Guys with B&B's...

How much backpressure do you think their muffler produces? (a lot, a little, none, etc.)

I heard a while back, that the Lightning guys were having problems keeping these systems "together" during runs down the strip. Backpressure was popping them apart at the joints.

After making my first couple of runs down the strip last Wednesday, I noticed I have an exhaust leak at one of the joints before the muffler. I checked it out, and the pipe seemed to have slipped back about 1/8", allowing exhaust gasses to puff out of the two slits in the female side of the connection.

Now, I'm not sure if this was a thermal expansion thing, backpressure thing, or pure coincidence.... but I was surprised at the "velocity" of the exhaust leaving the relatively small leak. It leads me to believe there is a fair amount of backpressure.

What's everyone thoughts?

 

Just the right amount. Before the stall My sotp meter felt no loss of low end.

My experiences;

5.3 with az long tubes, gutted cats and a BBdual back catback. The system is a single 3" into a muffler with dual 2.25 pipes exiting out through the roll pan.

last trip to the dyno I ran the truck one pull.
Than I unbloted the catback from the 3" joint and pushed it out of the way. I than ran the truck again.
Not a very scientific method because the computer didn't have time to adjust for the open exhaust but I only saw a gain of 5hp and 4 tq above 5000 rpms.

That leads me to beleive it is a good flowing muffler.

I hav'd to adjust the clamps that came with the kit occasionally becasues I think there a poor design. I put some stainless ubolt clamps on there now and they seem to be working fine.

I beleve it's a well balanced setup.

 

Wow, that's it?

After thinking about it a bit, I do agree that it's probably a good balance. I remember my top end picking up a bit after putting the exhaust on my bone-stock truck. It was a little more 'free revving' when winding out first.

I still can't help wondering what a true straight through muffler like a Magnaflow might do if swapped in place. I may throw one together this winter.