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I have a momentary switch in the large blank location next to the traction control button to control it. It takes approximately 7-10 sec. to go from fully closed to fully open. And in all honesty its actually a very old design. Street racers in the 1950s were using cutouts to have loud racing exhaust systems that would have optimum flow and velocity(i.e. side pipes on a race car does the same thing without the valve), all while being able to keep the police off their backs from the cars being too loud. Back then they used bicycle brake cables to open the valves though. I just modified this concept to work with my application. To see how it works inside the engine I've found that a hookah works really well to explain it. If you hold to hose straight and inhale as hard as you can and watch the speed of the bubbles. Then hold the hose at a 90 degree angle and inhale as hard as you can again. When held at a 90 degree angle the movement of the bubbles clearly doubles in speed and the amount of smoke that you are able to exhale is far heavier even on a shorter inhale length. Its kind of a backyard way to test the theory but it works. I've also spent a lot of time reading on how to maximize exhaust efficiency for power gains. Plus I figured if it didnt work the whole setup only cost me $250 and a 6 pack of MGD so if it didnt work I could always get my cat and resonator rewelded in and eventually get the CS catback and it would be no harm no foul.
 

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I have a momentary switch in the large blank location next to the traction control button to control it. It takes approximately 7-10 sec. to go from fully closed to fully open.

I've also spent a lot of time reading on how to maximize exhaust efficiency for power gains.
Hard to tell what your actual intent is here. Are you intending to use it as an actual cut-out they way they are supposed to be used? i.e. open it and go.... Or are you trying to manage the cut-out valve like a power-valve system? i.e. managed valve opening/closing based on engine speed.
 

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I have a momentary switch in the large blank location next to the traction control button to control it. It takes approximately 7-10 sec. to go from fully closed to fully open. And in all honesty its actually a very old design. Street racers in the 1950s were using cutouts to have loud racing exhaust systems that would have optimum flow and velocity(i.e. side pipes on a race car does the same thing without the valve), all while being able to keep the police off their backs from the cars being too loud. Back then they used bicycle brake cables to open the valves though. I just modified this concept to work with my application. To see how it works inside the engine I've found that a hookah works really well to explain it. If you hold to hose straight and inhale as hard as you can and watch the speed of the bubbles. Then hold the hose at a 90 degree angle and inhale as hard as you can again. When held at a 90 degree angle the movement of the bubbles clearly doubles in speed and the amount of smoke that you are able to exhale is far heavier even on a shorter inhale length. Its kind of a backyard way to test the theory but it works. I've also spent a lot of time reading on how to maximize exhaust efficiency for power gains. Plus I figured if it didnt work the whole setup only cost me $250 and a 6 pack of MGD so if it didnt work I could always get my cat and resonator rewelded in and eventually get the CS catback and it would be no harm no foul.
Hard to tell what your actual intent is here. Are you intending to use it as an actual cut-out they way they are supposed to be used? i.e. open it and go.... Or are you trying to manage the cut-out valve like a power-valve system? i.e. managed valve opening/closing based on engine speed.
More of a power valve I guess you could say. I can't necessarily use it like a normal cutout open/closed because thats not practical for the application and the range of driving that I do. I live in downtown Chicago but work 30 miles away in the suburbs so my morning commute starts out bumper to bumper hardly going over 20 mph and then I reach a certain point and can instantly accelarate to 80 mph and cruise there. Because the type of driving fluctuates so much the only way for it to work effectively is to drive it and always play with where you have the valve set to get the best balance. wide open is great on the highway at 80 mph, I even see an increase in fuel economy like that but in the city its deffiningly loud and loses too much torque below 2500 rpm to use it without taking off from every light like a jackass just to get some decent torque you have to rev to 2000 rpm before letting out the clutch or the car will bog down. close the valve halfway and this is no longer an issue but at high speed you wouldn't get the full potential of the set up.
 

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Haha I thought about putting an electric cutout on my car. I got 2 brand new ones sitting in my closet but it will probably just sound like shit.
I still dont see how it could have any real gains though. If anything it may gain very little way up top where its not usable power
 

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Discussion Starter #107
Well not sure how a dyno thread turned into an electronic cut out thread. If your setup is so stellar go run it on the dyno, otherwise feel free to put together a build thread and I can move the cut out discussion there.
 

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Well not sure how a dyno thread turned into an electronic cut out thread. If your setup is so stellar go run it on the dyno, otherwise feel free to put together a build thread and I can move the cut out discussion there.
Sorry wasn't trying to ruin your thread just justify my estimation. And the only way its unusable power is if you leave it fully open all the time and have too large a diameter y pipe. You'd have alot of flow but you would lose all of your velocity so the exhaust gasses would stack up and you will lose power through out the entire power band.
 

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In regards to the car from Seattle with the CS Intake and Exhaust.

Stock dyno was 117, intake and exhaust was 130, you're only looking at 13hp increase. (this was done on multiple runs for accuracy).



The addition of the header put us up to 134.5, so you're looking at 17hp based on the those 3 mods, all done on the same day, with multiple pulls done by the same person.

In theory, if you can run the exhaust and header together (because it sounds like a damn race car) and you can get DPTune to update your ECU, you MIGHT be able to pull 140, otherwise it's a dream.

Oh and last time I checked, Seattle was at Sea Level, given that it sits on the Puget Sound. Not that it matters, a 15 minute drive and I can be several thousand feet above sea level.
 

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I had mine dynoed last summer with just a muffler delete. I got 161 whp and 163 wtq. I got dynoed twice, because they couldn't save the files, and still never gave me the files. I plan on going again to see where it is with the intake installed, and possibly after a tune. Btw it was a mustang dyno incase anyone cares.
 
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