Sn00ganS1337

Confused about the rumor. If you're taking out the mufflers and replacing them with straight pipes and reducing weight, wouldnt you be making your car faster not slower?

|UCF|chron

yes, about 4-7 hp loss

Sn00ganS1337

so do you suggest getting a custom dyno tune right after I put the exhaust on?

bascho

Does anyone have dyno print-out scans to prove that?

Sherwood06GT

BS

555*

No dyno required for any after cat exhaust. You will need one for LT headers however.

|UCF|chron

lol u and 555 are also in this thread about the exact same thing, thats where i read about the 4-7 hp loss
https://mustangforums.com/m_2087981/tm.htm
but i guess ur right withouthte dyno graphs cant prove or disprove anything

555*

I made a post on TMS, hopefully some of the people who claim this, will chime in with graphs. I'm still skeptical about the loss in HP/TQ but I think that its very well possible due to back pressure physics and all that crap, but I unno. I'll post up if I get any evidence over there.

doode

SLPs are axle back exhausts
just how much back pressure can u lose from that?

bl1nk

There is a huge thread about this from a couple months ago where a few of the forums best car guys (who also happen to be engineers in one thing or another) say that backpressure isnt good and that straight pipes will almost always provide -more- power than chambered systems by allowing the exhaust to flow more freely, providing that the pipes dont get too large because then it will slow down the exit velocity. In other words, straighter, appropriately sized pipes, with less obstacles blocking the exiting of the exhaust fumes are optimal.

Personally I dont believe any axle backs will cause you to lose power, but at the same time it wont cause you to gain power either (under normal N/A conditions.) On a blown system it will certainly be a larger factor to have a more freely flowing exhaust setup.