longtubes with "quick disconnect" cats

[crcpdx]

Removing the cats, which is a restriction (with no other changes being made) will not affect "where the power is being made", which means the HP/TQ curve. The only thing that will happen is the curve will be the same, only the numbers will increase, even if the increase is only slightly higher.



No, no, and just well..., NO

"Big turbo cars" suffer from turbo lag, which has absolutely nothing in common with removing the cats on an NA car. "big turbos" have more inertia which takes longer for them to spool up, but the upside is bigger turbos will make more HP (because they move more air), only higher up in the rpm range versus a smaller turbo. Sorry, but your comparison involving "big turbo cars" and removing the cats on a NA car is invalid and completely laughable at best.



"Too long to explain" because any explanation on your part would be from a place of ignorance.

In short, the idea of "an engine needs back-pressure to make torque" has been debunked for at least twenty years, and this persistent myth needs to die a quick death.

Any time a restriction in an exhaust system is removed, the engine will make more power and more torque. PERIOD.

 

[crcpdx]

Ok so by your logic we should just throw the whole thing out and run from the header? The turbo lag was to debunk your theory that more air always equals more power everywhere. Not true. You can have a peaky curve with higher hp tq numbers and that doesn't equal more usable power on the street. I can tell you're one of those guys who just loves to argue. So bye Felicia

 

[VooDooDaddy]

Ok so by your logic we should just the whole thing out and run from the header?

WTF? Is English your first language?

The turbo last was to debunk your theory that more air always equals more power everywhere. Not true.

Hey Dummie, go back and read my post. WTF did I write or imply that??

You can have a peaky curve with higher hp tq numbers and that doesn't equal more usable power on the street.

And WTF did I write or imply that??

I can tell you're one of those guys who just loves to argue. So bye Felicia

I don't enjoy arguing, but I do enjoy pointing out that we have peeps on this forum that, from time-to-time, go FULL-RETARD.

My God..., there are some stooooopid Mother-Fornicators on this forum....!!!

 

[Tickitty Tock]

Ok so by your logic we should just throw the whole thing out and run from the header? The turbo lag was to debunk your theory that more air always equals more power everywhere. Not true. You can have a peaky curve with higher hp tq numbers and that doesn't equal more usable power on the street. I can tell you're one of those guys who just loves to argue. So bye Felicia

Don’t feed the trolls bro

 

[cib24]

"I believe people have back pressure confused with something called Delta Pressure. I'll explain:

When the engine is working to draw in air (intake), it must overcome the forces that resist air movement. These forces include things like gravity, air density, internal motor friction, resistance caused by the length and diameter of the tubing used, and the resistance caused by any medium that the air is drawn through such as filters or chemical sorbents. The sum total of all these forces is called backpressure, and it is a measure of how hard the engine has to work. Any time the engine is working, it is always working against some level of backpressure. So, technically, backpressure is the resistance of air flow.

Now, as car enthusiasts, we see that backpressure is resistance and resistance is BAD for performance right? Well, this is where Delta Pressure comes in. Delta pressure describes a pressure drop through a component or a difference in pressure. Delta Pressure is what is needed to basically get exhaust gases out of the cylinder and moving through the exhaust tract for optimum performance. Now, for all the engineers out there, you understand that as a volume of air travels, it's pressure is directly related to it's traveling speed. Therefore, the faster the gases are moving, the more velocity or pressure it has. So, the higher the delta pressure (difference in pressure within the engine, the faster the gases will move through the exhaust tract.

Exhaust gases have to travel a certain speed and contain a certain velocity for optimum power production at any given RPM point. A certain delta pressure must be achieved to get the burnt air/fuel (exhaust gases) out of the cylinder on the exhaust stroke. By not having this certain delta P, it affects valve overlap (burnt air/fuel is sucked back into the cylinder on the intake stroke). Now, it is virtually impossible to achieve this certain speed for each and every exact RPM point, so we have to do some sacrificing in order to achieve the best power production. So, lets discuss this regarding exhaust mods. A straight through exhaust (no cats, no muffs) enables exhaust gases to move much quicker than if there were a restrictive exhaust. Now, as I mentioned earlier, each RPM point requires a certain amount of gas velocity for optimum power production.

So by altering the flow in an exhaust tract, you therefore basically affect your powerband, not overall levels of power produced. A free-flowing exhaust will inhibit better upper RPM power than lower-end. But being too restrictive will just increase backpressure (resistance to air flow) and hurt performance.

Straight though mufflers provide higher velocity, as long as you don't go too large with the piping which will allow gases to over-expand slowing down the flow of the exhaust......

Its all about achieving the highest possible speed without causing too much back pressure and too little delta pressure...basically achieving the best balance possible between delta pressure and back pressure...in order to achieve the most hp and tq under the RPM curve."

 

[vincentjm]

I believe he's in Switzerland and they are require to have the factory cats.

Ha, even taking the plastic engine cover off is technically illegal here lol