Taming the Bridgeport exhaust
 

Here's a review of RacingBeat PR power pulse muffler.
Old exhaust was blown out Magnaflow. At idle over 100decibels haha. With RB road race header and 3" pipe to the new PR muffler noise went down to 86 Db 's. Low and mid range power picked up significantly and no significant top end power was decreased. I took it one step further and installed the RB 3" universal resonator and noise went down to 82 db's. Power still feels great and sound at cruise is very mild but when you get on it it sounds good! I highly recommend this muffler combo! Here are some pics.
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Note: I had to mount the muffler at an angle because on the 616 the spare tire wheel well takes up a lot of room. The RX models have a lot more room and can be mounted straight. I think it looks cool hehe

Sound clip


Sent from my iPhone

sounds GREAT!!!

Did you make that collector? I'm going for something similar
I have the road race dual presilencer and pipes collecting at a 3" dynomax (too loud)
I want to move to the universal 2.5inch power pulse to quiet it down
But maybe collect it earlier so I can add a second resonator

Wow, that looks and sounds great! The RB powerpulse mufflers really do work well.

When you fed the pipe into the powerpulse, did you cut out the original inlet and weld the 3" on there? Or contract the 3" down a bit to match the inlet pipe size? What version of the muffler was it originally? 79-80? 81-82? 83-85?

This is the new "PR" (Puerto Rico) power pulse muffler. They opened the inner muffler diameter to just under 3". So it flows much better but still cuts out a lot of noise. I did cut the 6" extension and welded the 3" pipe right to the muffler inlet body. This muffler really works and I'm very pleased with the power! I may extend the two primary pipes back further before I collect into the 3" to see how it performs. And yes I did make the collector and welding.

Interesting. I hadn't heard of the PR version before. I wonder how it would work on a turbo setup.

I'm not trying to be a hater or anything, but haven't these mufflers been dyno proven to restrict a significant chunk of horsepower on builds that rely on heavy breathing? (AKA: big port rotary).

I know your butt dyno is happy but... Well the facts.

that's real quiet on idle.. well done.

if you're still making power with that noise output then you are doing very well.

is it idling around 1,300rpm?

up over 3,000rpm is when they really start making noise.

how about some vid of you tossing it a few revs?

[QUOTE=tasty danish;11453312]I'm not trying to be a hater or anything, but haven't these mufflers been dyno proven to restrict a significant chunk of horsepower on builds that rely on heavy breathing? (AKA: big port rotary).

I know your butt dyno is happy but... Well the facts.[/QUOTE

Like I said before, this is a new muffler they just came out with. It flows much better than the old power pulse mufflers. Will it create back pressure and cause some power loss at high rpms? I'm sure it does but for a street car that has to meet sound levels by law and still have good performance, this is a very good muffler. There's no muffler in the world that will quiet an exhaust to law standards and not cause some restriction and power loss. To have the best of both worlds then I would recommend installing an electric exhaust valve so that you have open exhaust for racing and on flick of the switch back to full exhaust. But for me this system has plenty of power the way it is.

So just so i understand...this is a Racing muffler that has been modified? or is this a racing beat look-a-like made in PR? just curious?

Agreed. Tell us more. Where do you purchase this muffler? How much?

RX7 1975-1985: Exhaust - Cat-Back Systems: Power Pulse PR-Extreme RX-7 Muffler - Universal - 79-85 RX-7 -

sweet, this is exactly what i've been wanting for mine!

Pretty sweet!!! Sure wish they would make it with a single tip dumpy

Yes that is the muffler, thanks for posting. I think most guys can get by without a resonator and just this muffler. The resonator really helped with the raspy sound though.

WOW! I may have to get one of these mufflers.

thank you for posting! like i say this is the muffler i wanted, i just didn't know they actually made it.

b) nobody asked why you have the shock absorber on the steering?

Shock absorber on steering??
I remember Rene had told me why he put it there but I don't remember exactly what it was for,ultimate jay do you know what it helps doing?

Just a wild guess, but steering dampeners are pretty popular on jeeps and ford workvans and such...which have pretty similar steering setups to old school rx's and first gen Rx7's...ever hit a bad bump wwhile making a turn in an old pick up or similar??? Steering wheel usually gets ripped outta your hands from the force...if you dampen that force you can hang on to the steering wheel and maintain control of the vehicle. As applied to Rene's old car I would imagine plenty of front wheels in the air launches with a 20b in there...in which case the steering damper might help the driver maintain control of the car as it comes down...just a theory...thinking out loud. I really like that exhaust too...its just what a lot a people have been after for a while. I bet RB will sell a lot of them.

I didn't lose any power and possibly picked some up from going to a 2.5" single exhaust with a pair of straight through perforated-core mufflers to the complete RB long primary system. I don't know which muffler that is, but it is a perforated core muffler and not a restrictive baffle type.

That was on an intake restricted half bridge.

My non intake restricted full bridge also is happy with the RB system. Exhaust backpressure is less than half of what the old cobbled-together system was, and did I mention that the car is QUIET?

Yes this muffler is a straight through perforated design which flow a lot better than baffle type mufflers.

Regarding the steering shock- Rene told me he put it on the help with the the steering from jerking when hitting grooves. Basically to mask worn steering components lol. He said it worked really well. I don't have a before and after test so I don't know. The steering needs to be rebuilt and I will most likely take it off. The shock is probably blown out lol

There was a shock like that on the white truck's steering. I took it off and steering improved. lol

Wow that muffler. I'm just... I'm probably going to have dreams about it.

Yeah I'd love to hear some more of that - give 'er a few revs maybe a drive-by!

I'm a few minutes away from pressing "buy" on this myself.