LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

open headers for dyno run??

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Old Jun 2, 2006 | 08:04 PM
  #1  
firebirdStud's Avatar
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Exclamation open headers for dyno run??

Alright, I was figurin I would get better dyno results with open headers... was I wrong? I figured I would run that way becuase I will have cutouts installed in the near future, but time ran short. I was doing good to get the damn thing burnin gas by now and broke in! So, is there any disadvantages to running open headers? I only live 6 miles away, so im gonna pull off the y pipe tonight at my house. Let me know asap! (Plus its gonna sound sweet driving there! )
Old Jun 2, 2006 | 08:45 PM
  #2  
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Re: open headers for dyno run??

If the o2 sensors are close to the collectors, do NOT do this. Fresh air circulates into the collector giving the o2's a false lean signal. The computer adds fuel, more fuel, and more fuel. This fuel is also added at full throttle unless you have a BLM locker installed. By the time you get to the dyno, it'll run like total @ss.

Mike
Old Jun 2, 2006 | 09:02 PM
  #3  
firebirdStud's Avatar
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Re: open headers for dyno run??

****. so should I just run the y pipe and disconnect the catback?
Old Jun 2, 2006 | 09:11 PM
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Re: open headers for dyno run??

If you have headers you can run open headers and nothing will get sucked in there. I have headers with x-pipe and I wouldn't recommend open header dyno runs because the exhaust will give you the back pressure the LT1 needs. Backpressure improves low rpm's and power but you can have too much or too little. Personally my car is faster with the x-pipe or exhaust on rather than open headers.
Old Jun 2, 2006 | 09:24 PM
  #5  
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Re: open headers for dyno run??

Originally Posted by firebirdStud
****. so should I just run the y pipe and disconnect the catback?
Yes, disconnect the cat-back and you'll be fine.
Old Jun 2, 2006 | 11:58 PM
  #6  
firebirdStud's Avatar
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Re: open headers for dyno run??

ok, I disconnected the catback, left the 3 inch y pipe on. Holly vagina that sounds soo sexy. Now I will have to get a damn electric cutout.
Old Jun 3, 2006 | 12:15 AM
  #7  
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Re: open headers for dyno run??

Firebirdstud; Hows it going man? Proud you finally got your engine together man. PM me with results if you don't mind. Later, bro.
Old Jun 3, 2006 | 02:44 AM
  #8  
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Re: open headers for dyno run??

AT WOT O2 Sensors arn't being used, right? So it wouldn't matter.
Old Jun 3, 2006 | 09:25 AM
  #9  
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Re: open headers for dyno run??

It applies the part throttle BLM correction to full throttle also, as long as it's adding fuel not subtracting. That's why they came out with the BLM locker - so part throttle corrections don't interfere with the full throttle tune.
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