger ports and more duration/overlap, and less torque too.
Look any any turbo race car, Offy Indy engines are a good example, very little need for low power, and even at the level where they was pushing around 1000bhp, the cams were what most JDM tunng people call "stage1" mild cams, about 264 duration. Personally, coming from a non-JDM turbo tuning background, id call 264 pretty fookin hardcor on a turbo car.
And because of all this, the Bridgeports help spool thing is something ive always been mega scepitcal of, and its true or false depends who you listen to.
Soo... Is there any true back to back testing on this?
01-11-10, 04:10 PM
#162
Engine, Not Motor
iTrader: (1)
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,789
Likes: 0
Received 108 Likes
on
91 Posts
Bridgeports do indeed make a massive difference. The short technical explanation is that the misfiring at lower RPMs caused by the dilution of the intake air/fuel causes higher pressure chambers, in addition to more afterburn. Both those create a more powerful exhaust pulse.
I have run the same turbo on a stock port vs. a bridgeported car. Night and day difference.
Anyway, here are the pictures of a bridgeported 6 port iron I promised. I took them with my Blackberry (forgot my camera) so excuse the quality. I RB 4 port bridgeport timings and just ran the bridge above both the secondary and aux intake ports.
I have run the same turbo on a stock port vs. a bridgeported car. Night and day difference.
Anyway, here are the pictures of a bridgeported 6 port iron I promised. I took them with my Blackberry (forgot my camera) so excuse the quality. I RB 4 port bridgeport timings and just ran the bridge above both the secondary and aux intake ports.
01-12-10, 09:36 AM
#164
Engine, Not Motor
iTrader: (1)
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,789
Likes: 0
Received 108 Likes
on
91 Posts
The engine I posted is a half bridge engine, so only the end irons are bridged. It's actually a pretty healthy bridge. It cuts into the housing about 1.5MM. First time I've had to notch housings. 
07-27-10, 01:46 AM
#167
just curious.
07-27-10, 08:47 AM
#168
Engine, Not Motor
iTrader: (1)
Join Date: Feb 2001
Location: London, Ontario, Canada
Posts: 29,789
Likes: 0
Received 108 Likes
on
91 Posts
You'd basically end up with an engine that has all the bad characteristics of a full-bridge but none of the power. The primaries flow only a fraction of the secondaries.
07-27-10, 12:33 PM
#170
Junior Member
Join Date: Jul 2010
Location: Reading, Pa
Posts: 9
Likes: 0
Received 0 Likes
on
0 Posts
When i rebuilt mine, I went with a full bridge, with my turbo setup making full power about 6800-9000rpm. And you can't beat the sound. As far as drive ability, its not much fun stop and go and I find that at a cruise it really likes to keep its revs above 3,000. Also fuel consumption is much higher since I bridged it.
09-08-10, 11:40 AM
#172
I am understanding that you are all talking about bridging with turbos but what about an N/A car? I have a s4 that ive been looking into porting for sometime but this is the best info i have found. Yet still nothing is being said much as to how a n/a would go with it. What type of things would i need to have in order to do a HBP? would 770 injectors work?
10-28-10, 09:18 PM
#173
im reviving... this thread got so off topic i began to skim... too much bp vs sp...
i use to have a hbp and the motor went.. now the next motor im contemplating doing a full bridge... what are the MAIN differences? ive spoke to someone on the forum (cant remember who) but hes had both and said drivability is no different...
when you guys say "half *** hbp" what does that mean? being conservative in the porting or dont half *** it just go full bridge?
i use to have a hbp and the motor went.. now the next motor im contemplating doing a full bridge... what are the MAIN differences? ive spoke to someone on the forum (cant remember who) but hes had both and said drivability is no different...
when you guys say "half *** hbp" what does that mean? being conservative in the porting or dont half *** it just go full bridge?
10-28-10, 11:55 PM
#174
s4 Pride
iTrader: (19)
Join Date: Oct 2006
Location: Rancho Cucamonga, CA
Posts: 3,350
Likes: 0
Received 3 Likes
on
3 Posts
im reviving... this thread got so off topic i began to skim... too much bp vs sp...
i use to have a hbp and the motor went.. now the next motor im contemplating doing a full bridge... what are the MAIN differences? ive spoke to someone on the forum (cant remember who) but hes had both and said drivability is no different...
when you guys say "half *** hbp" what does that mean? being conservative in the porting or dont half *** it just go full bridge?
i use to have a hbp and the motor went.. now the next motor im contemplating doing a full bridge... what are the MAIN differences? ive spoke to someone on the forum (cant remember who) but hes had both and said drivability is no different...
when you guys say "half *** hbp" what does that mean? being conservative in the porting or dont half *** it just go full bridge?
04-08-11, 07:35 AM
#175
Sorry to bring this back, but took me several hours to read this thread, and there is an amplitude of useful information on it and I'd like to add whatever I can.
First of all for anyone still considering a halfie or full BP, I have witnessed BDC's HBP on an FC here in Charlotte several years ago. It didn't matter what type of car meet we went to, when he showed up literally everyone's attention would be directed to the 'brap, brap, brap'... I have a vid, put you're not aloud to post **** on this forum.
Not only did the sound entice you, but when I lined up with him on the highway in my lightly modded tii and got pulled harder than any car I've ever raced (and he was still only running 9psi), I was sold (in fact BDC you will be gettin an email from me in the coming days). He would drive that FC daily without problems, the idle was loud, but not unbearable at all, (not as loud as my exhaust system with stock ports now if it idled over 1000rpms) and the entire car would rumble as it idled much like a cammed v8 would. And as others have stated previously, it pulled forever.
Personally, I wouldn't want one for a DD. I wouldn't want a stock FC for a DD, or any sports car for a DD, too many temptations, too many potential tickets or worse. But for a weekend car, or fun car, why not go big or go home?
First of all for anyone still considering a halfie or full BP, I have witnessed BDC's HBP on an FC here in Charlotte several years ago. It didn't matter what type of car meet we went to, when he showed up literally everyone's attention would be directed to the 'brap, brap, brap'... I have a vid, put you're not aloud to post **** on this forum.
Not only did the sound entice you, but when I lined up with him on the highway in my lightly modded tii and got pulled harder than any car I've ever raced (and he was still only running 9psi), I was sold (in fact BDC you will be gettin an email from me in the coming days). He would drive that FC daily without problems, the idle was loud, but not unbearable at all, (not as loud as my exhaust system with stock ports now if it idled over 1000rpms) and the entire car would rumble as it idled much like a cammed v8 would. And as others have stated previously, it pulled forever.
Personally, I wouldn't want one for a DD. I wouldn't want a stock FC for a DD, or any sports car for a DD, too many temptations, too many potential tickets or worse. But for a weekend car, or fun car, why not go big or go home?