dumping jardine exhaust

im thinking of dumping my exhaust before the axel. now my question is, will i lose power by doing this? will back pressure lossen up alot? or will it still be the same. also, would i have to worry about possible discoloration or harmful fumes coming into the cab like this?

 

i dont know about the back pressure, but its gonna be a whole lot louder. fumes not so much, only if ur sitting there for a long period of time. i had my magnaflow dumped b4 the axel and hated it. took her back and relocated to dump after the axel. sounds a whole lot better. did notice a change in power. hope this helps.

G

 

was the power a good increase or a bad decrease?

 

My apologize brother, typo. meant to put "didnt". Just a change in sound.

G

 

I have a dump before the axle. Every once in a while it is "annoying" but only if you have a soft voiced female in the passenger seat and you can't hear her. Other than that, the music covers it up for me.



Oops. Don't know if the engine makes much a difference, but you get what I mean anyways right.

 

sounds about right to me

 

stop this line of thinking dude. as I said before in another thread, no amount of backpressure is good. Backpressure is an "oldschool" theory that no longer applies to modern motors with effecient exhaust systems. you want the least amount of backpressure, least amount of restriction, and the highest amount of velocity.

so if your current muffler is restrictive (ie. baffled, chambered, etc.) then removing that component will (in theory) free up a few ponies. But it may be negligable if the system is already very efficient. Meaning the butt dyno will not feel the difference.

 

well, yeah i mean i know all about the scavenging and all that, but i was jsut wondering about the negative side effects of dumping the exhaust. like CO emissions coming into the cab of the truck

 

OakleyTRD has his dumped, and he hasn't had any negative side effects...

 

he has a 4 cyl?

 

No

 

the further back you dump, the less likely it will creap back into the cabin. why not keep what you have?

 

OakleyTRD has a V6, but I'm guessing it's the same concept.

 

well, my current set up, when i put it on i screwed up the angle that the tip is at. so it hangs down at a 45 degree angle and it scrapes on people driveways sometimes. i cant ever haul anything heavy cause i tend to scrape it. I thought about taking it to a shop and having it fixed but i thought this might be anohter cheaper alternative

 

Yeah, I don't see a problem with cutting it.

 

as this is true it also looks for what kind of power you are looking for. think of it like this, without a bigger displacement or f/i then you can only push so much air into the cylinder and less back pressure isnt gonna help until you reach high end revs allowing that air to be pushed in there quicker through the cycles. dont do much to the 4 bangers except a header and high flow cat dumped you wont feel much.

dont dump it before cause then the hot exhaust gases heat up your differential and rear axle.

again this is only personal experience and nothing proven.

my old tc i had 2.5" all the way back and no cats or resonators, lost lots low end but high end romped.

my current setup, dt headers, jardine catback and love the low end power. starts around 2k and you can already feel the torque build up

 

well, im gonna be going with DT shoty headers hopefully this year. so, low end power will be there a little bit as well as top end power. but i think that either way, the truck should( hypothetically) be pushing close to 175 horses or so after headers as well as the other things i have done. but mainly i want the truck to look and sound as good as possible without jeopardizing functionality

 

no matter how you say it, backpressure is bad and a less restrictive exhaust will ALWAYS put out more power.

 

You can't have your cake and eat it to. For example if you were to reduce the backpressure by removing a restrictive muffler, the velocity may go up, but now if you increase the size of the pipe from say 2.5 to 3.5 inches the exhaust velocity will go down (unless I just fell off my rocker). You've just increased the volume of the pipe for a given amount of exhaust gas.

I will agree with the fact the current exhaust systems on many vehicles are much more efficient than past efforts. So most attempts at increasing performance for a normally aspirated engine will not yield huge gains.

After a little searching I found this article on exhaust and backpressure from a mustange forum. Generally, the article states that backpressure is bad, but on pages 5 and 6 they discuss exhaust pipe size and tuning of the tailpipe.

http://www.veryuseful.com/mustang/tech/engine/exhaustScavenging.pdf

 

no thanks, I'll stick with what I've learned from exhaust builders.

what part of this^ are you disagreeing with? or feel its having your cake and eating it too? I never said use the largest pipe size you can stuff under your truck