Long story short, you don’t need or want back pressure in an exhaust. You want low back pressure and high exhaust velocity at the same time. If you increase the exhaust tube diameter, the back pressure decreases but the exhaust velocity decreases too. You have to find a sweet spot somewhere inbetween, where the exhaust velocity is high enough but the back pressure is still acceptably low.
Only if I need a back massage
what about a turbo diesel car? like a bmw 320d, after decat, if i remove all the muffelrs and mid box will the power be better ?
To explain, cutting off your exhaust at the headers won’t really make your car faster, Honda drivers and high schoolers take note
Oh really? So why do all the professional drag racing teams racing honda’s use a hood-exit exhaust?
NA cars do need some of it. Back pressure gives some torque to these engines, while reducing top HP a bit. If it’s a turbo, then throw it all out. Bigger and ‘straighter’ pipes give the most effect to those. Turbo creates backpressure. Pipe diameter is subject to diminishing returns. We stopped at 3 inches for our project.
Them dislikes 😂😂😂😂
For carbureted cars it does matter, otherwise the cylinder will not fill with air.
Depends on the application. Your average 4pot NA needs some. Just take a look at the MCM Exhaust Myth Busted video for reference. Pink was stock, blue was a straight pipe with a potato in the exhaust
As someone in the comments said: the potato works like a golf ball’s dimples: one form of turbulence is created to help negate a more disruptive form of turbulence
is there a site or program to work out the correct system for my car?
O
No. You do need some things that result in you running with some backpressure though, like pulse tuning and high enough velocity to scavenge with.
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Do I?
Long story short, you don’t need or want back pressure in an exhaust. You want low back pressure and high exhaust velocity at the same time. If you increase the exhaust tube diameter, the back pressure decreases but the exhaust velocity decreases too. You have to find a sweet spot somewhere inbetween, where the exhaust velocity is high enough but the back pressure is still acceptably low.
Only if I need a back massage
what about a turbo diesel car? like a bmw 320d, after decat, if i remove all the muffelrs and mid box will the power be better ?
To explain, cutting off your exhaust at the headers won’t really make your car faster, Honda drivers and high schoolers take note
Oh really?
So why do all the professional drag racing teams racing honda’s use a hood-exit exhaust?
NA cars do need some of it. Back pressure gives some torque to these engines, while reducing top HP a bit.
If it’s a turbo, then throw it all out. Bigger and ‘straighter’ pipes give the most effect to those. Turbo creates backpressure. Pipe diameter is subject to diminishing returns. We stopped at 3 inches for our project.
Them dislikes 😂😂😂😂
For carbureted cars it does matter, otherwise the cylinder will not fill with air.
Depends on the application. Your average 4pot NA needs some. Just take a look at the MCM Exhaust Myth Busted video for reference. Pink was stock, blue was a straight pipe with a potato in the exhaust
As someone in the comments said: the potato works like a golf ball’s dimples: one form of turbulence is created to help negate a more disruptive form of turbulence
is there a site or program to work out the correct system for my car?
O
No.
You do need some things that result in you running with some backpressure though, like pulse tuning and high enough velocity to scavenge with.