I'm looking for a good 3.5" down pipe as well, so far all I've found is Diamond Eye's aluminized steel set up. Has anyone used these and are there any other options?

 

Why not just get a 4" downpipe and exhaust? They fit fine on the Super Duty trucks.

 

The Super Duty have a little more room for a 4" down pipe. On an OBS truck, you'll have to do some major firewall modifications with a hammer and a block of wood to get a 4" pipe in there.

 

Mostly ,i was thinking, if I go the t4 route I don't want the quick transition from 3" to 4". As I tired that I realized my mental image was wrong. I guess what I would need is a quality 3" DP-back.
it maybe I can find a 3-4 transition pipe in the 3' range, hmm

 

Yes but I am pretty sure we are all talking about the 99+ trucks here.

 

I am 99% sure that the T4 kit from CSD has a 3.5" downpipe. I bought clamps and adapters to go from the 3.5" downpipe to my MBRP 4" exhaust.

In the 99+ Powerstroke trucks, there is plenty of room for a 3.5" or 4" downpipe and if you are making your own T4 kit, choose whichever you like to mate up to the exhaust of your choice.

 

Here you go. Pictures taken today while swapping transmissions. Not the best but a different view than usually posted

 

Nice pics Brandon.

I guess I should have been more clear on my thought process. I don't feel the need to go bigger than the supplied downpipe for the remainder of the exhaust. If the CSD kit is supplied with a 3.5" DP that should mate perfectly with the stock exhaust. However, my stock exhaust has about reached the end of it's service life. I am loath to let a local muffler shop replace it so I need to find a decent replacement. Before learning about the T4 setup I was planning on the MBRP 4", I might still do this.

BTW, thanks to all of you guys who are leading the way on this.

 

I would just go with the 4" kit. They're available, reasonably priced and work great.

 

I need to fess up to my cheap nature regarding the 3.5" down pipe for my modified stock turbo. My exhaust is still in good shape and with the 4" Aeroturbine muffler flows a good bit better. I'll eventually swap to a 4" system but am looking for a stopgap solution to the stock downpipe's less than adequate diameter/flow, thus my quest for a 3.5" replacement. Any ideas or experience with existing products?

 

Where are you from.

Edit. I have a 4 inch down pipe I've been trying to give away but I am too lazy to ship it. It is in the classified section and the free parts thread.

 

Brandon,
I'm in northern Georgia, a good hike from your neck of the woods. I appreciate the offer though.

 

Started putting my t4 CSD kit on today. I have the t4 mount in and the down pipe sbf up-pipes in. What does everyone think about the oil line angle? Do you have return and feed going straight up and down or at angle? Or do I just get the turbo in and what angle works then I'm good? The Brad let me know to not go over 20 Degree of angle with center section.

 

 

I attached the return line then rotated the center section so it was as far down as possible and backed it off just a tiny bit.