the only thing i noticed with my stack was my right foot got heavier. which could mean higer EGT's

 

It wasn't me, but the one guy on the org, 351fifty, can tell you exactly his egt's w/ straight back exhaust and stacks. Take it up with him, not me.

Because there is less backpressure and more area for heat dissipation would be my guess.

As far as the exhaust only being 10hp, I call bs. There are systems by 42dd for Audi's (a 1.8 liter gasser, mind you) that are good for 30hp... you mean to tell me a 7.3 liter diesel is only getting 10 measly *** hp out of a larger, more free flowing exhaust setup? What kind of mileage does your truck get in city and highway driving? Maybe mixed driving?

 

when i first bought it, it was bone stock. i was getting about 16 mixed driving. now i'm still getting about 16 with the mods in my sig. but it runs a hell of alot better. the heat dicipation, it's 8 feet away from the manifold......

 

Yes I mean to tell you that you are not getting more than ten horsepower out of an exhaust...

I get 16-20. You can not and should not compare what an Audi get's with an exhaust to what a Powerstroke Diesel gets... And to clear up an misunderstandings, the turbo creates all the backpressure your engine needs, therefore your hypothesis needs some work. Also, I don't care to take it up with mr. org, you can believe everything he tells you but I won't. I didn't change MPG when going from stock exhaust to 3" dp with 4" dual exhaust... I wonder if mr. org thinks dual exhaust would drop the egt's 2x the amount because there is 2x the exits....

 

As far as being 8ft away from the manifold.. it's called a heat sync. The length and diameter of the pipe relays the heat further and further out until it dies out.

I call bs on a full exhaust only giving 10hp on a 7.3psd. I understand comparing 2 different types of motors and manufacturers is rather silly, nut the point is if a 1.8liter turbo motor can pick up 30hp with an exhaust larger than a stock powerstrokes, that a powerstroke wont gain any hp ditching the same size piping that a 4banger has on it?! Thats ignorant.

351fifty on the org has verified per his pyro the egt drop.. it's not being pulled out of anybodies ***.

 

Ya, When I built my dual exhaust, I was really hoping to get 2x the power of regular straight pipe cuz I had two exits. I surely thought that was going to do it. Also was hoping to gain 6mpg's over the standard 3 that most people get with straight pipe...

Oh, checked out your Org buddy's post... Looks like he had his pyro in the downpipe... Also came across a post over there by a vendor that said "the stacks look and sound better but wont give you any more hp or egt drops than running a straight piped 4" kit"... Now, don't you think if they actually did do those things, He would be telling everybody so he can sell more of them...

Intake and Exhaust are important, but I just don't see them as that important to worry over a few hp gains... You won't notice it. The truck will sound better, that's about it. If you truly think you gained 30hp with your stacks and picked up mpg's, great, but I don't believe everything I read on the box my intake and exhaust came in. And I certainly don't believe a guy that dropped 300* with stacks with his pyro in his downpipe...

The gain from an exhaust comes in that you are removing the flat downpipe and possibly getting rid of a clogged catalytic converter...A 4" exhaust is not that much bigger than your 3.5" factory exhaust and your factory muffler is perfectly fine to run power through.

I gained no noticeable hp from an exhaust and intake, and my mpg's did not change enough to credit them with gaining any fuel efficiency.

 

well if the pyro probe is in the DP, it's probably showing cooler. i wonder why... oh that's right, it's not accurite. it can very a few hundred degrees up or down.

 

When I straight piped mine it had better throttle response and was maybe a hair quicker but im not going to say it gave me 10+hp more. I changed 0 on my mpg. You are taking what you read as the truth.

 

I gained a seat of the pants performance increase as well as better mileage from installing my 5" exhaust and 3" dp fyi.

I'm not taking what I read as the truth.. I"m taking my experience of owning 39 cars as truth.

 

39 CARS or POWERSTROKES' i've owned 3 powerstrokes. 2 OBS, 1 SD. not a dam bit of mileage or performance gains with exhaust, stacks OR out the back.