Exhaust being done Monday

[96cherry]

going to have my exhaust done monday, im putting shorty pacesetter ceramic coated headers 2 and a half inches all the way back no cats dual super 40 series flows with stainless 3 and a half inch tips. (think it will sound good?)

 

[General Stalin]

The only thing that would make that engine sound possibly any nastier than that would be if you had no mufflers at all. That will be a loud and throaty setup you have there, for sure. Just wait until you actually break the mufflers in, then you'll be turning heads everywhere.

 

[96cherry]

exhaust

how long is it going to take to break the mufflers in?. do you really think its going to sound bad. give me some advice please

 

[GMCYukalade]

I don't think he meant that it would sound bad.. - i think he meant it would sound very good..

 

[General Stalin]

I didn't mean "nasty" as in bad... I meant it like it will sound really aggressive and loud. It will be deep, chuggy, and sound like a muscle car. It shouldn't take more than like a week or two to really break it in. Do a lot of highway driving and open the throttle. That happens with all mufflers (especially noticeable in performance mufflers). You have to pass a lot of exhaust through them to sort of "work them in."

I have a Flowmaster super 40 single-in/dual-out muffler with 2-1/4" side exit pipes in my truck with 12" chrome tips 2-1/4" -> 3.5" and I'm very happy with the sound. When I first got the exhaust system done for my truck, the minute I started it up and tached it up a little in the shop parking lot, it sounded pretty decent, but not quite what I expected. I wanted it to be a little louder than that. I noticed over the next 4-5 days (I do a lot of highway driving) it started sounding deeper and more growly. After about 2 weeks it was pretty much worked in and sounded really nice. I got the tips about a month after and my brother welded them on for me, and then it really sounded sweet.

Your exhaust system will sound a lot louder, aggressive, and throatier than mine. You are getting a true dual system with no cats, which is pretty much as unhindered as you can get. Except for the mufflers (which will sound really nice), the sound that comes out of those pipes will pretty much be all engine, just toned down to a volume that is street legal.

 

[GMCYukalade]

Just expect a loss in tourqe - it may not be very noticeable, but it will be there

 

[General Stalin]

^ This is true.

Back pressure is a fickle thing and some engines need it to certain degrees to perform just right.

 

[96cherry]

i appreciate all the advice hopefully it will sound as expected thanks.

 

[General Stalin]

Honestly, though, the loss of back pressure shouldn't hurt these 350's much at all. I mean, they need SOME back pressure, but the mufflers should give you enough to make the truck run fine. You usually only run into real noticeable back pressure problems with smaller engines.

 

[96cherry]

i was kinda hopin to gain a little low end this thing is a dog on take off. any advice for some pep at low rpm

 

[jneal]

i was kinda hopin to gain a little low end this thing is a dog on take off. any advice for some pep at low rpm

what gearing are you running, usually regearing is the best answer for that Q.

 

[96cherry]

im not really even positive. how would i find something like that. its the stock gearing

 

[GMCYukalade]

I've posted this in another post, but here ya go - what you do is, get inside that glove box, take all the stuff out of it, and look down inside there is a sticker with a bunch of mumbo jumbo on it called RPO codes - this is all the options on your specific vehicle...

The rear-end RPO codes are

GQ1 -- AXLE REAR, STD RATIO
GT4 -- AXLE REAR, 3.73 RATIO
GT5 -- AXLE REAR, 4.10 RATIO
GU4 -- AXLE REAR, 3.08 RATIO
GU5 -- AXLE REAR, 3.23 RATIO
GU6 -- AXLE REAR, 3.42 RATIO
G80 -- AXLE REAR, LIMITED SLIP (POSITRACTION)

HC4 -- AXLE REAR, 4.56 RATIO

- Now, if you have say.. a GU6 and G80 - that means you have 3.42 gears w/ a posi locker

 

[jneal]

look on the diff and see if there is a tag attached to one of the bolts. it will tell you what gears are inside.

if the sticker mentioned above or the tag is not there, the easiest way is to drop the drive shaft and spin the differential flange. count how many times it turns to make the tire turn once. On jack stands of corse. it will give one of the ratios listed above.

A dealer may be able to get a spec sheet from your VIN as well. This may list what you have. Mine was listed as 3.73.

 

[96cherry]

ok found it ive got the 3.42 not even the posi locker, no wonder i cant get both tires to spin

 

[GMCYukalade]

- Also, You won't gain any low-end (tourqe) with a really wide open exhuast.. - thats what i meant when i said to expect a loss in tourqe - which you may have not noticed it at all it may still be the same..

- I'm pushin a 3.42 - with the G80 (however 2 of my rear-ends where no g80) and i've got pretty decent take off - these things are HUGE - not meant to spin tires on ashpalt..