With 12 years and 160K miles gone by, the stock muffler was starting to get a little questionable looking. The thought of having it blow out 500 miles from home on a vacation was not a happy one.

So I read and read and read some more. Despite 10 points for being USA made, I never liked Flowmasters because they sound tinny and nasally to me. And tend to drone in the most annoying way. But some folks I have come to respect on these forums say they sound OK on the V10. And many sound clips of other mufflers sounded horrible to me...

I tow a lot. And I hate loud ricer cars. Deep and rumbly is good. Popping, raspy, farty, and loud droning sounds are all quite unacceptable. Yeah, I'm in my 40's now. I still love a race prepped Ducati Desmo, my Triumph Triple with Sebring race pipe, 500 cc British singles, and SBC's with Dynomax Super Turbos. But loud I4's, V6's, and V10's? Huh-uh. I know what is loud and pleasant, and what is just loud.

I took a deep breath and installed BB50. Granted, I installed in a way that would allow easy removal... And left the stock tailpipe and exit location. Those are key! I have stock manifolds, SBC Y-pipe, stock cat.

My (admittedly very sceptical) review:

Start up and idle: Not bad. Not bad at all! A touch louder. Maybe a bit deeper in tone. Only a bit of the FM metallic ringy sound at idle. Quite acceptable.

Acceleration: Again, not objectionable at all! I'm OK with it.

Big test: 15 minutes at 1/2 to 3/4 throttle and towing 12K pounds up long grade: Hey, only about twice as loud as stock! Can still hear stereo, can have conversation in cab. Again, not bad at all.

So there you go. The BB50 on a V-10 doesn't sound nearly as bad as I expected! It sounds better than ANY exhaust I've heard on a V10 short of the stock.... I'll leave it in place!

Oh, the power difference? Didn't notice any. Maybe a dyno would show a few lb-ft here and there, but honestly, not enough to notice. It sounds like it's making more power (more noise), but I have driven these mountains enough to know the actual power is not much different.

 

I wouldn't mind seeing some installed pics if you have them. Interested in seeing the fit as the 50BB is 2" wider than the 70BB2, I caoulnd't mount either of the 70s completely flat due clearence issue. I installed two 70BB2 thus far on V10s and they seem to work and sound good as I suspect the FM50BB should too.

The muffler will break in and the tone will change slightly. Overall I like these large capacity flowmasters for the V10 despite them being overpriced and very rust prone. If FM would make these mufflers out of stainless and keep the price the same I think more people would buy them.

 

Great Review! My thoughts exactly the FM series all seem to sound ok on 2v v10's.

 

I'll try to get photos up. In case I fail or forget, here is verbal:

I removed stock muffler at the slip joint about 12" in front of it, and cut the tailpipe off right at muffler.
I had to extend the tail pipe about 4" to have a straight section to plug into FM.
I used a straight section of 3" pipe to fill in between muffler and stock pipe from cat.
I used 53052 muffler, with center inlet and offset outlet, offset put to top.
I mounted in stock location using modified stock bracketry. The stock muffler had a 1" wide strap wrapped around and welded to it. I cut off the straps, re-shaped them to fit the FM, and bent the ends outward to make bolt flanges. A hand made inverted omega shaped strap and a couple bolts mounted it up. The result is the muffler is mounted like stock, with wider dimension up and down. The top of the case is about 1/2 to 1" closer to stock heat shield, which was retained.

The front corner of the BB50 does hang down a couple inches lower than stock. I could have tucked it up another inch or so by modifying stock pipes and mounts a bit, but I wanted some clearance for heat shielding purposes since we tow hard. With the 35" tires and F350 blocks, it has not proven to be a clearance issue. Anything tall enough to hit the muffler would definitely take off cab steps, interfere with axle and driveshaft, and hang up on spare tire and receiver. We did some 4x trails this past weekend to explore some mines, and never touched it. Did "modify" the reciever a couple times....

 

A sound clip would be great if you could. Great write up!

 

Great review and write up, very informative, reps sent.

 

Do these mufflers have weep holes when the inevitable water will collect?

 

Do the stock mufflers have them?

 

BB50: No weep hole
Stock: Yes, weep hole.

I will probably be drilling one in mine, although my application is low need. Usage is pretty much a LONG drive or no drive.

 

I have a BB50 on my 03 F450. It is very quiet (just a bit louder than stock) except a mean growl between 2-3K RPM's. In a quiet neighborhood late at night? Just keep the R's below 2,000.

 

Quieter than the FM70?

 

I called Flowmaster a few months ago while I was researching, and I recall the tech (or was he just a sales guy... hmmm...) saying the BB50 and BB70 are very close in internal baffle construction and sound levels, with the BB50 EVER so slightly quieter and less raspy (ie, deeper tone) due to the larger chamber volumes. The key thing I remembered was that if I could fit it, it would be closer to meeting my objectives.

 

Follow up:

I've put a few thousand miles on, including a few hard pulls.
Still no complaints!
It is quite possible it has aided torque just a bit.... It seems like I can hold a given gear a bit longer up the big grades.