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gt40 or gt40 P - Which are better if want to keep smog?

  • Thread starter Thread starter Triple White 91
  • Start date Start date Jun 7, 2007

Triple White 91

New Member
May 24, 2007
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Jun 7, 2007
#1
  • Jun 7, 2007
  • #1
Just wondering which are better (gt40 iron or gt40P iron) in the area of keeping the engine smog legal, or are they both smog ilegal? I'm learning as I go so I hope this is not a stupid question. I have read that the P's flow better than the origional cobra gt40's, can be found on 97 to 01 explorer's and require special headers.
I
 

88mouse

New Member
Apr 18, 2007
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Mooresville nc
Jun 7, 2007
#2
  • Jun 7, 2007
  • #2
Both are smog heads. I would go with the p's.
 

JBeezy53

Member
Dec 28, 2003
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Sacramento, Ca
www.cardomain.com
Jun 7, 2007
#3
  • Jun 7, 2007
  • #3
88mouse said:
Both are smog heads. I would go with the p's.
Click to expand...

That is true however if you are in California the GT40P will not pass the visual because they do not have the holes for the EGR tubes in the rear of the heads. You could have them drilled for them or rig something up so they look like they are there.
 

88mouse

New Member
Apr 18, 2007
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Mooresville nc
Jun 7, 2007
#4
  • Jun 7, 2007
  • #4
just bolt the tube to the back. We have the same inspection here to. Iam an inspector if they know to look for that iam sure that they can tell that they are another set of factory heads
 

Triple White 91

New Member
May 24, 2007
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Jun 7, 2007
#5
  • Jun 7, 2007
  • #5
Both are smog heads. I would go with the p's.
Click to expand...


I'm a little confused. Do you mean they will hook up to the smog/egr stuff or they will not. Sorry if this is a dumb question.
 

Mustang78

New Member
Feb 8, 2006
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Aberdeen, WA
Jun 8, 2007
#6
  • Jun 8, 2007
  • #6
i know GT40's are smog legal, the P's are too they just dont hook up the same way your mustang does

~Mark~
 

RYC CUKR

Founding Member
May 19, 2002
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Orlando
Jun 8, 2007
#7
  • Jun 8, 2007
  • #7
You can bolt all your smog equipment up to the Ps. The only difference in the Ps and the regular 40s is that the Ps do not have the thermactor port drilled out on the back of the heads. That said the crossover tube will bolt up just like normal and look fine but it will not be functional.
 

JBeezy53

Member
Dec 28, 2003
559
1
19
42
Sacramento, Ca
www.cardomain.com
Jun 8, 2007
#8
  • Jun 8, 2007
  • #8
88mouse said:
just bolt the tube to the back. We have the same inspection here to. Iam an inspector if they know to look for that iam sure that they can tell that they are another set of factory heads
Click to expand...

Thats good to know, maybe I'll get some for my commuter.
 

68keyblr

20+ Year Stangneter
Mar 17, 2003
946
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49
Arizona
www.cardomain.com
Sep 5, 2007
#9
  • Sep 5, 2007
  • #9
I know this is an old thread, but can someone tell me if the GT-40 heads have the smog tube holes drilled?
 
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