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Discussion Starter #1
So,

Set up. Long tube, 1 3/4
HFC
X pipe( Mid muffler and rear muffler delete )
Solo J's

Today, I installed straight pipes in place of the resonators.
I lost power/torque. Do I need to let the ecm cycle a bit to
correct ? Or, am I screwed? The sound is what I was after.
At 2 K RPM it blasts. Then not until you mash pedal does it
blast loud. Idle is actually more quiet. NO DRONE AT ANY
SPEED. but, like I mentioned, loss of performance right after I
removed those resonators. Do I need to re tune because of what
I did ?
 

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How did you measure the power / torque loss?
 

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Discussion Starter #3
Just by the amount of force I have to push down on the gas pedal without absolutely anything happening... By the pedal just goes down further and further and further and I don't move faster or faster or faster as normal.
 

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You need a supercharger or tarrrrbo
 

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Discussion Starter #5
Might just need to reinstall some resonators to make it run like it did before. Once again, some people have told me that the ECU must adapt and other said that's nonsense.. I guess my question is is it true or is it false, and just because I remove resonators do I need to update the tune that's in the car.?
 

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Re-tune, THEN come back and see what the difference is.

That said, from what I understand, you removed a restriction in the exhaust system and provided more flow. So that loss has taken away from the low end and moved it to the high end. You're probably gonna have to live with it until the computer adjusts (it will), or you tune it, which may or may not make a notable difference. Taking everything else out of consideration, those resonators are essentially a smaller diameter pipe that keeps exhaust pressure higher upstream.

That's why you gotta be careful going after a sound, because like everything in life.... when you make changes to achieve one desired end, there will always be a trade-off. ;)
 

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Discussion Starter #7 (Edited)
Ahhh, . I am always learning these little lessons.

in 20/20 vision, I wouldnt have Micky Moused the Exhaust ,Just bit the bullet and bought a full American Racing System incl, headers. But, I thought I was being slick and saving money,,,, Ha ha the joke is on me :) By the time I x piped it, ordered headers, cats and added tips, and removed pipe, and etc etc, I am into it more than the A/R set up. The welding labor put me over the top. Not to mention I have freaking HF cats welded to the header collectors.... Geeeez.
 

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Sorry to hear about your issues man. Best of luck getting things resolved.
 

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I'm still surprised that it is that noticeable. Are you sure it's not just your mind expecting the louder exhaust to give more "OOMPH" to the car? :D Maybe we could call it the Ear Dyno.

How many mods have you done since the last tune, though?
 

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I doubt you would lose any performance at all, and I doubt the PCM would have to adapt much, if at all. From what I understand, the scavenging effect caused by the sound waves traveling in the header tubes - that effect is stopped at the first "discontinuity" - like the first drastic expansion in the pipe - in most cases the catalytic converters. Anything you do after that should not really affect cylinder filling (within reason of course). Just removing resonators would not do it.

I have always felt that a louder car doesn't feel as fast to me. I think viscerally I'm equating loudness with performance, and I'm expecting a lot more speed from the increase in noise. But that's just me. The only way to tell is before and after dyno sessions. Or perhaps track sessions if you do the DA correction between days....
 

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Discussion Starter #11
To the responders who think that it might be because of an increase in loudness that makes me think I'm losing power; I might have to agree with that theory cuz I have subscribed to it in the past. It could be that effect. Or could be a coincidence that my car is running like crap and I just happened to remove the resonators. Because I've had a long running problem with the car running good for a couple weeks and then running bad for a couple weeks. It just could be in the crappy mode. Time will tell if it perks up again...
 

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Discussion Starter #12 (Edited)
So, ... Talk about a coincidence, it looks like the car isnt running bad because of the resonators deleted. It just so happened that the car was running good before removal, then it went into its crappy mode after removal.( been dealing with this for almost two years now ) Now, back to running great ..... Very good! Its been good for 7 days straight now.

You know, I am thinking that I might have an issue with the tunes transferring into the ecm. EFI Live has updates, and I have noticed weird things when loading. If you have key in first click position, it loads different than if you have key in second click position. I have 5 different tunes that I rotate when I feel like it. One for better off the line but not as good top end, one dod active, one deleted, etc, ..

Im crossing fingers that the wire I posted about from the coil pack ground, has solved the issue I have been chasing for so long. It broke off from ground location.( between head and firewall ) Maybe it was fragile all along and messing performance intermittently.

I also can say with certainty that when the car is running well, the exhaust isnt as loud. When its crappy, the exhaust sound is louder. Its now currently subdued, as it can be with my set up.
 

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Mostly I was joking with the Ear Dyno remark... hehe Hope it sticks.

Glad you've got everything settled for now, and hopefully for a while. :)
 

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Discussion Starter #14
What??? You were joking? Thanks alot! I have been spending two days looking through the internet for an Ear Dyno shop in my area.
But, I really do believe there's a correlation between a louder exhaust in the feeling that your car should now go faster... Haha, imagine how the Tesla drivers feel sometimes! They have the speed but they probably feel like they're going slow..
 

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Well I was just doing the CYA in case you were offended LOL... not really... But anywhoo... I agree with the correlative effect. I was actually a little disappointed when the Solo's quieted down after a few weeks of driving. :D
 
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