Exhaust Question

[willy1947]

The '04 Dodges do not have 4" exhaust all the way from the turbo back, right? There is a section that is smaller, right?



Does anyone make a kit to replace this section and would it help much to make it all 4"?



Thanks,

Dave

 

[XcumminsX]

4" dp that goes to 3. 5 ... . 3. 5 to the muffler... . 4" the rest of the way

 

[FAST4DR]

Originally posted by XcumminsX

4" dp that goes to 3. 5 ... . 3. 5 to the muffler... . 4" the rest of the way

So is there advantage in going with a tru 4" and if so, which brand is recommended?

 

[JNutter]

Did the 305/555 '04s have a different down pipe than the 305/555 '03s?



I just measured mine (2003 HO), it's 3. 5" from the turbo back to where it expands to 4" just after the muffler. There's no 4" down pipe on mine.

 

[Agades]

same here

mine is 3. 5 at the turbo to the muffler



a lot of people with earlier 03s have said theirs has a 4 inch down pipe then necks down



mine dont



whats the deal here



did dodge have a bunch of spare parts laying around for the last 03s made



the cast elbow on my turbo is smaller at the exit than the very back of the turbo

 

[Ken F]

I am in the process of putting some pictures in the readers rigs section. I had a Banks system installed today, and I brought the stock system home in my snowmobile trailer. It is assembled as one piece, except for the cast elbow. (It is now a loose piece. )



The inside of the stock cast elbow that goes between the turbo and the stock down pipe measures Ø3. 77" where it attaches to the turbo and Ø3. 20" where it attaches to the stock down pipe. Quite a restriction, eh?



The remainder of the stock exhaust is Ø3 1/2" from the elbow to the muffler. After the muffler, the tail pipe steps up to Ø4".



I am going to post a picture of the removed exhaust assembly and the cast elbow.



For what it's worth, I highly recommend the Banks system. As I understand it, their's is the only one that does away with the cast elbow. If you put on someone else 4" system, you are putting it on behind a Ø3. 20" restriction.



I bought mine from Diesel Power Products. They were very good to deal with.



I have to go put my kids to bed, then I will post the pictures of the amputated stock exhaust.



Ken.

 

[Joseph Donnelly]

With that tiny 9 sq. cm. turbine housing on the HY35, 3. 5" is fine and way big. If you want to make an improvement, replace that monstrous muffler with a straight through, perforated core muffler. Don't expect a huge gain, though, because you are feeding that muffler through a soda straw.

 

[Blakers]

I bought a 4" straight through muffler that I'll put on once the weather gets a little warmer out. It's got one male end and one female end. The mail end has an ID that is just right to go over the 3. 5" existing pipe. Hopefully an easy install. $75. 00.



Blake

 

[SOLER]

Originally posted by Agades

same here

what's the deal here



did dodge have a bunch of spare parts laying around for the last 03s made

That's exactly what the exhaust on my Y2K truck looked like. Just a bunch of different pipes clamped together!

 

[RDietze]

Originally posted by Joseph Donnelly

With that tiny 9 sq. cm. turbine housing on the HY35, 3. 5" is fine and way big. If you want to make an improvement, replace that monstrous muffler with a straight through, perforated core muffler. Don't expect a huge gain, though, because you are feeding that muffler through a soda straw.

that is exactly right. i also installed the banks and after inspecting the turbine from under the truck, i noticed the turbine is about 1. 5" in diameter (at the discharge into the exhaust plumbing) -- the "new" restriction for me now has become the hy35 turbo.

 

[EMD-Run8]

I too think the 9cm housing is smallish and would like to find something that may perform better eventually (a straight bolt-on) if that ever happens. The Banks system is the only one I know of that replaces the 3. 5-4" cast elbow. I too bought mine through Diesel Power Products along with an Aeroturbine muffler and TAG. Good price and service. They had the Banks system direct shipped from Gale Banks Eng. The system performs well and you can easily tell the difference in how the engine has just seemed to "uncork" and breathe better. The exhaust and TAG really help the turbo spool up much quicker and easier. With both the Aeroturbine and the Banks mufflers the system sounds a little too subdued though. I wanted to try it this way first but may take the Banks muffler out and just run the A-T. Mainly I wanted the full 4" system from turbo to tip and Banks is it.

 

[Car_nut57]

4" exhaust kit

We have several options so you can reuse your 4" tail pipe and replace the rest of the pipe with 4" using a regular muffler or Aeroturbine. We can even put together a kit with Banks down pipe which elimates the cast elbow. Many options to do this, see our site http://www.dieselpowerproducts.com/exhaust or give us a call to discuus what you are looking for.

 

[ACerf]

4" exhaust

Since I have a Calif special, with a CAT. I spoke to the folks at Speedway Muffler in Fontana Calif. They told me they could widen the inlet & outlet to go to 4" pipe from Turbo to Muffler. According to Sparky at Speedway they have some sort of special tool to open the CAT openings. The cost for the mod and piping; about $250. I guess they have been doing this for some time now with great sucess, and improved performance.

 

[DocDetonancour]

Does the Banks give any HP, Torque, or MPG gain? What does it sell for about? Thanks, Doc

 

[DPKetchum]

Banks claims 18h. p. improvement. I saw a instant 1 to 2 mpg increase.

 

[Big MAK]

All the 3rd Gen are 3. 5 for a ways past the turbo; then expand to 4 -- I think after the muffler; I don't remember for sure now. But the same thing essentially -- 3. 5 from the turbo then 4 -- not 4 inch all the way.

 

[Zer0hmZ]

Hi guys, forgive me if my questions below are ignorant, but I just wanna get something straight.



Based on the comments here, would it be better to replace the muffler with something "nicer" or all the piping. If I replace all the piping though, it seems it doesn't make a big difference since:

Originally posted by RDietze

that is exactly right. i also installed the banks and after inspecting the turbine from under the truck, i noticed the turbine is about 1. 5" in diameter (at the discharge into the exhaust plumbing) -- the "new" restriction for me now has become the hy35 turbo.

If I replace the muffler besides sounding (hopefully) nicer, will it to anything else performance-wise?

 

[DPKetchum]

The WHOLE exhaust system is restrictive. I would replace the whole deal from Turbo back if you want a performance and mpg improvement. If only a NOISE difference muffler only I guess.

 

[Blakers]

Originally posted by DPKetchum

The WHOLE exhaust system is restrictive. I would replace the whole deal from Turbo back if you want a performance and mpg improvement. If only a NOISE difference muffler only I guess.

Why is it restrictive behind the muffler if it's all 4 inch? Personally I can't see where 3. 5 inch is restrictive, unless you're running some 500 hp or something. My 95 was around 400 horse and it had a 3 inch exhaust the whole way and very controlable egt.



I'm going to replace my muffler with a 4" straight through as I know they are restrictive. My cousin gained a lot by just doing that. But I really can't see where the rest of the exhaust is restrictive.

 

[ACerf]

Passed the Muffler it is Mendel bent, why replace it! You can not bend most piping that is 3. 5" with a pipe bender. I would replace the 3. 5 up to the muffler and install the AeroTurbine in its place.