i want to replace my stock exhuast with a new 4 inch. i have a 2002 lb7 crew cab short bed. have been looking, but don't understand meaning of turbo back,downpipe back, catback, tip included and tip not included. what should i be looking for?

if you have a cataletic converter and want to keep it to be 100% legal(although your truck will run fine catless) you need a cat back system. if you dont have a cat or want to ditch the cat get one from the downpipe back. there isnt anything that replaces the downpipe, its miss makreting if it says it includeds the downpipe. Tips are those shinny things on the end of the exhaust. sometimes they are just shinny, sometimes they are bigger than the rest of the pipe so it looks like you have bigger exhaust.

There are many different exhausts that very greatly in price and quality. All of them sound different and that is very subjective. What do you want yours to sound like exactly? Also there are dual exhausts and just singles, some exit differnt from others. there are also "stacks" like what the truckers have that come up through the bed. Mostly exhaust comes down to personal preference on what you want it to sound like and look like. Or there is the trick of removing the muffelr with a peice of striaght pipe in its place. It should cost under 100$ to have a shop do it and if you dont like the sound then go buy a aftermarket exhaust. You wont really see any power gain from exhaust and dont need one unless you are maybe running a power programer.

If you do not have a cat, you're probably best served with a Catback system.

There are 5 parts to your exhaust:

Turbo downpipe - This goes from the top of your engine to about the crankshaft, and ends in a clamp. There is no aftermarket part for this yet. It is the most restrictive component.

Intermediate pipe - This goes from the downpipe to about the bed. It contains the catalytic convertor if so equipped. It terminates at a 3.5" GM specific 4-bolt flange, and is 3.5" dia.

Catback - This goes from the intermediate pipe to the back of the truck, and has the muffler welded in the center. 3.5" dia.

Muffler - 3.5" in and out, is welded in place on the stock catback.

Tip - A shiny piece of Bling-Bling on the last foot of the tailpipe. Appearance only. Stock trucks do not have one.

Your options:

Go from the intermediate pipe back - If you want to get rid of your cat, do this. It will reduce EGT's, and add a little performance and a new sound. If you do not have a cat, and you are looking for more HP, don't bother. Most aftermarket still have the GM-style flange which is 3.5" dia in the middle. So you go, small, big, small, big down the exhaust, which IMO is pointless. Often has the option of a Bling Bling tip.

Replace intermediate only - For cheap bastages, doing this gets rid of the cat to reduce EGT's. No cat? Don't bother.

Catback - This will reduce EGT's whether or not you have a cat, and gives you a new "sound" and a little power. It starts at the 3.5" GM flange, then opens to 4" or 5" (overkill = 5"). Often has option of Bling Bling tip.

Straight Pipe - Cut the muffler off, and replace with straight 3.5" pipe. Loudest, low backpressure, most obnoxious.

Cutout - Prior to the cat and muffler, put in a Y-junction that can be opened and closed. Open, it allows all gases to escape before the muffler, closed forces gases thru muffler. Run it open for competition, closed to reduce noise.

i like that driving away sound that ITP has on there site. my truck doesnot have a cat converter. i have, just installed a box. i think i probably need a larger exhaust now.

i like that driving away sound that ITP has on there site. my truck doesnot have a cat converter. i have, just installed a box. i think i probably need a larger exhaust now.
What is ITP's site? I have been looking for something to give me an idea of what aftermarket exhaust will sound like.

Andy

http://www.itpdiesel.com/

dbloyd & Andy02,

We have sound clips and pics of the systems on our site as well as installation PDF's.
www.dieselperformanceparts.com

Call us if you have any questions or need and help.

Mark @ DPPI

like the sound. thats what i want, but your listings say for four bolt flange or converter back and my truck doesn't have either one, also when i try to look at your installation pdf, it locks my computor up.

You should have a flange about were the bed starts and the cab ends. installs of quality exhausts systems is easy and can be accomplished with regular hand tools and a jack(to make getting the old off easier) some triming may be required to the intermediate pipe on some systems depending on your truck and the system.

Persoannly i would try to hear some systems in person. Maybe make one of the GTG's or see if there is a person fairly local. Cab sound can be much different and its all subjective.

thanks, those are good suggestions. i will look again for that flange. you know,i didn't have near this trouble choosing and buying a box for my truck. iam about to give up on trying to find an exhuast for it. there are so many diff. ones, and from there descriptions, it doesn't sound like any of them will fit my truck.

you should have the same 2 peice system as i had. ordering a full exhaust system if thats what you want will get you covered. There are a ton of choices out there

just what is the vendors description of a full exhuast sys.? they give many descriptions, thats confusing. like 4 inch front pipe back, down pipe back, turbo back, and 4 bolt back and cat. converter back. i wish to choose a full sys. and don't want to leave out any peices.

just what is the vendors description of a full exhuast sys.? they give many descriptions, thats confusing. like 4 inch front pipe back, down pipe back, turbo back, and 4 bolt back and cat. converter back. i wish to choose a full sys. and don't want to leave out any peices.
How about a full pictorial of the install along with a pdf print showing the pipes? That's how mine is listed...

thanks, thats what i needed.

downpipe back, turbo back, full exhaust will get you all the parts. If you go with a flange ot converter back you wont get a full exhaust. A call to a vendor here should get you what ever you want(just tell em what you want and they should help pick out the part #'s for you)

thanks a bunch.

Best bang for the buck.... get the MBRP 4" flowthrough muffler with 3.5" to 4" adapters (2x) and replace the OEM muffler. Lower EGTs and a nice rumble (a little too much for me in the 1600-1900 rpm range). Nice price and good results.