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-   -   what type of exhaust for Bridgeport 12a on the street? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/what-type-exhaust-bridgeport-12a-street-132000/)

corkbone 11-11-02 11:15 AM

what type of exhaust for Bridgeport 12a on the street?
 
I just wanted to see if anyone knows what kind of exhaust setup I should run on my 12a BP. I am driving this on the street by the way and I want to keep it down as much as possible. Right now i have a setup from racing beat, the muffler has the two slanted exhaust tips. The diameter of the piping looks pretty small though. Any tips?

RacerX7fb 11-11-02 11:35 AM

Hey corkbone is see you on the SDRX-7 Club emails. The RacingBeat Street Port exhaust system is the only thing I believe that you can buy that will keep the noise from a bridgeported engine down while still making power.
Tripoint Engineerings old FP autocross car had peripheral ports and was amazingly quiet due to an extensive lineup of mufflers running under the car, you may want to give them a call.
For a bridgeport to really work it needs the Road Race header running dual pipes all the way back then collecting to some kind of muffler that wont get roasted...which on the other hand That would be NOISY!
A custom setup is probably the way to go.
I'll be listening for the noise around town :D

FD Racer 11-11-02 12:43 PM

I just went from a RB single system (with the slanted tips) to the RB Street Port system. It's considerably quieter now with a deeper tone. It was a bit pricey, but the quality was worth it. If it were me, I'd get the RB Street port system.

rotarygod 11-11-02 02:49 PM

For a bridgeport I would definitely recommend some sort of long primary system collected at the back. I have the Racing Beat Streetport system and I personally have many problems with it's design. The header is fine, the middle section with the presilencers is o.k. but the muffler is not. The main pipes are 2" all the way through the presilencers. The muffler that Racing Beat uses only has 1 3/4" pipes which collect into a 2 1/2" pipe and then through the muffler. The rear flange where the pipe size decreases is terrible. Huge lip that restricts airflow. Optimally you would want to cut this factory collector off and replace it with new pipes that are 2" so there is no power lost from the reduction in area. Also the Racing Beat system did not fit very well under my car. It hits the heat shields and none of the mounting points they provide work properly. Mine had a nice podercoat finish that was beautiful. The exhaust now only has about 2K miles on it and the coating has burned off in many spots and the system has already started to rust. I live in Houston so there is no salt on the roads in the winter. I don't even drive the car in the rain much since the defroster doesn't work very well. I only bought the system from a friend for $300 who never used it and I feel like I paid too much for what I got.

The muffler is about to come off in favor of a warlock muffler from Summit Racing. This muffler has two outlets. One has a removable cap which makes it a straight through. With the cap in place it becomes a restrictive, quiet turbo style muffler. I am going to install a Q-tec electric exhaust butterfly valve which will let me open the straight through with a switch from the cabin. It will still look like dual tips but only one will work at a time. This would be a great setup for a bridgeport since they make the most power with little or no muffling and you can still have a quiet car with the flip of a switch. My friend has the same cutout on his Z-28 and it is so much fun to have a quiet car and then when someone pulls up next to you it gets loud. They always have the funniest looks on their faces:)

spoolin 11-12-02 12:25 AM

hey man, i'll buy it since you feel like you've paid too much for it. i'll even give you what you paid for it. i currently have a 4 port 13B sp in my GSL and am going back to a 12A sp. going to build a bridge out of the 13B and need another exhaust system.

corkbone 11-12-02 11:52 PM

exhaust
 
I guess I will just weld two pipes all the way back and run two mufflers side by side. I saw a guy do that before. Who can recommend a good quiet exhaust though? Anyone? Thanks guys. If I run the setup I have right now, Will it kill a lot of my power? I rather have a little slower car thats quiet, instead of something you can hear 3 blocks away.

Rotortuner 11-13-02 01:25 AM

I think your defenitely going to want to go with like a 2 and 1/2 inch collector if you collect or mabe even a 3 inch. I have a pp12a and i have tried to get buy with smaller but it just hasnt worked. the engine just doesnt have any pwr, due to the restrictive exhaust. I think a good tuned leangth is better than just running dual all the way back. If i were you, i would run 2 inch tubes all the way back and collect into a single 3 inch pipe behind the axle. put that into a 3 inch muffler and call it good. this way you wont have any restrictions and it might get rid of a little noise since its collected. Plus with collected it might scvange a little. This is similar to what i am doing. But i am going to build a new larger diameter header also, and i might go to a 3.5 inch collector.

CJG

DriveFast7 11-13-02 03:02 PM

If you got the RB dual pipe streetport system, ditch the RB muffler and it's pipe and have a new dual 2" pipe run after the presilencers, over axel and collect into a 2.5" straight thru Magnaflow muffler. I had this setup and I never got busted. Made good noise over 4k but if I saw cop I just idled it.


CJ is on the right track buy my god that will be loud. With ported motors it's all about compromise between power, noise, and tickets. Go with a min. 2.5" collector after the axel. And you might be able to get away with: after the muffler, put a 90 degree bend on the pipe to the drivers side and run a glasspack under the rear bumper. Bends to quiet it down and the glasspack will too.

I got a 12a SP in the racecar with dual 2" pipe over the axel that collects into a 3" inlet supertrapp with seven 5" discs for when I drive the car onto the trailer in front of the house. If I rev it over 2000rpm the dead start waking :0

-bp-

corkbone 11-14-02 12:40 AM

thanks for all the replys guys!!
 
But is there anyone here who has a quiet exhaust setup for a bridgeport. I laugh at guys who drive around with a nasty noisy car on the street. I dont like cops so I really want to keep it down.

NanaimoRx-7 11-14-02 01:11 AM

When I was at Rick Shaw Rotary in Australia, we were discussing what I could do to my car. And when we came to the subject of bridgeports, he said by the time you get the noise down to a streetable level you've lost what the bridgeport has to offer, and that I may as well go with a T2 swap, because it's quiter and offered more streetable power. Then again while I was in AUS I rode in a 12PP that was street driven so basically it's whatever you think you can get away with.

coldy13 11-14-02 01:19 PM

I plan on custom building a system like the RB Streetport exhaust. Use the Road Race Header, 2'' pipes with a straight through presilencer on each, collect right before the axel into a 3'' pipe, to a straignt through muffler. It would probably still be loud, since all mufflers are straignt through. I was thinking of having the pipes collect a little earlier to allow a 3'' straight through presilencer before the axel. It would help quiet it down a little more. It should flow very well too.

Rotortuner 11-14-02 04:13 PM

coldy13- your definetely on the right track. Its gotta be very unrestrictive.
I am not sure what kinds of exhaust ports you guys are running, but for me my sleeves are out and the usual racing beat headers just arent cutting it for me, they are too small ID for me. The exhaust comes out and hits the flange and that doesn help. So i am going to build a custom header out of SS that will have a larger ID. Is any one else having this sort of problem? Or is any one interested in SS headers that are larger ID?

CJG

Rotortuner 11-15-02 12:11 PM

So which set up are you going to use then?

CJG

heb09 02-21-04 11:34 PM

2 1/4 headers, with a resignator each, into 2 1/2 turbo mufler, then pipe then another 2 1/2 turbo mufler.

Fairly quiete until u openit up and flows beautifuly.


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