Stock exhaust and no muffler or 4 inch?

[HOSS]

Ok I just had my muffler and resonator wacked. Would I be gaining anything (ie reduced EGT's) by switching to a 4 inch Stan's header exhaust? I love the sound and feel of the truck now so is it worth it to spend another $600. 00 on a whole new system? Have any of you done both and which do you prefer? Thank's in advance for any thoughts on the matter.

 

[Steve Campbell]

Depending on your fueling level...

Some say below 350 HP it is not necessary. Well there are a lot of things not "necessary" in this life. How hot is your exhaust? There was quite a debated thread by Ted Janetty about 3-4 months ago about "real world" gains by going to 4''. Others say your $600 could be spent better (more Bomb for the buck) elsewhere.

 

[HOSS]

Steve,

No pyro as yet that is why I was looking for help with a comparison between the two types of exhaust. Yes a guage is in the near future. As well as fuel pressure (on my 2nd lift pump) and boost.

 

[Steve Campbell]

Looking at your sig...

... your EGT's should be within reason. The EZ helps with temps unless "lugged". Fuel pressure guage is a "good" idea. I located a 4601 Carter back by the tank (after using same in original lift pump position for 15,000 miles) and really like the constant fuel pressure readings (I have it regulated out of the pre filter port to 10 PSI). I pretty much use the guage to tell me when to change my filter now.



Tell me more about your "ride rite" air bags.

 

[HOSS]

I have mine mounted on the inside of the springs instead of on top so I did not have to cut my inner fenderwell to install. they work great! I run them at 20psi empty and 50psi with the camper and horse trailer. I maintain stock or better ride height and it handles excellent. I only wish I could find a set for the front to level the truck with. They really help with the side to side sway while loaded, it is almost non exsistant. I highly recomend them.

 

[Joseph Donnelly]

I don't find an improvement from 4" vs. 3" with low restriction muffler (or none) until going to the HX40. with 3" the restrictions are the exhaust turbine housing size, and the pinwheel/outlet of the housing. the housing outlet is a bit under 2. 5" diameter.

In summary, I suggest that above about 330-350 hp, get the HX40 which will work best with 4". Around 570+ hp, the HX55 with 5" exhaust is nice

 

[HOSS]

Joseph,

Forgive my lack of knowlage on the subject but what exactly is a HX40? Also, in your opinion would it be safe to go to DD2's with this setup (see signature) plus gauges? Judging by your signature I would value your opinion.



Steve,

What kind of pressure would you need to see to decide to change the filter? What does it run at idle and wot? Did you have any install problems? I am interested in installing a similar setup it sounds first class.





Thanks for all the good information guys!

 

[Joseph Donnelly]

The HX40 is the next bigger turbo than the HX35. The 40 comes set up for a 4" pipe; the outlet is 3-1/4" diameter going to the pipe.



The low restriction 3" setup is good to about 330-350 hp. Should be OK with DD2s. Over 350 hp, even with the 16 or 18. 5 cm2 turbine housing, egt's can get too high.

 

[TomGolden]

HOSS,



First of all, Joe Donnelly is one of the most knowledgeable and highly respected TDR members we have. He has put in countless zillions of hours in R&D on many, many parts on our trucks, from clutches, to cam shafts, to turbos, to injectors, to... ... . He also has I believe the highest horsepower Cummins on #2 alone. At least for a daily driver truck. He is a tad biased towards the 12 valve trucks though



I have an HX40 turbo and the 4" Jardine exhaust. Their cost is I believe $435. It requires no welding. If you order it straight piped, with no muffler, they might cut the price a bit, I am only speculating about that. I recently had them send me a small section of straight pipe to eliminate my muffler. Oh man!!!! Do I love the sound of my truck now



Tom

 

[JohnE]

Hoss;

There is another source just a little further south than Auburn. Rip Rook of

<a href=http://www.protintnw.com/sa-main.htm target=_blank>Source Automotive</a> has some very nice prices and satisfied customers.





diesel on

-John

 

[MikeR]

I ran a 3" straight pipe on my truck with the stock HX35 turbo and 400hp with no egt problems. The only times I would see 1400+ temps is on the dyno or at the track, other than that my normal daily routine and towing was just fine. I had to install a 4" exhaust (this time w/muffler) only because I installed an HX40 turbo. the sound is just as loud, only with a deeper and slightly less raspy tone.



I have always said don't bother on a 4" unless you are going for 350+hp. You'll see the same benefit with a performance muffler or straight pipe.

If you are after 'the sound', then yes, get what you want.



-Mike