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jj141979 · 04-15-2014, 08:21 AM

Quote:

Originally Posted by Fast0ne

You need to do more research. Back pressure is a myth.
Exhaust: The straight scoop on backpressure - DSM Forums

exhaustbackpressure

Theres also conflicting reports and test done that states the exact oppisite! Who or what study do u believe??? I believe in the backpressure "myth" because my exhaust broke one time right before the cat while i was towing through west virginia and other than the sound i knew right away what had happened.......i lost all my back pressure and the truck was not pulling like it was minutes prior to the exhaust giving out. I was running over 4000 rpms alot more than i did before the exhaust broke! I finally got it fixed right before i left west virginia and it towed alot better! That is enough research for me! Gasoline motors need some back pressure........if i want higher torque at lower rpm!!!!!

Fast0ne · 04-15-2014, 09:12 AM

I guess you did not read any of the post they explain in detail what you were experiencing. If you would like me to post more back pressure is a myth I will. There are no conflicting results sorry it is what it is.

jj141979 · 04-15-2014, 12:03 PM

Quote:

Originally Posted by Fast0ne

I guess you did not read any of the post they explain in detail what you were experiencing. If you would like me to post more back pressure is a myth I will. There are no conflicting results sorry it is what it is.

So the loss of of torque has nothing to do with the loss of backpressure but everything to do with gas velocity.......Ill give ya that! But if make the exhaust less resrictive the "gas velocity" will be slower hence dropping torque!! So we both are right!!! Hahahaha!

DanFromGC · 04-15-2014, 12:39 PM

Very educational!

Fast0ne · 04-15-2014, 01:25 PM

You won't loose tourqe.

I am going to see if I can find my dyno sheet so I can show you power and torque gain after a cat back exhaust was installed. Any exhaust that you will find that they all show power and torque at the upper rpm range.

jj141979 · 04-15-2014, 01:51 PM

Ur right......u will hain torque at the upper end of the rpm range.....but u loose some at the lower end. Thats what im trying to say.

Fast0ne · 04-15-2014, 03:08 PM

Wow trying to get you to understand anything is like banging my head against a wall.

Please learn to read and understand the way a engine and exhaust system work. I have given you some reading material to learn. There is the whole internet that you can learn more from. Type in the google search bar back pressure myth. All you keep coming back with is when you exhaust broke and you lost all your torque. If you really really were reading the links I posted you would understand why you had issues.

To the original poster if you run a cat back exhaust just buy from a good name company. And sorry for clogging up your post.

TDI-Minnie · 04-16-2014, 06:29 AM

With the Cat still in place, any muffler swap by itself will show minimal gains. The key is what kind of sound it makes... that's why it's a tuned exhaust. There are well designed mufflers that use the sound waves well to enhance exhaust scavenging. Poorly designed mufflers that are not specific to your engine/system will cause annoying droning in the cab and not perform any better because the sound waves in the exhaust bounce back upstream against the flow.
More air out needs to be supplemented by more air in (intake) more fuel (tuner or carb re-jetting) and better air flow in the engine (cams etc.).

They are exhaust systems, not just mufflers.

With all that said, the manufacturers invest a lot in developing their exhaust systems to their specific car/truck. The reason the OEM mufflers are so huge and heavy is because they are efficient, work well and are quiet. It takes a big muffler to baffle AND flow freely.