rotatech7

street ported or half bridge?? on a s5 all motor fuel injected
im trying to find a thread about it but i cnt find it any opinions??

AlexG13B

iTrader: (7)

there is a huge thread under "Rotary Performace"

https://www.rx7club.com/rotary-car-performance-77/bridge-port-over-rated-629931/

Blake

That thread is about turbo bridge ports, which are a completely different animal.

With respect to NAs, bridge ports definitely have greater potential. However, I am not a fan of the so-called half-bridge. It's a bit like being half-pregnant. Either you are or you aren't. Even with the secondaries closed the engine still "sees" the port and communicates. If you want a bridge port, just go all the way and have the full benefit. Just be prepared for the compromises and realize that potential does not always equal performance...the whole system needs to work together to realize potential. Just a large streetport, exhaust, 6-port inserts and a S-AFC camt net you 190hp at the wheels with hardly any compromises. A bridgeport may or may not exceed that and the compromises are significant.

NoviceRotaryTech.

Theres alot of these threads it seems.

Anyway, I too was pondering the same Questions, but I have made up my mind on this kinda subject with my n/a aux-BP plan.
Seem a lot of ppl will tell you to "go all the way" or just go with a good street port.

But what are you looking for, an all motor drag machine, or a street worthy machine??

dean23

Bridge Port and Daily Driver do not belong in the same sentence. they call it a "Street" port for a reason....

stupidkid0304

I've personally seen and known bridgeport, both half and full, to be good daily drivers. I have also seen a car get 30 mpg (I DO NOT KNOW HOW). I am, and forever, pick a bridgeport over anything else.

diabolical1

iTrader: (3)

i agree with Blake on this. if this is going to be a ported 6-port engine, then streetport it.

rotaryengineering

Go with a Street Port you'll much happier in the long run. Most people like to here the BRAP BRAP BRAP crazy idle that Bridge Ports create. But if you ever have to drive the car for long periods of time you will get sick of it eventually. Not to mention if you really want to make power it will have to be loud. At least with a Street Port the exhaust can be somewhat quite, and still make good usable power.

Good Luck

Dom_C

i say go bridge. I have a half bridge turbo and it's very very streetable. I don't understand how people can think that they arn't streetable, it is very easy to drive. The only drawbacks i've found have been tuning in vaccum, it's a bitch, and it's ******* loud. Other than that I love it.

Blake

Speaking as someone who has driven a Peripheral Port 13B with Weber 51IDA, puck clutch, 4.88 rear end gears, heimed links, full cage, no interior, yadda yadda on an 8,000 mile round trip from Oregon to Florida and back -- pulling a tire/tool trailer -- I can honestly tell you that "streetable" is a matter of interpretation. However, my definition is more about practicality. A daily driver should not be a chore to drive. It needs to have comfort, convenience, economy, etc. A car you don't think twice about firing up at midnight for a quick run to the convenience store without waking up the neighbors, or drive a couple hundred miles to visit your friends or family without concern that it will break down or burn up all your gas money for the month. That's my idea of a daily driver. Your mileage may vary. One of the guys that works for us has a flat black FC that is SLAMMED to the ground, riding on bump stops, with a zip-tied on body kit and no interior. There are parking lots he cannot drive through because of speed bumps or curb-cuts. It rides like a buckboard even on nice, smooth roads and the exhaust is very drony. But it looks cool in his opinion, so it is his daily driver. Personally, I think it's stupid, but that's just me.

stupidkid0304

I've also driven a bridgeport for a daily driver and found it to have no problems.

stupidkid0304

^half-bridge

Dom_C

i agree, i don't take my car out for quik trips at night really because of how loud it is. I do find it to be very reliable though, only problems i've had sense getting it together are I keep popping off intercooler piping/hose's and i have a pretty bad oil leak at the pan right now that I've been putting off fixing. Other than that reliability isn't a problem. But yes starting often takes a bit longer than a stock engine, and High vac has to run a bit richer in order to stay smooth so gas milage goes down. The drivability is great, it's just not always conveniant as a DD. Never have a project as your DD

Meatkibble

I went with a streetport for reliability issues, and i felt it was easier to just buy a template and do it myself. Now my ports look badass and all i have to do is throw it together...

rotatech7

well the engine is done ,half bridge. lets see how it runs..

Roen

iTrader: (2)

hope you have a custom intake mani and a standalone to realize that potential......

DelSlow

iTrader: (2)

You'll love the half-bridge. 90% of the people who say that drivability sucks and a streetport is so much better have never even driven or ridden in a half-bridge and have no idea what they are talking about. I was worried about noise and drivability when I decided to go with it, but now I would never go back to a streetport.

Roen

iTrader: (2)

remember, he wants an HBP NA, not an HBP Turbo.....there's no such thing as increased spool response with the HBP NA.


Just curious, what's your mileage on your HBP's? I get 24 highway on my car.....I would think mileage is a very important thing for a DD.

diabolical1

iTrader: (3)

exactly. much different sound level (inherent muffling) and torque curve.

Blake

And 90% of people singing the praises of a half-bridge have never driven a full bridge port, and thus don't know that they are making all the compromises and getting only some of the benefit. And, they most likely don't know the full potential of a quality streetport.

Here is a dyno sheet of an S5 NA with a large streetport, full exhaust and SAFC: 189.9 RWHP. It won't pass emissions, but it idles smooth and sounds nice and quiet.



All NA half-bridge guys: post your dyno sheets to support your anecdotes. If I can find some, I will then post what a real bridgeport does (we mainly do J-ports, because bridgeports are too limited).

BTW, I personally prefer a peripheral port over a bridgeport...the compromises are similar but the performance difference is night and day. I used to put about 10,000 miles a year on my peripheral port car (8,000 miles to Florida and back, plus a couple thousand just around town), which other than the noise was a dream to drive.

Roen

iTrader: (2)

Agreed, most people who go BP don't realize that the BP is an inferior port compared to the PP in NA trim. The BP was created to get around the ban on PP's placed on certain classes. PP's make more power, and are also much louder.....if you like that kind of stuff.

SASSER

I drive a T2 half bridge and I hate driving around in it sometimes, it's annoying in traffic, at lights, at stops, and just to much head ache if you drive it daily or even weekend warrior it. The extra power at top end just doesn't make up for the lose at low end driving around wise. Go street port.

BDC

That's funny. You could've fooled me. Been daily driving me for nearly 3 years now.

B

rotarygod

iTrader: (1)

The one constant I see among bridgeport owners who drive them on the street is that they are all turbo. It doesn't take much to hit any boost at all and when that happens, your drivablility issues are gone. A turbo also works somewhat as a muffler although they can still get pretty damn loud.

An n/a bridgeport however can't be made quiet without losing an awful lot of performance. It is extremely dependant on intake and exhaust tuning as there is no boost to compensate for it. Boost does wonderful things. If he is still using the stock intake manifold with a bridgeport, he isn't even going to break 200 rwhp and that is attainable without a bridge. Remember this is an n/a S5 we are talking about. Everyone's experience with a turbo bridgeport doesn't really apply to nonturbo cars.

Since he's running fuel injection, it had better be a true standalone and not an R-tek or SAFC. He NEEDS to be running either a Weber or a Holley style intake manifold or equivalent and a true header system with a straight through muffler. It will be worthless without the total setup being matched to it.