Exhaust

Twan · Aug 11, 2013

When I went from my stock to full 4" exhaust I seem a 100-200* egt drop running down the road pulling heavy on flat ground. Peak egts I'm not sure of because I didn't want to test how hot it will go.
If I put a 5" on do you think it would help any, has anyone tried it?

Is there a way to check my back pressure to see what it's at to see if it worth trying a 5"?
Thanks.

ajbond · Aug 11, 2013

I haven't heard of any one confirming benefits of a 5" vs a 4". A insight will read ebp but is before the turbo which is where most of bp is coming from one the muff and cst are gone.
what kind of peak egt you seeing. I will hold 1350 on long grades.. it can be done but I am trying to lower..

Vinny07psd · Aug 11, 2013

I've been curious of the same thing, been thinking about a 5 inch system... With no muffler haha

JMart · Aug 11, 2013

You will still have a 4" downpipe if you go up to 5". You saw your big gains before from removing the stock down pipe, muffler, cat and such. I doubt you will see much difference.

06-sixoh · Aug 11, 2013

Did you search this?

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Twan · Aug 11, 2013

06-sixoh said:
Did you search this?

Sent from my iPad using Tapatalk

Yes, it's all talk about performance, and sound. I've read about ever post about it on PSA and PSN.

Twan · Aug 11, 2013

ajbond said:
I haven't heard of any one confirming benefits of a 5" vs a 4". A insight will read ebp but is before the turbo which is where most of bp is coming from one the muff and cst are gone.
what kind of peak egt you seeing. I will hold 1350 on long grades.. it can be done but I am trying to lower..

I can hit 1600 on a tow tune with my 5th wheel if I want to. I set my egt alert at 1350. Pulling flats I hold 1100-1200, 1300 if its windy.

I need to get my insight updated.

ajbond · Aug 11, 2013

I think you have an issue some where. .your egt get hotter when truck down shifts I assume. My truck really opens the vgt when drive pressure goes above 34psi. Top gear I can see 30psi but at 28-3200 rpm truck can't build over 25 psi. With a mtw stg 1 or hybrid the truck would only build 18-23 in lower gears and get that hot.
I have the ability to fool my ebp and this helps..

Twan · Aug 11, 2013

Anything over about 3200 rpms it heats up, and under 2000 it will get up over 1400.
Exhaust side is all good, no leaks, no black. Intake side all looks great, all new boots.
Part of its my right foot, it's come along way since last summer.

Vinny07psd · Aug 11, 2013

Yikes that gettin hot

Twan · Aug 11, 2013

I don't let it over 1400* not wanting to build a new bottom end just yet. Lol.

Vinny07psd · Aug 11, 2013

Ya I agree, I'm gonna be doing water methanol soon, sounds like you might want to as well

Twan · Aug 11, 2013

I've been thinking about it, also thinking about a twin setup.

Vinny07psd · Aug 11, 2013

Ooooh ya I don't have that kind of money haha

ajbond · Aug 11, 2013

My water meth does nothing to cool egt. I have ran 50/50 70/30 and straight water.. I have 3 nozzles plumbed.. all on solenoids. It is the mpg max kit from Snow performance. It seems to me anything that puts drive pressure above the 34psi mark the vgt will go to 15% and build mediocre boost..

Vinny07psd · Aug 11, 2013

My buddy has it on his truck and it dropped 150 degrees and I have on my race truck and it's worked great for me

Twan · Aug 11, 2013

Twins are a pricy option, but there is noting better than passing people in my 6.0!
Has anyone tried to but a waste gate on the uppipes to see if it would help any?

ajbond · Aug 11, 2013

That is what is crazy. . I can feel the power from it but the ecm doesn't like the added back pressure and will lower boost. I am hoping a 10 bladed turbine is the answer but doesn't seem to help Twan any. My best luck has come from fooling the ebp. I might try replacing the maf just to see if there is a difference..