Rocket Man's 2008 Bagged CC Silverado Build AKA "THE MACHINE"

[Rocket Man]

I’m gonna have the shop see about doing something from the cats back. I know a change in the muffler will help. IDK, kind of out of options. I know I’m not gonna get the sound I want but it will change, believe me. Might just put an Aero Turbine muffler on it or none at all. Shorties will make a bit of a difference, not as much as long tubes I realize that. As far as cats, I know the super small ones advertised as high-flow which are the ones I’m looking at, which are used on Kooks or ARH y-pipes, might help. They will definitely take up less room than the huge stock ones so I won’t have the thing hitting the floorboard when I hit the throttle. I’ll do what I can and see what it sounds like. I’m just trying to not get bummed out.

 

[Rocket Man]

I’m thinking of the bullet cats like this. https://www.ebay.com/itm/262498636805

 

[iamdub]

magnaflow cat's are smaller than stock at least the ones the shop put on my 12 are

That they are, in both length and girth. Maybe the shorter length earns their "high flow" designation? I don't know. I got an offer for around $260 to recycle my OEM cats, so that's what I'm gonna do with them.

 

[iamdub]

I’m thinking of the bullet cats like this. https://www.ebay.com/itm/262498636805

Do you have to have cats for emissions or___? I was under the impression you wanted it more on the rowdy side. Cats make great mufflers. lol

 

[Rocket Man]

Do you have to have cats for emissions or___? I was under the impression you wanted it more on the rowdy side. Cats make great mufflers. lol

No, I don’t need them. The downstream sensors are tuned out and it’s registered in a county with no emissions testing. But no muffler shop will work on it without cats or at least they will only work on it back from where the cats are supposed to be. I pretty much need a new system from the shorties back. Nothing is stock, it’s been built to fit the truck. I can’t even remove the system without cutting the muffler off- it’s one long contraption all welded together. You can see it in the video I posted earlier. I’m not even sure how they built it. I pulled it loose at the manifolds and dropped the front down but the muffler won’t let it come forward and out from between the rear crossmember and bed. They must have welded the muffler on with it like this, then lifted the front up and mounted it to the manifolds. There’s no way to weld the top around the muffler without dropping the front so you can spin it to get to the top. I might be able to weld pipe where the cats are if I leave the rest alone and just put a muffler on with clamps if I don’t take it to a shop. This isn’t like a truck where I can buy a system that fits and install it myself, it has to be custom bent.

 

[iamdub]

No, I don’t need them. The downstream sensors are tuned out and it’s registered in a county with no emissions testing. But no muffler shop will work on it without cats or at least they will only work on it back from where the cats are supposed to be. I pretty much need a new system from the shorties back. Nothing is stock, it’s been built to fit the truck. I can’t even remove the system without cutting the muffler off- it’s one long contraption all welded together. You can see it in the video I posted earlier. I’m not even sure how they built it. I pulled it loose at the manifolds and dropped the front down but the muffler won’t let it come forward and out from between the rear crossmember and bed. They must have welded the muffler on with it like this, then lifted the front up and mounted it to the manifolds. There’s no way to weld the top around the muffler without dropping the front so you can spin it to get to the top. I might be able to weld pipe where the cats are if I leave the rest alone and just put a muffler on with clamps if I don’t take it to a shop. This isn’t like a truck where I can buy a system that fits and install it myself, it has to be custom bent.

I'm trackin. Yeah, you're kinda in a bind unless you do it yourself. I get what you're saying about it all being welded in place. I welded my muffler in place because it was much faster to do it that way than to make it "removable". It wasn't convenient by any means. I couldn't fit my head up there to weld the top with my hood on. So I aimed, squinted tight, pulled the trigger, moved by feel, checked my work and repeated until the top was fully welded.

My eyelids were burnt!

If you could come up with a way to section it, band clamps are a convenient and solid option.

 

[PG01]

I'm trackin. Yeah, you're kinda in a bind unless you do it yourself. ................
If you could come up with a way to section it, band clamps are a convenient and solid option.

This one time, at band camp..... ohhh you said ‘clamp’..... my bad carry on...

 

[Tonyrodz]

This one time, at band camp..... ohhh you said ‘clamp’..... my bad carry on...

Stuck a flute in.........

 

[Rocket Man]

The EBay idiots I bought the console lid from never shipped it, just provided a tracking # so I got a refund and ordered one off Amazon. But I’m thinking that latch will probably break too and I want a strong one so I drilled a hole through the thing with a 1/16” drill bit, cut the bit to length, and used it as a metal rod to strengthen it and then bought another tube of Fusor 142 Plastic Repair Adhesive ( I wanted some on hand anyway) to use as a repair. I think my design is strong. It turned out a bit messy because it’s about 95 in my garage and the Fusor has a 5 minute working time in normal conditions, today I think I had about 2-3.

 

[Rocket Man]

Put the lid back in; can’t even see the repair and it works great. Probably way stronger than the original.

 

[Sam Harris]

Put the lid back in; can’t even see the repair and it works great. Probably way stronger than the original.

View attachment 250928

Great work as usual Mark!

 

[Tonyrodz]

Great work as usual Mark!

As usual.

 

[Rocket Man]

Thanks guys. I got the shorties installed today and I’m running with no muffler ATM. I ordered a SLP Loud Mouth bullet muffler, it’s about all I have room for. I wanted to get an Aero Turbine but at 6” tall there was no way, a 4” tall muffler is all I can fit. Then I’ll see what i can do for a turn down. I have almost no room left over as far as length. Right now it’s terrible in the cab so I’ll see what the SLP does, plus I need to get the exit farther back. It’s under the rear seats now. Anyway they look good in the engine bay. I did have to modify the firewall on the passenger side and the heat shield on the driver side, and I took my 5lb mini sledge to the floorboard right where it angled up, where the cat was hitting and vibrating so that’s fixed. That drove me crazy, every time I hit the gas hard it vibrated and rattled bad. Got a new sticker for my toolbox. Oh, and Justin is working on my tune to help with more chop by pulling timing at idle and lowering the idle. It’s still idling at 800 for some reason.

 

[Sam Harris]

Thanks guys. I got the shorties installed today and I’m running with no muffler ATM. I ordered a SLP Loud Mouth bullet muffler, it’s about all I have room for. I wanted to get an Aero Turbine but at 6” tall there was no way, a 4” tall muffler is all I can fit. Then I’ll see what i can do for a turn down. I have almost no room left over as far as length. Right now it’s terrible in the cab so I’ll see what the SLP does, plus I need to get the exit farther back. It’s under the rear seats now. Anyway they look good in the engine bay. I did have to modify the firewall on the passenger side and the heat shield on the driver side, and I took my 5lb mini sledge to the floorboard right where it angled up, where the cat was hitting and vibrating so that’s fixed. That drove me crazy, every time I hit the gas hard it vibrated and rattled bad. Got a new sticker for my toolbox. Oh, and Justin is working on my tune to help with more chop by pulling timing at idle and lowering the idle. It’s still idling at 800 for some reason.

View attachment 250995 View attachment 250996

Sounds great Mark!

 

[iamdub]

Thanks guys. I got the shorties installed today and I’m running with no muffler ATM. I ordered a SLP Loud Mouth bullet muffler, it’s about all I have room for. I wanted to get an Aero Turbine but at 6” tall there was no way, a 4” tall muffler is all I can fit. Then I’ll see what i can do for a turn down. I have almost no room left over as far as length. Right now it’s terrible in the cab so I’ll see what the SLP does, plus I need to get the exit farther back. It’s under the rear seats now. Anyway they look good in the engine bay. I did have to modify the firewall on the passenger side and the heat shield on the driver side, and I took my 5lb mini sledge to the floorboard right where it angled up, where the cat was hitting and vibrating so that’s fixed. That drove me crazy, every time I hit the gas hard it vibrated and rattled bad. Got a new sticker for my toolbox. Oh, and Justin is working on my tune to help with more chop by pulling timing at idle and lowering the idle. It’s still idling at 800 for some reason.

View attachment 250995 View attachment 250996

I didn't know you went back with a stock cam.

 

[Rocket Man]

I didn't know you went back with a stock cam.

Yeah I don’t like this exhaust. I am extremely limited though, there’s literally zero room. I might have that shop give a shot at building something but I’ll have to leave cats in if I do. They will just be really small cats. Right now it sounds like he’ll inside the cab, probably because it exits straight out the back with no dump, and that point is under the rear seat. I need another 24” of length to get it near the back of the cab where it was. The muffler will get it close, then I’ll see about a dump. I can’t find any real short 3” ones and I need it to be about 6” long I think.
Edit: I’m hoping the tune will help but it’s taking forever.

 

[Rocket Man]

I cancelled the SLP bullet and ordered a Borla 40359 that is the exact size as the original Magnaflow, and a Flowmaster short 3” turndown. This will put the exit where it used to be. I can’t go further back, there’s a crossmember in the way and no room over or under it. I’ll try this combo with the tune and see how it sounds before deciding about the cats. Borla 40359 Muffler https://www.amazon.com/dp/B000Q7MBTK/ref=cm_sw_r_cp_tai_stv-EbJQ9YDWD

 

[iamdub]

Yeah, at least getting it past the back of the cab will make a big difference. You have a wall there separating it from the passenger compartment unlike in an SUV, so it's almost like having it exit out the back of the SUV. Well, other than it resonating under the bed.

 

[Rocket Man]

Yeah, at least getting it past the back of the cab will make a big difference. You have a wall there separating it from the passenger compartment unlike in an SUV, so it's almost like having it exit out the back of the SUV. Well, other than it resonating under the bed.

Yeah it’s bad right now aired out. I went grocery shopping today. I got to the store and did what I always do- laid it out. The comps were still running filling the tank and I always let it fill to 200 psi so when I come out I hit the remote start and it brings itself to ride height and then refills the tank again while I load groceries and get rid of the cart. But it sounded so bad inside laid out that I hit the ride height button and then it took even longer to pump up because I just used a bunch of air. I’ll let it fill the tank first and THEN air it out from now on. I really need to get it to exit through that space between the cab and bed.

 

[iamdub]

Yeah it’s bad right now aired out. I went grocery shopping today. I got to the store and did what I always do- laid it out. The comps were still running filling the tank and I always let it fill to 200 psi so when I come out I hit the remote start and it brings itself to ride height and then refills the tank again while I load groceries and get rid of the cart. But it sounded so bad inside laid out that I hit the ride height button and then it took even longer to pump up because I just used a bunch of air. I’ll let it fill the tank first and THEN air it out from now on. I really need to get it to exit through that space between the cab and bed.

Pretty sure I already know the answer, but how do you feel about the exhaust exiting through the panel? I mean having professional body work done. Not those cheap trim pieces that you cut a hole, screw 'em down and route the pipe through that. I'm thinking more of an arch(es) formed into the very bottom in the area in front of the right rear wheel. Have the tip(s) come out there. It'd technically be under the panel rather than through it.


NOT this:

Something like this, but way cleaner. Have the notch(es) match the tip(s):