Exhaust on B&B headers

[bbh03]

Hi,

I've read in the past that there is a different distance between collector pipes on the B&B headers. Is this true? If so, what exhaust options do I have that will fit? I do not want a B&B muffler (the one I have is crappy). The car is a 1978 SC 3.2SS / 964 cam. Pretty much a track car, so no cat and noise not a big problem. I'm willing to cut the rear valence for 2 out.

Thanks!

[jstgermaine]

M&K now makes a muffler that works with the B&B set-ups.

[Bill Verburg]

Originally posted by bbh03
Hi,

I've read in the past that there is a different distance between collector pipes on the B&B headers. Is this true? If so, what exhaust options do I have that will fit? I do not want a B&B muffler (the one I have is crappy). The car is a 1978 SC 3.2SS / 964 cam. Pretty much a track car, so no cat and noise not a big problem. I'm willing to cut the rear valence for 2 out.

Thanks!

You can use a Flowmaster and 2x U pipes, cut and welded

looks like this

[einreb]

I currently run a Dynomax (similar setup to Bills pic above), but I find that too loud. That replaced the Fabspeed setup (still sitting in my garage) because I found that way to loud. Fabspeed is a rebranded Flowmaster if I'm not mistaken.

Of all the posts on b&b headers and exhaust options, I've never gotten the impression that any are 'mild sounding' and some have some noise/resonance issues. People use reducers, cap one outlet, resonators, et cetera. Some folks seem to like the volume. I'm still looking for a little more understated setup.

I was just exchanging emails with Ben (MK Exhausts that Jerry linked to) about a setup for my b&b headers that would be quieter.

[Bill Verburg]

I currently run a Dynomax (similar setup to Bills pic above), but I still find that too loud. That replaced the Fabspeed setup (still sitting in my garage) because I found that way to loud. Flowmaster is a rebranded Fabspeed if I'm not mistaken.

Corrrect Fabspeed header muffler is a rebranded Flowmaster.

They are loud, but the 2 muffler setups that I find myself mesmerized by are the Fabiani/Flowmaster and dual Coast setup.


They just sound right.

[Jeff Alton]

Bill, are you talking about a two out set up with that are seperate from each other ala the original megaphone type design. As in each bank of cylinders has its own seperate system so to speak. I hope that makes sense, having a little trouble putting it to words........

Cheers

[Bill Verburg]

Originally posted by catca
Bill, are you talking about a two out set up with that are seperate from each other ala the original megaphone type design. As in each bank of cylinders has its own seperate system so to speak. I hope that makes sense, having a little trouble putting it to words........

Cheers

The Coasts are a dual out setup



The Fabiani/Flowmaster is a 2x In/2x out crossflow.

[JeremyD]

I have a magnaflow SS dual out. I also wanted one of the MK mufflers but the spacing is too much and the one Ben does have exits out the back under the license plate. The Magnaflow is part # 14386 using 2.5 inch inlets and outlets. I also used two Magnaflow 4" tips (part# 35136). It's loud - but not too bad for a cabriolet.

I have a sound file somewhere...

[efhughes3]

I've got the Fabiani setup on my headers, and it sounds great, maybe a touch loud sometimes. I get a lot of compliments about it.

jakermc on this board just dropped a vario 3.6 into his SC with the Coast dual mufflers, and it sounds like a monster. Very gutteral as he passes you on the track (ask me how I know!), it vibrated my car!

[Jeff Alton]

Hmm, I have a line on the coast stuff at quite reasonable prices so I am contemplating that avenue for my B&B set up. Mind you, I have so much work to do still that I have plenty of time to think about it!!

Is there any power/torque to be gained or lossed by not having the exhaust from both sides combine in a muffler or cross tube??

Cheers

[bbh03]

Wow, so there are certainly some options. Does anyone know if the two separate race style (Coast or the MK) clear the valance on an SC?

Bill, was the pipe fabrication for the flowmaster difficult? Any challenges?

Thanks!

[mb911]

the MK does clear the valance

[einreb]

Originally posted by mb911
the MK does clear the valance

Ben,

Just called and left you a message on your business line. Can you do a b&b to a single side outlet?

-Bernie

[bbh03]

Ben, how loud is that race exhaust. Too loud for infrequent street use?

[Bill Verburg]

Is there any power/torque to be gained or lossed by not having the exhaust from both sides combine in a muffler or cross tube??

even fire 911 6's don't benefit form a x-over in the same way that odd fire American V8s do.

[klaucke]

Originally posted by catca
Is there any power/torque to be gained or lossed by not having the exhaust from both sides combine in a muffler or cross tube??

Some would argue this is open to debate, as they feel a crossover is helpful. Steve Weiner has posted before that he thinks these engines benefit.

However, from the physics perspective there is nothing to be gained b/c Porsche flat 6's are even fire motors and can achieve optimal scavenging w/ a single bank of the motor, because the cylinders alternate firing evenly. Bill Verburg has numerous excellent posts on the subject:

http://forums.pelicanparts.com/911-engine-rebuilding-forum/255235-3-6-muffler-change-loss-hp-torque-post2295709.html?highlight=champ+ferrari#post2295709

http://forums.pelicanparts.com/porsche-911-technical-forum/258187-my-new-exhaust-system-pics-post2324938.html?highlight=even+fire#post2324938

EDIT: I hadn't refreshed the webpage when I replied and didn't notice that Bill V already posted!

[bbh03]

Does anyone use this MK race exhaust or have track experience with it? The price is right (250?)

[Jgordon]

Ben made me buy a set of the race mufflers at hershey. They're 10 inch cherry bombs. I'm guessing they're gonna be a blast, but probably too loud for street driving (either you'll get tired of them or the cop will, but either way someone's going to tell you to stop).

Ben could comment more on them. I'm going to try them out this weekend if I can - I'll report back.

[Jeff Alton]

Thanks guys, I may go this route shortly...

Cheers