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Auto owners with downpipe + cat back

Old Jun 24, 2006 | 08:53 PM
  #1  
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Auto owners with downpipe + cat back

Do you experience any problems with boost cut off in the higher rpms? I'm planning on swapping out these 2 items and have been told getting a cat back on top of the dp would cause problems.
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Old Jun 24, 2006 | 09:44 PM
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be careful because when i did that to my automatic I started running rich and would get fuel cut off, which sounds terrible.
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Old Jun 24, 2006 | 10:11 PM
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From: Oregon
PCS auto transmission controller

http://www.powertraincontrolsolution...content-4.html

Anyone use this?
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Old Jun 24, 2006 | 10:17 PM
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It seems like since and automatic is a 4-speed it will effectively 'lug' the engine a little more under full throttle and may be more suceptable to overboost.
? ?
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Old Jun 24, 2006 | 10:25 PM
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Originally Posted by arctic_silver
dont see a price, if its pricy u might just wanna get the power fc which works, and, or find someone who knows how to port the wastegates so u have les chance of fuel cut.
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Old Jun 24, 2006 | 11:19 PM
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Originally Posted by arctic_silver
Do you experience any problems with boost cut off in the higher rpms? I'm planning on swapping out these 2 items and have been told getting a cat back on top of the dp would cause problems.
When someone tells you it will cause problems, you need to ask them to be specific about what problems they are talking about.

If you add a DP or make the exhaust flow more freely in any way, the reduced exhaust backpressure will translate to higher boost pressure. The stock ECM fuel map runs out at something like 12 psi. Read - KABOOM. The engine will run right up there too. (Voice of experience).

You can reduce the boost with a controller or go the afermarket ECM route to make sure you don't lean out the engine.

I believe you said your car is an auto. The Power FC will work, BUT you loose the transmission hold feature. You can get around this by using a Purple Engine eater fuel controller. Expect a tuning requirement either way if you want to boost above stock levels.
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Old Jun 25, 2006 | 12:58 AM
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From: california
I've had no problems! check out my mods . all I had to do is change the wastegate pill to keep the boost at 10 psi. the best mod for our autos is the 4.33 gears
Jeff
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Old Jun 25, 2006 | 02:53 AM
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yea the only thing you need with those mods is a boost controller. If you have the stock intake then, you might be fine without it...but at the most all you would need is a boost controller.
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Old Jun 25, 2006 | 07:34 AM
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With a catback, dp, and modified airbox my automatic was hitting fuel cut after flat zinging to 12+ psi, and eventually the engine blew the seals on the front rotor.
Best bet is to get a boost controller of some sort. Either a piggyback ECU like the PFS 'Purple' box (there are several for sale) or one of the many manual or electronic boost controllers. The PFS ECU lets you retain the 'hold' feature of the transmission.
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