free DIY better flowing stock exhaust.
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From: From Ohio, now in N. Virginia
yeah, opening the flapper would make the exhaust louder.
I heard a Golf R32 guy who removed his flapper on his stock exhaust. All other piping on his car was stock and untouched. It def sounded very aftermarket when he was on the gas. At idle it sounded very stock. However, I have to admit on the R32 the sound was almost ricey...not like bumblebee ricey...def a bit deeper but not as deep as an aftermarket exhaust would be...but then again this was on a R32.. just my 2 cents.
good luck with the mod.
I heard a Golf R32 guy who removed his flapper on his stock exhaust. All other piping on his car was stock and untouched. It def sounded very aftermarket when he was on the gas. At idle it sounded very stock. However, I have to admit on the R32 the sound was almost ricey...not like bumblebee ricey...def a bit deeper but not as deep as an aftermarket exhaust would be...but then again this was on a R32.. just my 2 cents.
good luck with the mod.
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Joined: Aug 2003
Posts: 554
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From: Durham, NC
I've always heard that there is a benefit to the flapper: low end torque.
Some will argue that backpressure created by the flapper is not good on a turbo car, but the flapper only stays closed at low RPMs. By the time the turbo spools and you've lost the benefit of any backpressure, the flapper is wide open.
Anyone else have any thoughts on this?
Cabo
Some will argue that backpressure created by the flapper is not good on a turbo car, but the flapper only stays closed at low RPMs. By the time the turbo spools and you've lost the benefit of any backpressure, the flapper is wide open.
Anyone else have any thoughts on this?
Cabo
Originally Posted by kuniboy
Allright, for those of you that can't afford an exhaust system yet, this DIY is for you. As we know that Evo exhaust has a flapper door inside the muffler to control backpressure. The door opens at higher RPM. So, why don't we keep it open for better flow? Here's how! Keep the flapper door open with a long screwdriver. Take a drill, and drill through the muffler and the door in a straight line. Finally, attach a screw to the muffler and the door to keep it open. That's it! Now, this is just one of those , you're bored as hell and have nothing to do project. For those of you that has **** to say about this, please keep it to your self. 
Just trying to help!
Just trying to help!
Originally Posted by alex_alex
What kind **** sh-t is that? Everyone should be allowed to voice their opinion about this DIY. They may have discovered some long term effects or other concerns that you don't know about.
You guys are funny.
.
Too broke right now to get a catback so I decided to do this mod. Furthermore Al said that with my current setup - cams, MBC, hks rs, dp, catdelet, fp, custom tuned - the stock CB was blocking gasses to the point of knock at high rpms.
I took a different route, I drilled a hole in the muffler and flapper and carefully fished a piece of aircraft safety wire with a knot through each pulling it tight and after 45 min, it was done.
Car runs and boosts better for me but I doubt doing it will help stock evos.
Thanks for the idea, it will get me by for awhile til I get a CB
FYI Exhaust restriction is employed to control HP to desired levels in some racing events.
I took a different route, I drilled a hole in the muffler and flapper and carefully fished a piece of aircraft safety wire with a knot through each pulling it tight and after 45 min, it was done.
Car runs and boosts better for me but I doubt doing it will help stock evos.
Thanks for the idea, it will get me by for awhile til I get a CB
FYI Exhaust restriction is employed to control HP to desired levels in some racing events.
A FYI.
The EVO IX's do not have the same type of exhaust.
They do not have a valve. They have a perforated tube.
What you can do is hack away at the perforations...sort of connect the dots so that the opening is bigger.
The EVO IX's do not have the same type of exhaust.
They do not have a valve. They have a perforated tube.
What you can do is hack away at the perforations...sort of connect the dots so that the opening is bigger.
