Yeah it should be awesome based on what I've heard and read. But I gotta know if having a 3" midpipe and muffler fed into 2.5" tails and y pipe kill performance and airflow?

 

It didn't seem to hurt the performance on mine at all, but I have a 2010 (if that makes any difference).

 

The mechanic at work said I was pretty much dumb for going for a 3" into 2.5" tailpipe. I'm still skeptical about hi flow cats as well. I'd hate to pay all that money for them plus install to have them possibly throw codes at me or not last very long, etc.

 

It will improve performance, and sound. Larger diameter will not restrict air flow, it increases. Velocity is your worry, which barely any pressure will be lost. The more open pipe exhales better, and the sound punches the muffler harder with the allowed flowpath and a lovely note is always provided. You enhance the sound, sound projection, reduce minor popping when cold, gain mid & high rpm performance. More restricted piping is always best for those who tow heavy loads of your hitches limit, and for those who don't want to be heard from a block away.


Firstly, in his defense, you told him it was going to be Y piped 2.5" dual pipes ( basically a SI/DO configuration that is not an actual muffler, which does not hurt performance ), correct?

Secondly, I would like to know his 'opinion' on these guys running full 2.5" true dual exhausts in these trucks. Must be retarded huh? . It will not hurt anything, even if you ran single 3" to a single 2.5" tailpipe. Hell some manufacturers find that that can actually increase velocity and lower droning under highway cruising.

Hi-flow cats will not hurt anything, if done right. Meaning, the installer drop the downpipes from the manifolds, FULLY weld them in place of OEMs, not the half-ash get it darn close method smaller shops will try, then you will be tissed off by the hissing/ticking/clicking sound you hear from the leaks formed by the poorly welded catalytic replacement job. And as long as the O2s are not damaged, dropped, or dusted up prior to install, and most importantly mounted AFTER the new smaller cats to fully clear the catalyst that does the work of making a cat filter what it needs to, you will be gold.

And third, If that was his exact response to your question, I would have some choice words myself for him .

You will be fine, get it all done. If you do, I will too. Wait, I am doing that kind of stuff anyways, sweet!

 

Ha! Thanks for the honest opinion Darren! I'm sure some of us at the shop would agree he is not the best tool in the box. He is an ambulance diesel mechanic (durasuck and powerstroke) so I'm not sure what he has against bigger midpipes! My current set up has a 3" midpipe now so hopefully the shop will be able to fabricate my new set up pretty easy. I have Fartmasters SIDO now and as soon as I heard 08FX4's set up, I fell in love with that sound and I had to have it. I've had this set up for a few years so it's time for a change.

He does know about the Y pipe after the 3" magnapack and said that was silly. But thanks for clearing up with your explanation of the pipes, I knew it couldn't be that bad since the magnapack itself is a straight through muffler and sounds great plus the Y pipe gives all that moving exhaust 2 places to exit. I just hope my 3x18 tips will sound like 08FX4's 4x18's, mine are straight out the back slash cuts and i'd like to not spend more money changing those.

As for the hi flow cats, my shop around here is excellent and has been around forever, I recommend them to everyone. Here is the information I got from them over the phone: If I went with 94106 cats, they would charge $60 a piece to install plus $35 a piece to weld in 02 bungs an inch behind the cats like everyone recommends. If I went with 94136, which has the o2 bungs built in, I wouldn't have to pay them to weld the bungs in saving $70 bucks. I may hold off on the cats for now and see how it all sounds with stock cats when I get the parts in and set up a time for them to do it. If I can avoid messing with the cats, that would be best for me but if I decide to get them well that's not a problem. Yes yes I know everyone here loves their 94106's!

Hopefully I will change teams to Magnaflow once this is all said and done then post some videos, hopefully my camera will want to cooperate and record a decent video.

 

Good deal man! Yes, a Magnaflow SI/DO which outperforms its chambered rival, is nothing more than a Y pipe with a t-409 case and rockwool wrapped around it.

& remember, the only difference in 94106 & 94136 are one has O2 mounts, the other does not. The one without ( 106s ) are guaranteed no CEL with the O2 past the catalyst. The 136 is not so guaranteed to not trip a CEL by accident due to the installers own fault. The mounts in the cats are right past the catalyst, so they do clear, but if the O2 sensors have finger prints, dust, or are set on something that will scratch them they can get an improper signal. All the fresh hot metal from the brand new catalyst may want them to trigger the CEL too but not very likely. A tune solves all, when deactivating rear O2s. All they are doing is verifying the catalyst is filtering gases. The Magnaflow units do that just fine, just much more louder than stock!

 

Okay I'll keep that in mind about the 94106's. It shouldn't be a big deal to go back later and add the cats if I want them at some point. Just can't wait to see how the magnapack sounds in person.

 

This is actually good to hear, since you now know not to listen to him. lol

Mig, what kind of sound did you get in the interior of your truck with the Bullet?

Darren, you had mentioned it is a"choppy" sound. Care to elaborate? Reason I ask is because I actually like the "thump" from the engine while driving.

Thanks!

I would install the exhaust setup you want and check to see how it sounds before deciding you want high-flow cats. You may be perfectly happy without them.

 

Yeah sorry to take your thread to a different topic Ark!! I know nothing about Bullets :/

 

I had some definite drone. Was pretty loud at 2200 rpms if i can remember correctly. Been in a while since ive driven it. It was LOUD when I towed, but around town it wasnt anything I couldnt tolerate. If you dont want a noisy interior, the bullet is not your muffler.

 

Some noise doesn't really bug me. I like to be able to hear it inside. I like the sound of the Magnapack at cruise, just wish it was louder inside.

Is the Bullet just a loud bass type of sound inside or is there a growl/thump/whatever that you can hear at cruise?

@Dave. No worries!

 

It depends where you exit the exhaust. As long as you dont dump it, it will be a nice grown inside. If you dump it, you will just get bass type noise. I LOVED the sound of it when it was exited before the rear tire. It was such an amazing sound inside and out. Toned it down inside by putting it out the back behind the rear tire, but still had a nice growl inside. Man...talking about that truck's exhaust makes me miss it even more!!

 

I'm tempted to give it a go just to see what it's like.

If I do, I'll probably go for the 12" 3/3 Stainless Steel Bullet (full system is stainless).

My exits are 45'd behind the rear tires.

The "growl" inside is what I am looking for. Like I said, I like the Magnapack sound inside but it is quite subtle at cruise. I like a little more "anger". lol

 

DO IT! Its a $40 muffler so if you dont like it, worst that happens is you swap mufflers. My 12" 3/3 bullet was aluminized. I dont think they make that size in stainless.

 

They do now.

http://www.summitracing.com/parts/WLK-24248/

$66. Not too bad. I have a Magnapack on currently so I'd probably pick up some cheap Summit Stainless Pipe to make up the difference after the cut/downsize.