5" exhaust, lower EGT????

[jelag]

So I just read an article about using a 5" exhaust and seeing 200* lower EGT when towing a 5er.... I'm a little worried that just that change would drop the EGT that much.... so I thought I'd ask to see if any of you have seen that kind of change...

Thanks for your thoughts...
"

 

[Prairie Dog]

I wen't to a 4" system with a 44" Donaldson muffler and saw about that much on the hills.
Frankly I was astonished since I would have been happy with 100 degrees!

Just keep in mind that a 5" is going to be loud.

 

[jelag]

Gosh I'm thinking my 05 has a stock 4"... maybe I should measure it..

 

[Prairie Dog]

Mine was 3.5 stock and I "think" yours is too (could be wrong). Check to see if yours starts at 3.5 and gets bigger.
For me, going with a 4" and a straight through muffler makes a huge difference in flow numbers.

 

[Bob4x4]

Avoid 5" you will loose torque on a stock trucl

 

[Jim W]

I am not really sure, I am running 5" system on my 08 but I have not really seen this much drop in my truck. Remember you still have the 3.5" reduction at the junction to the manifold then it will open up to a 5" pipe on my truck. I will still see 1000F on my truck when I tow sometimes. Make sense?

Jim W.

 

[Prairie Dog]

Avoid 5" you will loose torque on a stock trucl

I remember reading that in the very first days of third gens.

 

[JJPage]

I installed a 5" MBRP TBE on my 03 when I was running an SPS62 turbo, the increased noise was significant, but did not bother me. It certainly did not drop my egt's by any measurable amount, but I had already installed a 4" downpipe and cast elbow when I replaced the turbo.

I'm not disputing the person claiming that drop, hard to tell what he had previously, and there could be too many variances that would contribute to lower exhaust temps on his application. I would not guess a 5" exhaust would have that kind of drop, unless maybe you are running massive horsepower.

 

[RWherley]

We put a Magniflow 5" system with a flow through muffler on my dads truck, I cant say anything about EGTs but we did see about 1.5mpg increase in mileage over the stock system, as far noise its quitter then my 93 with 4" strait pipe.