swensicle

Well, regardless of what the dyno might say, or however many people avoid where the torque curve lies, there is no doubt that my car has suffered a power loss. I'll be re-routing the new tips tomorrow and will report any changes after that.

Triisomy21

I suggest some of you read this post here. I posted it in the 4.6 section and still keep it handy every time the phrase backpressure gets mis-used.

There's a difference between backpressure and exhuast velocity.

Read up, you might learn something. I did https://mustangforums.com/m_1789889/tm.htm

Virgule

What's confusing here is that it makes sense to use large pipes and flow through mufflers to "reduce backpressure", but what you are actually doing is "reducing exhaust velocity", which is where the "power loss" perception comes from. A well tuned exhaust system minimizes backpressure but maximizes exhaust velocity, which almost sounds contradictory when in the same breath, we are saying smaller diameter pipes are better!

swensicle

That's craziness. Great post! I finished my exhaust yesterday and the addition of a couple feet of pipe and some tips not only made the car sound wicked awesome and a lot more refined, but I do notice a increase in power now that the exhaust is complete. Whether that be from velocity or backpressure doesn't matter a whole lot to me, it's the fact that one can notice a difference in power from what seems to be such a small difference.

viking396

Fire your butt dyno, the sound makes you feel as if you've lost power but you haven't. When I installed my MAC's it "felt" slower but the car ran the same times at the track, when I ran no mufflers for the heck of it prior to the install it ran the same times so...... fire your butt dyno.

MikeVistaBlue06

+1

Maximizing flow in a system goes along with what I said about sonic nodes causing backpressure. Any system that is impedence matched will not have these sonic nodes of backpressure; i.e. in a resonant condition will satisfy maximum transfer of fluid thus in this case maximizing exhaust flow and exhaust velocity.

Same thing happens when you have an 8 ohm receiver and match 8 ohm speakers to it; maximum current flows thus you get max power transfer to the speaker. Same as having your standing wave ratio on a transmitter at 1.00 as well! With the SWR at 1.00 there is no reflected power when you transmit. Reflected power can be thought of in the same sense as these sonic nodes of backpressure--aka a sonic wave reflected backwards such that it hinders the flow! Now that is exactly how you get "backpressure" by installing pipes that are too big or removing components that throws the system out of resonance. Think of it as reflected power!

Fluid flow and electrical current can be understood in the same terms!

Good ole physics!

Mike

swensicle

Haha....I might have to fire my butt dyno, but while your times are still the same, all I was basically saying is that the low-end felt a but less responsive.

firemaker117

Since I installed the SLP loudmouths, I've haven't noticed much power difference, but she accelerates in 5th better and my gas mileage has improved.

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