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Car slower after Header & ORY install...Why??

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Old Mar 25, 2005 | 08:19 AM
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Default Car slower after Header & ORY install...Why??

Previously my car had stock 02 headers, stock y-pipe with cats and borla no plate. I just finished installing Mac Mids, ORY, NGK plugs and Magnaflow cat back. My car is running fine however there's no way it's as fast as it was before . I figured I would at least see a 10hp gain not a loss..I'm thinking about taking this stuff off and going back with stock! I'm going today to have the air codes and rear o2 codes deleted and maybe this will make some sort of difference. Did anyone else experience this with a complete exahust install? Thanks,

Kevin
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Old Mar 25, 2005 | 08:21 AM
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WTF

I wonder if it lost low end TQ but gained higher end HP?
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Old Mar 25, 2005 | 08:28 AM
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That's what I thought at first, but it still doesn't pull as hard after 4k rpms..
I even used to have a traction problem in 1st & 2nd at 4k or 5k rpms, but not anymore....It just doesn't feel like it's all there
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Old Mar 25, 2005 | 08:39 AM
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Look into getting a tune.
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Old Mar 25, 2005 | 08:53 AM
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Old Mar 25, 2005 | 10:25 AM
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My felt the same exact way. You can get a tune, or get a Mass Air Flow Translator to adjust the A/F ratio for now. That's what I did. Just think of it as a band aid.
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Old Mar 25, 2005 | 01:37 PM
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I had the same feeling with my car; just put headers and ory on 2 weeks ago. I had a bud follow me in it and he said she was running rich enough to smell it. I just got my HPtuners today and will see how bad the a/f ratio is. I would suggest getting a tune of a MAF translator like the other guys said. I am going to see if I can get my car ironed out this weekend.
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Old Mar 25, 2005 | 02:12 PM
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find a local guy w/HPTuners for your year and scan the car, even if its narrowband. you can still get a pretty good idea if you're too far off.

if you do sell your magnaflow let me know
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Old Mar 25, 2005 | 06:30 PM
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Check for leaks, Damaged plug wires, inproperly gapped plugs
Did you have to extend the o2 harness? If so did you cut and splice or use extensions? how old are the o2's Either way check those connections. Reset the PCM if you've not done that already. Last but not least it might need a good tune, as the air and rear o2 codes probably won't have any effect
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Old Mar 26, 2005 | 12:23 AM
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something could of happen to the o2's but then again you should notice that. the back o2's since you are running an ory, will not throw a code for a couple of weeks unless already deleted. if the car runs normal but it is just slower then the problem may be the air/fuel. i just got finished installing macs on my car and had a computer tune and it runs really well. hope everything works out.
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Old Mar 26, 2005 | 12:56 AM
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u need to get it tuned and get the codes deleted and trust me the car will feel stronger once u do that
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Old Mar 26, 2005 | 01:22 AM
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I had the rear o2's & air codes deleted today. I went to Extreme Performance in OKC and they have HP tuners. They also scanned the pcm and deleted the left & right bank running rich codes from driving around with open headers....Seems to be running much better now..

Thanks for everyones help and input...

Kevin
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