I received my cat back mbrp sytem today and I remember reading somewhere to install the muffler backwards. I did a search for mbrp and could not find the post. What do you guys think? Install backwards for backpressure or install as directions indicate? Also received my predator today. I will be installing everything tomorrow night.
Thanks

I received my cat back mbrp sytem today and I remember reading somewhere to install the muffler backwards. I did a search for mbrp and could not find the post. What do you guys think? Install backwards for backpressure or install as directions indicate? Also received my predator today. I will be installing everything tomorrow night.
Thanks
if you have the reversible muffler then its basically for sound. there are louvers inside the muffler.. face them open towards the rear of the truck and it will be louder..face them towards teh engine and it will act as a baffle and be quieter.

I don't think it would give enough back pressure either way since its a straight through muffler and not chambered.

Thanks for your input BrianO. Anyone else? Oh by the way BrianO, good looking truck you have there.

LLY or LB7?

Sorry! Its a 2004.5 with the LLY.

I installed mine as per instruction and there is nothing loud about it. I have their cat delete downpipe also and i run predator/edge, it is awesome.
joe

ka41 sorry just realized youve got a cat back setup.........others have stated that a complete exhaust system will throw codes, but installing muff backwards seemed to correct.............
hotrent1.......are you running finger sticks and an egr plate?

So the best thing to do is install as per the instructions and not backwards.
Any tips for the catback install. Looks pretty simple.

I am using fingerstick and egr plate and just got predator and no dtc codes to date.

Hardest part of install was removing old exhaust. Get your truck up as high as you safely can. (jack stands) Spray rubber hangers with wd40 and workem off one by one. Did not cut mine or anything. I do plan on taking to muffler shop and having connections welded and remove clamps.

ka41, I installed the MBRP turbo back system and eliminated the kitty on my 05 lly. I installed the muffler backwards as instructed by the dealer that sold it to me. He stated that reversing the cones would provide enough backpressure to keep the lly happy. I/m not getting any codes yet but it's also not very loud. Actually has a nice sound. Maybe it would be louder installed with the cones facing backwards as instructed. I'm not an expert on this so can't tell you much else.

Thanks for your input BrianO. Anyone else? Oh by the way BrianO, good looking truck you have there.Thanks, just saw your note..

if you are keeping your cat then the only thing the direction of the muffler is going to do is change the sound. I have been through all of that once already with mine. The LLY's are very touchy with back pressure so you need either the stock muffler or the cat installed. If you remove both then you will need the block off plate and finger sticks or you will get the famous 0401 and 0404 EGR codes.

if you remove the kitty, then the only backpressure you will have is by reversing the muffler so it acts as a baffle. The LLY's are actually much quieter than the LB7's anyways so it won't make that much difference in sound.

I had a complete exhaust system on mine, sold it to a buddy with an LB7 and his is VERY loud.same pipes, same muffler, everything.

good luck!