butterfly valve

[triple7]

Hey guys, on alot of the exhaust threads (2nd most popular topic it seems) you all talk about the butterfly valve on the stock exhausts. What is it and what does it do? What happens if you get an aftermarket exhaust that dosent have one or dosent use it?

 

[anrkizm95]

its for low end torque.some people wire it open.its made into your stock muffler with an aftermarket pipe you leave the servo under the air box plugged in to keep the engine light off or buy a resistor from asb or use ecmspy or take the servo off and live with the light on.

 

[Jon0341]

Also its on the 12's not the 9's

 

[Stevenc150]

Below is a pic of the valve. With an aftermarket, you generally lose some of the low-end grunt that the stock valve helps - but you can get it all back and then some, with some custom tuning.

 

[triple7]

Wow, I do not want to loose ANY low end. When I get a pipe I want MORE low end. I have an 1125. I am assuming it has one as well?