finally got the exhaust sorted out

[bmwdon]

So using BBK's SS headers/high flow cats, I originally tried putting on a 2.5 X pipe into the LS3 exhaust....wow did that suck nuts. So I cut off the LS3 mufflers, kept using the X pipe and 2.5" SS piping to the rear and used a reducer to reinstall the LT mufflers. That reduceds some of the craptastic rasp sound as the LS3 tips were like trumpetts exaggerating the rasp caused by the X pipe. But them KMPrenger told me about a site called magnaflowplus.com and I ordered magnaflows part# 11379, it's the X pipe, perforated and surrounded by ss wool and the muffler bod of course. Man, what a improvement in sound, swapped out the bare X pipe for this, put the LS3 cans back on it, and the wife loves the sound. simple burble at idle and down low, and a decent sounding WOT growl. no drone to complain about.

Gonna let this settle in for now, and look to do the heads when I squirrel enough cash away for tune and dyno time.

[Beauwulf]

Cool! Audio please!

[formare]

If you run this part #11379 (which is listed as a muffler) do you need the rear mufflers? Can you just run straight pipe to 4" tips in teh back?

[CAMAR0]

I love my LS3 mufflers too... Maybe one day bbk lt will join them ...hmm

[KMPrenger]

Originally Posted by bmwdon

...But them KMPrenger told me about a site called magnaflowplus.com and I ordered magnaflows part# 11379, it's the X pipe, perforated and surrounded by ss wool and the muffler bod of course. Man, what a improvement in sound...

Awsome! I'm really glad this settled things down and worked out!

Originally Posted by formare

If you run this part #11379 (which is listed as a muffler) do you need the rear mufflers? Can you just run straight pipe to 4" tips in teh back?

Well, I'm thinking it has been done, but I'm not sure how great it is. Some companies like SOLO are doing something similar, but I believe they also have resonators in place after their dual in / dual out muffler.

There is a link on the sticky exhaust thread, to a youtube video from member kellyjrt, where he also uses a magnaflow dual in / dual out muffler (resonated X I presume), and what appears to be resonators directly after the muffler. Check out the video here. I think it sounds pretty good.

[bmwdon]

you know, I never tried to run the exhaust without the rear ls3 mufflers on after I put the 11379 in place in the middle (replaced the original H pipe and the X pipe I tried to use initially). Maybe I should have! sorry. But being that the ls3 mufflers are supposed to be straight through and just perforated into the big chambers, I don't know how much louder it would be? maybe just a little bit? the 4" tips do seem to amplify the sound of anything coming down the pipe to them though, that's for sure.

[bmwdon]

so I ran through a puddle this morning about as deep as a damn kiddy pool, and the exhaust must have been hot cause after I got to work and opened the doors before I turned off the engine, it sounded like a huge air leak underneath the car....crap! the force of the water must have slipped the exhaust apart as it's held together with clamps right now. So I think, no sweat, get her home and slip things back together and retighten for now until I can get to the exhaust shop and have somebody weld it up for me. I guess the heat of the pipes and the dunking in water wasn't good for a slip fit set of pipes held together with U clamps I can't get the damn things tight enough to not leak like a siv, so I'll hopefully get it to a exhaust shop this weekend and have them weld it together, cause it sounds like hot ass right now and the wifes smile is no longer there