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Power loss with cut out open??

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Old Aug 8, 2011 | 12:29 AM
  #21  
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What's the AFR and injector duty cycle? Maybe the injectors are on the border line and with the added air from the cutout open they are shutting down.


I would think a tuner would look at those two things pretty quick after a power loss that big.
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Old Aug 8, 2011 | 01:41 AM
  #22  
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i still say leave it closed
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Old Aug 8, 2011 | 07:11 AM
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large increase in power w/ dump open = shitty exh system flow to begin with...

what liljay said^^^
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Old Aug 8, 2011 | 09:06 AM
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Originally Posted by Canbarelygo
i still say leave it closed


That cracks me up.
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Old Aug 8, 2011 | 07:29 PM
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Pics of your exhaust system and the cutout.
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Old Aug 8, 2011 | 10:05 PM
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Originally Posted by nicentech
How close is it to your o2is it tuned closed loop? Have you monitored stft with it opened compared to closed
The o2s are tuned out but there still in the slp y and the cut out is under the rear seat. I got the car out earlier to beat on it a little to see if I put tell any differance but the cut out got stuck open before I could really do any adjusting.
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Old Aug 8, 2011 | 10:07 PM
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Originally Posted by LilJayV10
What's the AFR and injector duty cycle? Maybe the injectors are on the border line and with the added air from the cutout open they are shutting down.


I would think a tuner would look at those two things pretty quick after a power loss that big.
Maybe so, the injectors are at 94%.
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Old Aug 8, 2011 | 10:08 PM
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Originally Posted by Canbarelygo
i still say leave it closed
Should listened, it got stuck open today. haha
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Old Aug 8, 2011 | 10:15 PM
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Why are the O2 sensors turn off?

Or do you mean the rears are deleted and the fronts are left?
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Old Aug 9, 2011 | 01:24 AM
  #30  
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nobody wants to listen lol

um in realty the 94% duty cycle is kind of excessive. i would suggest goin bigger and see what it does.

buuuuuuuuuuuuuuuuuuuuuuuutttttttttttttttttttttt

get loud exhaust and get it over with quit dickin with the ORY+cutout fad thats comin back. x pipe ftw.
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Old Aug 9, 2011 | 09:06 AM
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Originally Posted by LilJayV10
Why are the O2 sensors turn off?

Or do you mean the rears are deleted and the fronts are left?
The rears are deleted but still there, fronts are running.
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Old Aug 9, 2011 | 09:17 AM
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Originally Posted by Canbarelygo
nobody wants to listen lol

um in realty the 94% duty cycle is kind of excessive. i would suggest goin bigger and see what it does.

buuuuuuuuuuuuuuuuuuuuuuuutttttttttttttttttttttt

get loud exhaust and get it over with quit dickin with the ORY+cutout fad thats comin back. x pipe ftw.
I would have already replaced the injectors but last time around they were at 89%. I am going to put bigger ones in it, just havn't had a chance to buy any yet.

The car had the full exhaust on it when I bought it. I was pretty much given the cutout so I was giving it a shot.
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Old Aug 9, 2011 | 08:41 PM
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What fuel pump are you running?
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Old Aug 9, 2011 | 09:48 PM
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Originally Posted by LilJayV10
What fuel pump are you running?
I'm still on the stock pump
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Old Aug 9, 2011 | 10:34 PM
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There's a good chance you need to upgrade your pump. The pump might not keep with the injectors which can make the injectors stay open longer.

If I'm wrong about this someone say so.
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Old Aug 10, 2011 | 12:32 AM
  #36  
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idk about the pump a buddy of mine has a h/c/i car that makes 454rwhp is on the stock pump but with bigger injectors. you may not NEED a new pump but for the price you might as well just to eliminate that as being an issue. if you want a pump your not gonna max out until you start makin big power thats still intank and basiclly a stock replacement get a deatschwerks pump they look like a warlboro but flow much more fuel and have a nice warranty and are pretty damn cheap
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Old Aug 14, 2011 | 03:47 PM
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Any update on this?
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Old Aug 14, 2011 | 04:10 PM
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That's awesome. I thought it was a typo at first and he meant 7.7 rwhp, but he really meant 77! Definitely something wrong and I'm curious as to what's up with it.
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Old Aug 14, 2011 | 04:44 PM
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I'm originally from AR, interested in hearing who tuned it..
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Old Aug 14, 2011 | 07:55 PM
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We tuned it. It was not a fueling issue that caused the loss. The injectors did reach 94% with the cutout closed. But was lower with the cuout open. We did discuss him needing larger injectors.

Once the tune was adjusted for the cut-out open it still net him a loss of around 38hp. The car went way rich when the cutout was opened (not lean as one would guess).

We have seen gains of varying levels wioth cutouts but this is the first time we have seen one lose. My thoughts are that his cam/heads combo needs the backpressure.
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