open header hp/trq loss?
 

Anyone know what the power drop is when you run an open header on an accent at the track?

Whyyyyy? Go get an exhaust made...

Of all my setups open header was the quickest. It was also totally f*cking annoying.

Idk if it has been dyno tested, but I'm sure that you wouldn't get that many scavenging gains by putting on anything but a straight pipe.

You will Lose power.



Most accent have 2 Sensors. Pre and Past.



The First Does the mixture of fuel and monitor how much is burned (normaly fitted Before the Cat)

The Second is after the cat. (monitors how rich the mix is to back off the fuel for a better air to fuel mixture.



If u remove ur exhuast. You will run Rich causing your engine will run default and Rich to keep the car running. Long periods of this will build up alot of carbon and cause Valve seating issues and then lose engine pressure.



Not recommended.

Second O2 sensor (US market anyways) only verifies function of catalytic converter. Does not get taken into account for fuel trims.

As far as not running as 02's or just 1, Most of the time the ECU will run in open loop and run rich. Which can actually increase power....



One thing no one thinks about is, that because the exhaust is so loud and its pulsing by the engine. I believe the power loss is from the engine retarding the timing due to the loud pulses the engine might think that it is actually knocking. When you run the pipe back to a muffler even aft mkt. ITs smoothed and not as loud.

No, knock sensors are accurate enough to detect only knocking, as it comes back at the natural frequency of the engine block. If your individual exhaust pulses are slamming into the back of the exhaust valve with enough power to vibrate the engine block... I want your exhaust!

Well the idea, came from a turbo book I read, where when driving a car on a gravel road that the engine thinks that it is knocking and retards timing, I assumed a open header pulses could possibly do the same thing.

It is a valid concern, but knock sensors are accurate enough these days that you needn't worry. That said, I doubt it would be hard nor expensive to wire up a knock light...