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would putting PI heads on my 98 make it lean out??

  • Thread starter Thread starter 98blackstallion
  • Start date Start date Jul 27, 2005

98blackstallion

Member
Mar 30, 2005
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mtn home arkansas
Jul 27, 2005
#1
  • Jul 27, 2005
  • #1
ok guys right now i have on my 98 GT...the PI intake, Mac O/r H pipe, flowmaster 1 chambers dumped. I am wondering if I swap on the PI heads if that will make my car run lean? or if I will be ok? Cause i am wanting to throw a set on due to my car still sucking ass power wise but if I have to get a tuner then I am gonna have to wait longer. If i was to have to get a tuner i would get the SCT x-cal 2. clear this up for me guys please.
 

jstreet0204

Active Member
Jun 26, 2003
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Winston Salem, NC
Jul 27, 2005
#2
  • Jul 27, 2005
  • #2
In theory, it shouldn't make it run lean. The OEM MAF is not calibrated to a certain engine configuration. The problem is that you are going to be uping the compression a good bit, so some timing may need to be pulled out, also if you are using the PI cams as well the profile is different and the injector timing may need to be adjusted to match that. I think most people just seem to make much more power after the swap if they get a tune, but you should be okay for a while without.
 

98blackstallion

Member
Mar 30, 2005
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mtn home arkansas
Jul 27, 2005
#3
  • Jul 27, 2005
  • #3
alright thanks man
 

billfisher

Active Member
Jul 17, 2005
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38
huntsville, AL
Jul 27, 2005
#4
  • Jul 27, 2005
  • #4
whoah there

I made just the intake change, and mine (96) leaned out dramatically. a tune was required. the motor lost power and started hard. (slowly)
 

CanadaStang

New Member
Sep 7, 2003
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Mb
Jul 27, 2005
#5
  • Jul 27, 2005
  • #5
98blackstallion said:
ok guys right now i have on my 98 GT...the PI intake, Mac O/r H pipe, flowmaster 1 chambers dumped. I am wondering if I swap on the PI heads if that will make my car run lean? or if I will be ok? Cause i am wanting to throw a set on due to my car still sucking ass power wise but if I have to get a tuner then I am gonna have to wait longer. If i was to have to get a tuner i would get the SCT x-cal 2. clear this up for me guys please.
Click to expand...
You should be fine, I ran mine for awhile with no tune. TweekedGT also ran his with no tune when he had about the same mods as you, and I don't believe he had any issues either. You may have lean spots, though, so it's a good idea to still get a tune when you get a chance.
 

tomustang

Psychotic Member
Founding Member
Jun 8, 2000
3,434
2
78
McLean Hospital
Jul 27, 2005
#6
  • Jul 27, 2005
  • #6
I never had a tune on my PI, ran like a Ox too.
 
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