2nd Gen Non-Engine/Transmission 4" Exhaust Question??

[Sparky10]

I am thinking about adding a 4" exhaust to my truck this spring and have been researching the different brands. I pull a 5th wheel trailer approx. 10,000 lbs. with a 2500 Ram. All of the brands claim they can lower the exhaust temp by anywhere from 200 - 500 degrees. That is what I am looking for.

My questions are these:



1) Where are they taking the temperature readings from?



My EGT probe is pre-turbo in the manifold.



2) Will a larger 4" exhaust show lower temp. readings there too? If so why?



You guys have always been great on giving information and I could use a little help on this one. I have written to all of the different dealers and brands and none of them have given me an answer to these questions yet.



Thanks for any info & help!

Scott

 

[Coalsmoke]

Most likely they took the temp readings from the exhaust manifold a few inches from the ports (pre turbo). this should theoretically give them a greater range to play with which means they could show a greater loss of EGT = better for their addvertising claims. Generally, if your EGT's are going to be lower, than they should appear so regardles of the probe being pre / post turbo. the big battle between the two positions was really based on the fact that pre-turbo shows the higher value, making it a more accurate example of what your EGT is.

 

[Bob Wagner]

where did you read about those kind of temperature drops by 4" exhaust alone?



want to buy a bridge?

 

[y-knot]

Oh yell mine droped between 350-600 degrees when I installed the 4" exhaust system. And I picked up about 5-7 mpg at least. The performance went stright throw the roof, I can't drive anymore in the rain or on gravel roads, the thing just sits there and spins, heck it's the best bolt on I ever tried,Not. They can tell you anything they want to, but it's up to you to read between the lines and use a certain amout of comon sence. It would not matter where they sample the temperatures from, pre or post. If there was a drop it would be reflected in either one. I think most people are full of ****z when they tell you they picked up any performance after a exhaust system up-grade. The truth is they have a louder truck, so it must be making more power and going faster, Right? I never seen any benifit after the exhaust system, and if anything I lost fuel mileage. Truth is, I think I liked it better when it had the stock system and no muffler.

 

[esommer2500]

The decreases in EGT's you MAY see will depend greatly on the BOMB's your truck may or may not have. As power is increased, the engine needs to breathe better to control EGT's with the increased fuel, hence air intake and exhaust additions.



Air+Fuel=Power, so you need to get air in, but also need to get rid of it as efficiently as possible, with minimal restriction as fuel is increased.



If you're not heavy on fueling and don't plan to be, you might be better off just getting a Geno's muffler eliminator kit and save a bunch of money, as 3" can be efficient to something like 350 hp.



FWIW.



Eric

 

[Mark Craig]

Exhaust Questions

Sparky10,



Most exhaust suppliers ( it's the only place we will take it) will take the EGT reading Pre Turbo !! We quote up to 200 degrees reduction which is a real and viable amount, anyone that tells you 200-500 degrees is really not being to up front with you. You will get a lower EGT reading pre turbo when you go to a 4 inch system as the backpressure is removed, the turbo can spool up faster (more power sooner) and the intake side can work more efficiently as well too. There are HP and torque gains to be had and some customers report MPG improvements as well. Call us if you need any tech info.



Mark @ DPPI

 

[Coalsmoke]

y-knot,

given the right exhaust system, it can be benificial. What usually isn't very benificial is when people go out and buy a couple of mismatched pieces and slap them on, get a loud sound and think they have performance exhaust (this includes flowmasters, which sound cool but aren't too functional). I increased the power on my T-bird by 23HP when I had custom exhaust built for it.

 

[Sageair]

As a folow up question if my H/O already has 3 1/2 inch exhaust I imagine the benefits of going to 4 inch would be negligible to non-existent. I am stock now , may someday do an EZ. Am I correct in my thinking or am I all fouled up? Wife will of course say I'm AFU without even hearing the question.