I have straight 3" exhaust now with no muffler or res. I was wandering if anyone has ever thought about building a 4" exhaust system using tubing and elbows from a truck supply? Also how would I make the conection from the turbo for the down pipe? I thought mabe a 3" to 4" adapter .

 

Probly be better to run a 4" kit from a vendor. If you wanted to make your own, cut off the 3" end of your old exhuast and have it welded to the new 4" pipe and run with it. I think you would be money ahead to go with a prefabed 4"kit.

 

This is not about this topic but it is close.<br>Gas anyone built a valve that you put on you truck so it can be straight piped when you want it to and then muffled when you are in the city? I have a dad that hates the noise but I love it so I was going to fab up a valve but the only thing I can think of is maybe put a T right behind the resignator and have a valve at the end that I can open with a choke cable. I figure the back pressure from the Muffler and resignator would push the gasses out of the freer flowing tube?<br>DM01

 

Use a 3&quot; to 4&quot; expander at the bottom of the down pipe just ahead of the resonator that you will cut off and throw away. Replace the entire piece with 4&quot; straight pipe and use 2-45's with swages and one short radius 90 with a swage to make the dog leg over the axle. Cut the hangers off the old pipe and reweld them to the new one using the old tailpipe as a template. Weld all the joints except the one 45-90 joint ahead of the axle to make it easier to install and don't weld all the joints until you test fit it under the truck. I put a 4&quot; chrome turnout on the end to finish. Less than $175 front to rear and the sound is great. E-mail for help if you need it.

 

You could put a cutout in the exhaust system to keep a full system and then uncap it when you want to get loud ;D They're pretty popular on muscle/pony cars. Here's a small picture of one that can be welded into the pipe:<br><br><br><br>You can get an electric cutout to go on the open end that has a little flapper valve or gate valve (depending on type) that opens and closes with the flip of a button. They're pretty cool, but they're kinda pricey. Cutouts can be put in for ~$50, and you can uncap it in just a minute or so. The only problem would be all the smoke coming out under the truck.<br><br>John

 

I went to a 4&quot; with a Walker muffler and had it all done at a local muffler shop. Thet went from the downpipe to a muffler to a &quot;just in front of the rear wheel&quot; exit.<br><br>It was $275, labor and muffler included.<br>I looked at the companies selling the kits, and didn't see many for less than $400, although they usually include some sort of 10&quot; chrome tip <br><br>They couldn't bend 4&quot;, so I had to pay for pre-bent tubing, which was expensive.<br><br>I'd look at what the vendors sell, as well as checking out a good muffler shop and seeing what it'll cost you to do it at home.<br><br>Tackett

 

there's a few guys over on the tdr that have made there own 4&quot; system from truck exhaust parts works well and it's cheap from what they have said (really cheap). Just call around and check your local area for prices to see if it's for you, cost of parts in your area might not make it cheap for you.

 

I made the whole exhaust on my truck from pieces that I got at a truck parts store. In the end it cost right around $400 but that was for 5 inch pipe. I believe that the 4 inch is a little bit cheaper. If I had it to do over again I would order the tail pipe section from one of the vendors on this site and then get a piece of straight pipe and 3 to 4&quot; adapter from a truck parts store. Would save a lot of time and be much easier. The price would be about the same. You can order just the tailpipe section that goes over the axle for about $200.

 

Where can you order the tailpipe section from? I've been thinking bout getting it over my axle with a nice 5&quot; chrome tip tucked very close to my fender. That way I can see the smoke better. ;D

 

Helicopter Dan, I'm one of the guys from the TDR and made my own. It's a nice system and I do have a 4&quot; rinker truck muffler off of a 8.3 cummins application. It's deeeep sound is what's cool about it. The turnout is a 16&quot; stack top that I drilled for set screws and turned rearward a little. I like the money I saved compared to whats out there. I may go to a 5&quot; system after this summer and some additional mods I'm working on now. ;D

 

Well I installed the 4&quot; exhaust today and it sounds much better than the 3&quot; straight pipe. What I did was a 12&quot; piece welded to an adapter at the turbo from the 12&quot; piece of 4&quot; pipe I clamped a 24&quot; piece of 4&quot; flex to a 4&quot; staight pipe back to the axle then a 45 to a short radius 90 into another 45 and finished it off with a 90 turned out behind the rear tire. All welded together. Cost about 185.00 but very much worth it. ;D

 

I don't know what other mod's you have but you need something to cover the ground with black smoke now that it has a proper path to exit the engine from.