Jump to content

Modifying exhaust and intake means more HP, what about MPG's?


Recommended Posts

Truck: 2006 Dodge Ram 2500 CumminsOkay, so I was at the truck shop and they have indicated that a S&B intake and an exhaust would give my truck some much added love. However I have been researching the upgrade and have some questions.Goal: Squeak out some better MPG's and if it looks cooler too, sweet!From my research, the 2006 comes with a 4" pipe form the turbo back, hit a muffler, and exits. So at this point since it's all 4 " I am not going to buy a whole new exhaust kit and throw a freeflow muffler (Magnaflow) on there, and down pipe it cause I don't want soot on the back of my camper or camper tie downs.This is the time to offer alternatives, run a resonator only (to get enough back pressure) use a different freeflow muffler........I can definitely be persuaded in different directions. This includes where to terminate the down pipe, or even what down pipe to get. What can I say, I like opinions :)However, I want to ensure that this extra work will actually increase efficiency of the vehicle. Has anyone seen MPG increases with an upgrade like this?Thanks guys, Dave

Link to comment
Share on other sites

I like two strokes. I will leave the back pressure to the sleds.Zero back pressure - Will I encounter reverse exhaust and engine braking when off the accelerator? Like Jake braking??? So the truck won't coast freely??? This may be a dumb question :duh:If I can keep the cab relatively quiet, lets go for throaty.....I mean it's a Cummins power house, let it out right? What kind of sound would a free flow muffler deliver?Fueling mods, I do have a Edge Programmer that is delivering some low boost fueling, so I can play little bit, would a CAI be worth it now?Dave

Link to comment
Share on other sites

I like two strokes. I will leave the back pressure to the sleds. Zero back pressure - Will I encounter reverse exhaust and engine braking when off the accelerator? Like Jake braking??? So the truck won't coast freely??? This may be a dumb question :duh: If I can keep the cab relatively quiet, lets go for throaty.....I mean it's a Cummins power house, let it out right? What kind of sound would a free flow muffler deliver? Fueling mods, I do have a Edge Programmer that is delivering some low boost fueling, so I can play little bit, would a CAI be worth it now? Dave

CIA will give no gain unless you are getting over 450-500 HP, I don't know what cab you have but the bigger the cab the more prone to drone it is with an open exhaust which the resonator helps with, mufflers quiet the exhaust tone but you still get in cab drone. As far as engine braking there are different types, there is an inline exhaust brake that does just that, the flap closes the exhaust flow from the engine and creates a brake via back pressure, then there is an internal engine brake that holds the exhaust valves open "Jakes or Jacobs brakes" which is a brand name like semis have that turn the engine into a compressor that causes braking internally too. On a factory exhaust you will not get enough back pressure to cause a braking effect as I think you are getting at.
Link to comment
Share on other sites

Thank you.I just remember I had an old Ford Explorer ( I prefer not to talk about it) and I had an exhaust leak close to the headers.....it actually kept my car from coasting freely.Was it a huge notice? No, not at all, but it was happening and even though no one else could tell I knew what was happening cause it was my problem child.From what I hear, you recommend the short resonator to give it the throaty sound it deserves. Guess I'll save the CAI for when I replace injectors which will happen at some point, when it's needed. Right? For now I was running a Wicks Air filter....what filter do you recommend?I have the 2500 Mega cab.

Link to comment
Share on other sites

An exhaust leak would not affect coasting unless the exhaust was dragging on the ground lol. Since you have a Mega cab you will definatly want the longer resonator for sure, Even with a long resonator you still get a throaty exhaust sound just like a free flowing muffler like a magnaflow but it will definitely help eliminate the drone you may encounter on that big cab. Wix filter is good the one to use is the one with a 4 inch thick media versus the factory 2 inch thick media. AH64ID has the part # in a few of his posts.

Link to comment
Share on other sites

Stock intake is good to 450-500HP. You can "swiss cheese" the box or do what AH64ID did and add an intake elbow off the bottom of the box. You can also pull the baffles out out the corrugated section of the intake tube. You'll get more trubo whistle doing that.The biggest restriction on a stock truck is the OEM muffler. Ditch that for a straight thru model and call it good. The kitty doesn't restrict flow that much to worry about it. Leave it in case you move where they do testing.The best thing you can do for mileage is to put a raw egg under the throttle pedal...............and don't break it!!!!

Link to comment
Share on other sites

Can you send pics of the elbow airbox or a link? I would be willing to do that! How do you pull baffles out? I like me a good whistle! Going for a long resonator. Grabbing eggs. DT Resonator: Bueno? http://www.amazon.com/OBX-Long-Universal-Straight-Resonator/dp/B008O8SY0I/ref=sr_1_27?ie=UTF8&qid=1368733825&sr=8-27&keywords=exhaust+resonator+4%22 Down turn tip: Can't find a black down turn tip, so I am going to buy a straight steel down turn, powder coat it, and weld it on. I'll be stopping the ceramic coat 2 inches short of the end for weld, and coating the downward cut up into the pipe 3 inches for the nice rolled look.

Link to comment
Share on other sites

Resonator from FTE diesel http://www.ftediesel.com/store/pc/viewCategories.asp?idCategory=7 Thread on CF: http://www.cumminsforum.com/forum/3rd-gen-performance-parts-discussion/426911-2006-5-9-air-intake.html The Second Gens need a bigger AF... yours does not. And is already a CAI. You'll not see any HP or MPG gains. The best thing you can do is find a mild chip or box to fool the timing. Even an Edge EZ or Econo box. My Quadzilla XZT+ (now out of business) I run on Econo mode (only timing) & pick up a mpg.

Link to comment
Share on other sites

I have an Edge CTS programmable tuner.My setup has a slide in 9.5 foot camper in it, Western Wilderness 1979.I have been playing with the settings and find that driving and changing settings based on terrain has been my best mpg ranges. I live in WA state, so when I am in the flats I cruise on 1, rollings hills 2, passes, 3.....watching my EGT's and load % when in overdrive. However, the biggest gains I have seen is when reducing the low boost fueling level to 2....thinking maybe even 1.I had low boost fueling at level 3 and even though the truck ran like an ape, my mileage was about 12 mpg (with the camper) doing 5 over the speed limit 65-75 mph. What can I say, I am 32 years old and got places to be, hahahahah.However I changed the setting to low boost fueling level 2 and saw 15 mpg without changing driving habits. Was there a change in throttle guts/response? Absolutely, but 3X30 is 90 extra miles and even though I may seem eager to get somewhere, I don't have anything to prove.Side Note: I have been on this forum for 3 days, and really stoked to be here. You guys are awesome and thank you for all the great replies and spurring even more enthusiasm with everything.Cheers.Dave

Link to comment
Share on other sites

Wild and Free - Are you at all concerned with that pipe allowing water to suck into the airbox? I guess I ask cause every other air intake I have seen always goes up. Now I don't have plans to mud the truck, but sometimes you never know where you end up going.......I drive a lot of dirt roads too, so dust will be a large and in charge. Your thoughts.I see the cool hose, definitely makes sense. Will pull trigger on that for sure.Flagmanruss - I have the resonator (30") on order and making my custom turn down pipe from a 15" Elbow. I see the muffler (it's HUGE) but there's this Pumpkin looking thing right after the turbo....is that a catalytic converter? Don't I wanna remove that too?Dorkweed - Baffles removed.Gunna be RAD when it's done.,Dave

Link to comment
Share on other sites

  • Moderator

Lots of good info in this thread. The part number for the OEM 4" filter is 53034249AA. With a Home Depot CAI mod ($15) the OEM airbox and filter are good for at least 450 rwhp. With my 2.5 year old, 25K mile (plenty of dust) filter I barely move the filter minder with a 500 rwhp tune. The OEM exhaust is good for 450 rwhp as well, and the muffler is the most restrictive part of it. If you want a different sound that is a different story. Think about mileage driving, you are low on the fuel and trying to maximize it. In this mode the engine is moving very little air so your not pushing the intake or exhaust to anywhere near there limit, so a bigger intake/exhaust isn't going to do anything for you. Personally I think gutting the OEM intake tube is a waste of time. You cannot gut the part that creates turbulent air, so why bother. An Airaid MIT is cheap, effective, and the proper way to do it.

Link to comment
Share on other sites

The PSM is more money, and removes the lower directional vanes which is counter productive IMHO.

I tried the TAG on my 02" Which I believe serves the same purpose as the vanes in the factory intake tube if we are talking about the same thing" and saw zero benefit for it even tried it with 2 different turbos stock and BD super B, I have had the PSM cool hose on for almost 100K miles and it works excellent and still looks like the day I installed it considering my driving conditions that is pretty good. Years ago I read many articles and argument on this and the vast majority came to the same conclusion of its such a minor detail it doesn't make any difference performance wise.
Link to comment
Share on other sites

  • Moderator

I have searched and searched and cannot find it, but Holset said the directional vanes improve turbo efficiency up to 30%. Yes, that IS marketing but it will have some backup to it. I think they will make the most noticeable improvement at low boost/airflow. From a fluid dynamic standpoint I want them in there, they will improve the flow.

Link to comment
Share on other sites

  • Moderator

In my opinion getting rid of the accordion air turbulence creation hose prior to it will help just as much if not more.

The ribs in the hard plastic piece? That's the on that the Airaid MIT removes, and yes the best piece to replace.
Link to comment
Share on other sites

×
×
  • Create New...