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Feels like I'm losing power

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Old Dec 8, 2013 | 01:51 PM
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Default Feels like I'm losing power

I just installed kooks 1-3/4" LT's, ORY, with an adjustable Borla cat back, I've got an electric cutout instead of one of the adjustable plates. My question is with the cutout wide open (free flowing out of the tailpipe) would the car lose power? When I close the cutout the car seems to have more power. I just expected with more flow the car would have more power. I haven't brought the car to the track yet so I'm just going off of the seat of the pants right now.
I haven't gotten a tune yet because I plan on doing H/C soon. Just trying to see if it's normal to have less power with the cutout open.
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Old Dec 8, 2013 | 03:36 PM
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I bet the sound difference is tricking you to think you are not accelerating as fast as when it it shut and quite
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Old Dec 8, 2013 | 03:40 PM
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My stock stalled a4 with 3.27's lost e.t. at the track. If I had a gear I would have expected gains, however.
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Old Dec 8, 2013 | 04:14 PM
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Originally Posted by ds98formula
I bet the sound difference is tricking you to think you are not accelerating as fast as when it it shut and quite

I'm thinking/hoping the same thing because there's a huge sound difference.
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Old Dec 8, 2013 | 04:19 PM
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Originally Posted by flattusmaximus78
My stock stalled a4 with 3.27's lost e.t. at the track. If I had a gear I would have expected gains, however.
So you lost et with LT's ORY setup? What are your mods?
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Old Dec 8, 2013 | 05:50 PM
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I have a cutout and made 400 to the wheels with it open and 395 with it closed. Back pressure makes it feel like you are pulling harder.
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Old Dec 8, 2013 | 09:07 PM
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Originally Posted by z28SSilvest
I have a cutout and made 400 to the wheels with it open and 395 with it closed. Back pressure makes it feel like you are pulling harder.
So can you feel a difference with the cutout open vs closed. Or is it noticeable at all. Sounds like we the same exhaust setup.
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Old Dec 8, 2013 | 09:09 PM
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Originally Posted by ds98formula
I bet the sound difference is tricking you to think you are not accelerating as fast as when it it shut and quite
this ^
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Old Dec 9, 2013 | 12:17 PM
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Originally Posted by NolaTA
So can you feel a difference with the cutout open vs closed. Or is it noticeable at all. Sounds like we the same exhaust setup.
It is an extremely small difference. I did the e-cutout only for the sound and so I could hear the cam better. I would get an electric cutout though regardless of the power, they really open the car up especially at WOT!
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Old Dec 9, 2013 | 02:40 PM
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Originally Posted by NolaTA
So you lost et with LT's ORY setup? What are your mods?
I had those mods, but I didn't suggest that. When I opened my cutout with those mods I lost et.
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Old Dec 9, 2013 | 03:39 PM
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When i put my headers on, I drove it a couple blocks and went WOT with them open a couple of times and felt as if my car wasn't really going that fast. The noise is very deceiving, and makes you feel slower. Something you will get use to over time but i doubt you are losing power with the cutout open
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Old Dec 10, 2013 | 01:26 PM
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Depending on how well tuned you are, the cutout can
put you into ping / KR - the timing table needs to be
right in places you don't hit, ever, with the cutout closed.
The better mixture in the hole, from better cylinder filling
(follows better sylinder emptying) may also move ideal
fueling from where you were and what common wisdom
says about where to start.

All airflow mods change stuff, cutout is no exception.

But your butt is an inferior instrument for performance
assessment.
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Old Dec 10, 2013 | 07:50 PM
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Mine feels slower as well with the cutout open. It is the loss of low end torque you feel with it open. My car is a little slower 60' at the track with it open, but et and mph are better with it open. Now fill the cylinders with nitrous and it's faster with it open everywhere. But nitrous likes free flowing exhaust.
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Old Dec 10, 2013 | 09:32 PM
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Originally Posted by jblankenship
Mine feels slower as well with the cutout open. It is the loss of low end torque you feel with it open. My car is a little slower 60' at the track with it open, but et and mph are better with it open. Now fill the cylinders with nitrous and it's faster with it open everywhere. But nitrous likes free flowing exhaust.

Yeah I've got a 100 shot on it but I haven't sprayed it since the install, I'll have to see how it feels on spray.
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Old Dec 10, 2013 | 09:59 PM
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sometimes you loose to much backpressure which makes you loose some power so yea having the cutout closed can make a little power than haaving it open sometimes
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