Bisimoto Pulse Chamber installation on my '85 911

kaidohaus · 05-07-2016, 08:44 AM

I have been contemplating an exhaust for my 3.2 since I took delivery of it some time ago. My car is an '85 Carrera, stock except for slight drop and corner balance, and ADVAN AD08R tires mounted on 16x7/8 Fuchs. My intent for this car is to keep it simple and fairly stock, something my wife could drive if she wanted to.

The one thing I wanted was to be able to hear and feel the engine more. It sounded like a sewing machine.

My wish list for an exhaust:

-smog legal
-not overly loud, but deep tone
-no drone
-stainless construction
-reversible, if needed
-performance improvement in both HP and throttle response

given that my engine is completely stock, I figured that just about anything on the market would serve its purpose.

Recently I discovered the Bisimoto Pulse Chamber and the first thing that struck me was that it looked nothing like I've ever seen. Immediately intrigued by the PC, I had in mind to research it further. I have met Bisi once a few years ago at an event and he was one of the nicest people I've ever talked to. At a recent event at Magnus' place, I met him again and asked about the PC exhaust. He was more than happy to answer my questions, and at that point I felt that going with his exhaust was the right direction. Bisi's responses were unique in that every tech question I asked was responded to with a scientific rationale. Very impressive!

I scheduled an appointment with Bisi, and yesterday I visited him at Bisimoto HQ in Ontario, CA.

Upon arrival, Bisi gave me a tour of his facility and I was blown away. All of his well known cars were there, and they are a sight to see in person. I am sure most of you are aware of his creations so I won't post them, I'll keep this focused on the install.

First, Bisi and his assistant hooked up my car on the dyno for a pass with stock exhaust.

with stock exhaust, 172HP wheel HP at 6200 RPM.

Time to get down. Bisi and his assistant removed my exhaust and weighed it- 21 lbs. Obviously there's going to be some weight savings here as well.

Compare to the Bisimoto Pulse Chamber:

I'll get to part 2 shortly.

kaidohaus · 05-07-2016, 09:17 AM

Lots of room with the stock exhaust removed. Looks like I can finally remove my AC bracket as well.

Bisi made a few adjustments for a perfect fit. He was very thorough in taking measurements and checking the details.

Time for another pass on the dyno with the Pulse Chamber. video below:

results:

That's a nice improvement in torque and HP! Proven dyno results.

The drive home was awesome, though most of it was stuck in traffic for 2 hours. When the roads opened up, it was glorious. First impressions: sounded great, improved throttle response and my butt dyno can definitely feel that power increase. It sounds sinister in the low RPM range and when you climb up it sings. No annoying drone noise, and it looks awesome! I couldn't be happier at the moment. Can't wait to some open road driving to get a real feel for it.

My neighbor did notice that the 911 was a bit louder than before.

I didn't get to take final install photos, but I'll crawl under the car to remove the AC bracket and take a few pics to post here.

J-Mac · J-Mac's Garage

What was the weight saving over stock? Sounds good too. Wonder if he does one for SSIs.

G50911 · 05-07-2016, 10:18 AM

how can i get one of these?

RFP · RFP's Garage

Quote:

Originally Posted by J-Mac

<<>> Wonder if he does one for SSIs.

I'd like to know also.

75 911s · 75 911s's Garage

Sounds good! Interested too.

Techno Duck · Techno Duck's Garage

Does anything support it from the tail pipe end? That's a lot of weight to be holding up otherwise.

Ive met Bisi a few times at various meets in the area, he is a super nice guy and actually remembers who you are!

pmax · pmax's Garage

How does it sound inside ?

kaidohaus · 05-07-2016, 02:00 PM

Quote:

Originally Posted by J-Mac

What was the weight saving over stock? Sounds good too. Wonder if he does one for SSIs.

Not sure of exact weight. I guesstimate around 5lb for Bisi's pipe.

kaidohaus · 05-07-2016, 02:04 PM

Quote:

Originally Posted by pmax

How does it sound inside ?

Sounds great. Music to my ears. Not too loud, perfect for me.

Seems like there's some interest- I suggest checking out Bisimoto Engineering's site www.bisimoto.com as the pipe is listed along with various finishes, prices etc. He mentioned that he's shipped quite a few pipes to Australia recently!

I'll also try to find out exact weight for those interested. It's fairly light.

kaidohaus · 05-07-2016, 02:07 PM

Quote:

Originally Posted by Techno Duck

Does anything support it from the tail pipe end? That's a lot of weight to be holding up otherwise.

Ive met Bisi a few times at various meets in the area, he is a super nice guy and actually remembers who you are!

Bolts directly to flange, it's lightweight, and I don't think it's an issue. As mentioned in my above post I'll get actual weight for those interested.

Bisi is definitely one of the coolest guys around! He fully stands behind his product too. Seeing his projects and listening to what he has to say is very inspiring indeed.

gshiwota · 05-07-2016, 03:33 PM

That looks awesome! Nice work!

impactbumper · 05-07-2016, 04:57 PM

sounds amazing. I want one now.

kjchristopher · kjchristopher's Garage

Quote:

Originally Posted by kaidohaus

Bolts directly to flange, it's lightweight, and I don't think it's an issue. As mentioned in my above post I'll get actual weight for those interested.

The factory muffler bracket also supports the weight of the cat hanging from the heat exchangers. Was anything added to provide similar support?

kaidohaus · 08:47 PM

For those who asked: the Bisimoto PC pipe is 5 lbs.

Also, a link to more info on his site:
http://bisimoto.com/2014/product/bisimoto-spec-porsche-911-sc-pulse-chamber/

kaidohaus · 05-07-2016, 09:09 PM

Quote:

Originally Posted by kjchristopher

The factory muffler bracket also supports the weight of the cat hanging from the heat exchangers. Was anything added to provide similar support?

I'll have a look underneath and confirm, and will also ask Bisi on Monday about this.

kaidohaus · 05-07-2016, 09:15 PM

Quote:

Originally Posted by impactbumper

sounds amazing. I want one now.

Would put that cherry on top on your silver car!

impactbumper · 05-07-2016, 09:16 PM

Quote:

Originally Posted by kaidohaus

Would put that cherry on top on your silver car!

On his website. That aem infinity pnp ecu is sweet too!

impactbumper · 05-07-2016, 09:22 PM

looks like 15lbs in savings. That is a lot

Bisimoto · 05-08-2016, 05:13 AM

Thanks for the kind words, Kaidohaus, and all. My team and I are very proud of this device, and all the joy, deep tone and power it provides. Cheers.

Quote:

Originally Posted by J-Mac

Wonder if he does one for SSIs.

J, not yet, but if demand dictates, I would have no objection in designing one.

Quote:

Originally Posted by kjchristopher

The factory muffler bracket also supports the weight of the cat hanging from the heat exchangers. Was anything added to provide similar support?

KJ, in the design phase, the moment of inertia surrounding the 20+ pound factory muffler system was studies tremendously. The two saddle straps are purely designed to hold the the muffler mass, with the weight distance from centerline as a concern. The Bisimoto pulse chamber significantly reduced this mass, and the location of the weight is now centered closer to where you want it...a location that does not require any additional support.
With a 5 year field test before launch, we have seen no negative effects, as well. I hope that helps.

Take care, all, and thanks again.