FYI new muffler+dumped added torque!!!

Some exhaust mufflers have been known to cause a loss of power (Flowmaster), and some have given small gains. "Back Pressure" is an old timers term, and came about when engines had pushrods, and engineers had no way to time the exhaust pulses (scavenging), as they do today. Now days, Intakes and exhaust systems are engineered (tuned) to make the engine run as efficiently as possible for economy, and performance. Changing one, the other, or both, can have negative affects. If you look at dyno sheets from manufactures, you will see that most start at around 3k rpm. This is because they dont want to show you the loss of low end power their systems gave. And as I have mentioned in other postings, you CAN have a gain with a muffler change. Most Ive seen on these trucks is 8 hp. Hardly enough to make the difference between a dog, and a tire burner. And those gains I have seen are "Peak" gains. "Peak" meaning the largest difference between the stock curve, and the modded one. It does not mean at max RPM's. Most all of these mufflers have had a 2 HP or so loss of low end, until about 2000 to 2500 rpm's. Some things I have learned thru trials and errors are, Loud doesnt always mean more power. Larger exhaust diameter can actually hurt performance. People fail to look at the size of the OEM muffler. Its huge. BUT.....It flows quite well. A smaller muffler doesnt mean your getting more power. Nor does a louder one.

 

Ya know....they make pills to help you.....

 

To add:
To make a thread claiming "added torque", with only a butt dyno for proof.....what did you expect? No one is bashing you, just debating.

 

You werent being "helpfull" by claiming your butt felt more power. Now....If you dunoed it, and posted the results, then thats helpfull. And......most folks on here know better.