just recieved my 4inch down pipe. and i want to install it so bad but my buddy thats gunna weld on the rest is on vacation.

my question is, is it bad to just run the down pipe? since there wouldnt be any back pressure? thanks

 

No problem with just the down pipe
The downpipe is one of the big restrictions

 

thats gonna be pretty loud

 

I didn't mention to get a reducer and couple downpipe to existing exhaust
the other big restriction is the muffler

 

There's no such thing as too little backpressure on a turbo diesel. The turbo itself provides much more backpressure than you might realize.

 

Sounds as though you are putting in a custom exhaust since you mention welding; most, if not all, exhaust systems you buy (such as an MBRP) have clamps so you do not need to weld.

Consider ceramic coating the downpipe; I did this and cost me only $90; looks great and ALLEGEDLY will provide greater exhaust extraction capabilities due to the thermal properties of the pipe being able to be contained in the pipe. I know others here will be able to articulate this better than me.

I researched this fairly extensively and there does not seem to be any real hard on the road type of data to support this but I figured for $90 what the heck. A plus is that the coating will ensure the pipe has a longer life

 

Why weld it? I just used the V-clamp and its fine...

 

ok thanks for that, i just didnt know if it would affect performance and what not. but im still using the v clamps at the turbo housing, im welding after the downpipe, since my buddy owns the exhaust shop its gunna just cost materials.

 

No such thing as too little backpressure on ANY 4-stroke engine.

I don't know if I'd classify "drive pressure" with "backpressure" anyway. The cam timing on our factory diesels does not provide/allow for any "backflow" into the cylinder anyway.

Not trying to correct you, Curtis.....just being my overly-analytical self.

Oh, and to the OP:

If a straight pipe off of the turbo at a length of 2-3 feet hurt performance, all professional truck pullers would run full-length exhaust.

 

haha light bulb over here thanks for that.

 

Dang, you had to break out the dictionary didn't you


Gotta bust your chops once in a while to keep you in line

 

haha it is trust me... When i installed my 4", i ran outta time and had to run straight downpipe for a week. If it was legal, i mighta left it hahaha

 

haha thats guna be awsome

 

I had to do the samething...I was trying to break the install down into halves and cut most of the system off and just had the DP left. You can definitely hear the turbo a lot more. I thought it sounded great and if I hadnt spent 400 on the system wouldve prolly left it like that as long as I couldve gotten away with it!

 

Where can you purchase just the 4" downpipe? everywhere I've seen only offers full systems.