bcty

what are your guys oppinions on bridgeporting a street car? will it be driveable? and is it only reccomended for a turbo or can us N/A guys do it to. thanks.

No7Yet

I wouldn't recommend it, unless you enjoy...

- blowing engines every 30k
- blowing 5k on each engine
- not making ANY torque
- not making ANY useable power below about 4000 RPM
- being heard coming a mile and a half away (LOUD!!!)
- idling at 1.5-2k RPM
- getting 10-12 MPG
- cruising around at 5k like a motorcycle (well, that sounds pretty cool, but...)
- overheating if you don't continually drive the car

So, no, I wouldn't recommend it And no, with a bridgeport there's WAAAAY too much overlap for forced induction - you'd be blowing your intake charge straight out the exhaust ports

Brandon

bcty

what woyuld you reccomend for a street port.. i am looking for a lot of power and i dont mind not to much low end touque. how big can you go with a street port so u will have tons of power uptop.

SPZ510

I know of plenty of people who have run bridgeports on the street and with the exeption of the idle, none of your list of problems have occured for them. This is what I'm building right now, it's just about done and I have not spent anywhere near 5k. None of the bridgeports that I've spoken of have blown up either, with much more than 30k on them. Maybe the engines you were talking about were built incorrectly. I'm not sure but I wouldn't discourage anyone from running a bridgeport on the street. As for noise, dual exaust, two glasspacks and one muffler on each side will provide good noise control and not kill the power. It won't make crazy power but this is the trade off of not going turbo. If money wasn't an issue I'de go turbo. But that's big dollars, and those blow unless you have good detonation control.

bcty

well what would you reccomend then i am wanting to warp my tach around 10,000.... thats why im looking into a bridgeport. how much horse do u think i would be running with a good bridge port... will i have to upgrade rotors? obv fuel,air, ..... basicially what horsepower am i looking at and what will i need...

13B2QuIcKNy

First of all this is my first post.. and would like to say what up to all the fellow rx7 lovers out there.... about the bridge port... ive known many 12a and 13b's with it and it doesnt give any problems...u lose some low end torque but the high end is incredible.. my friend just sold a white 86 wit 13b housings and 12a side housings. bridge port, exhaust porting.. no cats and 2 1/2 exhaust piping, racing beat intake manifold , holley 650 4 barrel with a turbo II hood, and a bronze clutch and he use to run 14.5 constant.. and had no problems... it did swallow more gas.. but it got more than 10-12 miles a gain.. he got almost 210 miles a tank driving in traffic with the idle bouncing from 1000 to 1200 constant... and he never had problems.. the car was solid....

bcty

im looking for a redline of around 11000 or 10000 what was your friends and what kinda ##'s were you putting out?

No7Yet

Uh, either these people don't have bridgeports, or there've been some serious advances in the last year or so...

First, you'll save some money, yes, if you do all the work yourself. I'm assuming, since the original poster didn't say, that he won't be. Mazdatrix, Tri-Point, RP, and CCP all quote 5k+ for a well-built (all new parts, lightened rotors, e-shaft mods, hardened gears, etc, etc, etc THE WORKS) bridgeport.

I'd like to know who's gotten more than 30k out a bridgeport... no, seriously, throw some names out

As for your exhaust recommendation... uh, are you deef? Glasspacks will burn out in a matter of MINUTES on a b-ported rotary, and with that setup, it'll sound like a pissed-off-Mack-truck-sized-weedwhacker-on-CRACK from about a MILE away. My friend, bridgeports are almost as loud as a rotary can possibly get (with a PP motor only getting louder).

As what's this "It won't make crazy power but this is the trade off of not going turbo"??? Granted, not 600+ hp "crazy power", but 350 RWHP N/A at 12,000 RPM is pretty crazy for a street car.

All that leads me to believe that your friends exagurated (sic) the extent of their ports. Some big streetports require high idles, so that's not a single reliable metric Trust me, a bridgeport is NOT streetable, unless you're VERY hardcore. VERY VERY hardcore...

Brandon

RX-7Impreza

I posted about this recently an dif you do a search for 10,000rpms you will find it or just search with my my name. you have to do a lot of major $hit to get those kind of rpms. 10.5k is the highest i think you can go without a non-streetable race clutch and flywheel. then you gotta get lightened rotors ($$$$$$$) and all sorts of stuff. just do a search

Justin

Samps

At those rpms, I would recommend a scatter shield too. A clutch breaking up at 11000 rpms makes a mess of everything in its way. So I have read!

SPZ510

The problem with your redline figures is the flywheel rpm's. You'll need a scattershield and a tilton 5in. clutch/flywheel setup to spin 11k. You can do it but its not nec. Get a lightened steel flywheel for the street and that will be good enough. No stalling the motor at stopsigns. Power at the flywheel with a brigdeport will vary with the type of intake and exhaust you want to run. Webber downdraft carb and an open exhaust will get you 280 fwhp approx. This is not streetable though. The exhaust noise would be far too loud. Use the exhaust I mentioned before and now you;re looking more at 250hp. At the fly. Those carbs are pretty touchy so you might want to go with a Holley setup which will further sacrifice power to approx 240hp. It all depense on what you're comfortable with running. Is this a toy? Use the Webber setup and a louder exhaust. Is this a daily driver? Use the holley setup and muffle the crap out of it. As for the people that I speak of, one has a early 70's RX3 with the holley setup and the same exhaust I'm running. I'm not sure of his power output but his 1/4mi. times are 13.1 at 112. Pretty good if you ask me. I've ridden in this car and it sound good and has a very smooth idle, about the same as SoulAssasins car. A little smoother. Oh yea, he gets 22mpg!!!! He works for Motorsports Dynamics if you want him to build you one. He has reasonable prices. The other guys that I know of that have bridgeports on the street are a little closer to what that guy was speaking of but these engines were built as toys and not to be taken seriouly as comfortable or daily drivers. These were cop ditchin, donot doin, streetdraggin, neighbor pisser offers. And yes some of them didn't even last a month. But you dont have to build this type of motor. Let me know if u need any more advise or help. Theres plenty of it on this forum. Good luck.

Angel Guard Racing Team

Most of you guys are wrong!!!! You will not blow an engine every 30k unless you get Fred Flintstone to do the bridges. There are lots RX-7's here in Puerto Rico that are bridge Ported for daily street use. I used to have a 1979 RX-7 it was bridged ported, Racing Beat header and Intake manifold, holley 650 cfm a pair of jaycobs ignition coils and many extras. I had it with me for 4 years, no trouble at all!!!!! Plus it had A/C. Just got to make sure that the person who makes the porting does not do a shitty job that will eat your side seals.

SPZ510

OOpps, before I get slammed let me clear up the redline thing. The steel flywheel will let you spin up to 10.5k, maybe but with a street setup for intake/exhaust you'll taper off your power at 9.5k. That's high enough. Keep it under that for the street and you'll be much happier. If you really want to spin it to 10.5k you can but I would'nt do it very often if at all. Esp. for longivity sake.

SPZ510

Thanks Angel.

Angel Guard Racing Team

If they want to spin spin that hard they better have a good rear end

SPZ510

Ok, Thanks for your input Brandon, that's great.
As for names I'm not at liberty to put out my friend full name out on the internet fo anyone to see but if you'de like to talk to one of them go to Motorsportsdynamics.com contact Todd. And as far ***(no typo) the sound of the exhaust, it will or it does, have you ever actually heard this setup or are you just using your imagination together with your years of exhaust fab experience, Hey what would a Buick GNX with a hooker muffler out of a 3in. pipe sound like? Could you give me a example of that. 12k on the street is crazy sure but 350hp is not and no I'm not hardcore.

Kurgan

A bridge port would definitely be streetable, and unique in a 2nd gen. I say go for it... something that you may want to look into is what is known as a partial bridge port... thats when you street port the primaries and bridge the secondaries... kind of a best of both worlds... you get a bit more low end, still have the AWESOME idle sound, makes good power (you could prolly hit 240 or so rwhp), but top end doesn't suffer too much... true, anything over 10k would be pushing it, but thats about where a partial bridge (or half bridge) tapers off anyhow...

and about the statement about a bridge port having too much overlap for forced induction... just talk to Soul Assassin... he is running a huge turbo (T51R I believe, might be wrong on that though...) and a bridge port. Makes good power (I think he is getting up around 520 rwhp).

Do it. Bridge port it... or partial bridge. I am going to be putting a partial bridge port in an RX3 with a 60-1 this summer (thats the plan)... should SCREAM!!!! 10 second street car.

No7Yet

Heh. In the end, it's all up to him, but I still don't think a bridge would be worth the gutless low-end I guess I just like some torque...

Haha! yeah, but with a turbo that big, he won't be making full boost (all 14 lbs?) until, what, 3700, 4000 RPM? Heh, by that time the overlap times will be too small to matter I still think that with something like a T04B or E running 16-18 psi you'd be blowing your boost out the exhaust in the midrange...

Brandon

(Not a guru, I just play one on T.V. )

13B2QuIcKNy

my friend was revvin 10 grand constant with bridge port and no ecu... no ecu means no rev limiter.. so there u go.. and to add to angel guard racing team.. in puerto rico they are many bridge ported 1st gens or rx3's runnin as daily driver.. some even peripheral port..... no lie..

bcty

thanks for all the info guys... keep it coming. i was going to get s ahop around here to build it for me, he builts racing engines for rx's... i was intrested in the 1/2 bridge port.. anybody have this or have heard of anyone running this setup and what kind of numbers were they producing..

HWO

If you actually knew what you were talking about you could make some informative posts. now lets put the record straight.

BP engines will not BLOW every 30K.

You wont spend any more on a rebuild of a BP than you would on any other high HP properly prep'd motor.

BP's make MORE TORQUE than a street ported motor can achieve at any rpm ablove 4500.

You can make usable power below 4000rpm, but how many street ported motors do you know running REAL sized turbo's that make truely usable power below 4000rpm? most street ported motors are only spooling the turbo at around 3500........

It all depends on the exhuast system you run, a turbo muffles the sound particurly well.

a BP will idle sweetly at 1200rpm, my extended port motor idles sweetly at 1200rpm - NO DIFFERENCE

Add a turbo and you'll make well more than you would with a street port

as i said YOU HAVE NO CLUE!!!!!!!!!!!!!!

If you want a car that makes a lotta power, is still somewhat streetable, goes like a cut cat and is uneekly different get a BPT

HWO

aharrrmmmmmm - Soul Assasin made 500 and something rwhp with a T04e at 20psi.............

now what was it you were saying????//

rotary's are ment to be revved, you see to make good HP outta any small capacity motor you have to be able to get the volumetric efficency over 100%, you get this how? by having large overlap and pulling LOTS of RPM to get the 'natural' supercharging effect going

Dak

I thought I would mention it since no one else has.The stock n/a computer has a fuel cut at 8500rpm(or the 89-92 does,the 86-88 may be lower) so you have to something to it or you'll never spin past 8500.I don't know if any of the aftermarket chips remove this or not.If not you'll have to go with either a stand alone ECU or a carbeurator.Personally I would go stand alone if I couldn't get the stock one reprogramed.Also to continuosly run rpms above 8k the motor needs to be balanced and the rotors and rotor gears race clearanced which is what will drive the cost up.I personally think a bridgeport would be cool and may build one myself one day.

Dak

You must not have ever seen Soul Assasin's car,because as others have mentioned it has a bridgeport and it kicks ***.

SPZ510

Use a 1st gen dist. setup. MSD box and you'll have your redline set.

I'd like to hear more from Brandon, he seams to have a handle on this whole triangle thingy.