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  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-

Pass Emissions With No Cats ?

  • Thread starter Thread starter Dave2000GT
  • Start date Start date Mar 30, 2014
D

Dave2000GT

Active Member
Oct 3, 2005
229
26
39
Seattle
Mar 30, 2014
#1
  • Mar 30, 2014
  • #1
Can I pass emissions with the following setup ?

GT40p heads
Explorer Intake
Stock HO Cam w Crane 1.7 Roller Rockers
FRPP headers
73mm MAF
Offroad H-Pipe
Flowmasters
 

Bullitt347

I have been doing it wrong this whole time
15 Year Member
Mar 23, 2007
3,951
2,906
194
Middle of Maine
Mar 30, 2014
#2
  • Mar 30, 2014
  • #2
In Oregon the answer is no. They do a visual inspection and when they stick the mirror under the car to look for the catalytic converters and see none, then they will fail you.
 

smkshw

5 Year Member
Feb 12, 2010
1,095
235
94
Mar 30, 2014
#3
  • Mar 30, 2014
  • #3
+1....negative....
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,296
1,640
214
Acworth, GA
Mar 30, 2014
#4
  • Mar 30, 2014
  • #4
It's a crapshoot. Some heavily modified cars pass the sniffer with no cats, and some stock Mustangs fail with cats.

Kurt
 
D

Dave2000GT

Active Member
Oct 3, 2005
229
26
39
Seattle
Mar 30, 2014
#5
  • Mar 30, 2014
  • #5
Ok I admit... This was a trick question.
Went through the sniffer this morning and passed no problem.
 

revhead347

Apparently my ex-husband made that mistake.
20+ Year Stangneter
Jun 14, 2004
9,296
1,640
214
Acworth, GA
Mar 30, 2014
#6
  • Mar 30, 2014
  • #6
How far off were your numbers. My Mustang aces emissions with cats. I haven't tried it without.

Kurt
 
D

Dave2000GT

Active Member
Oct 3, 2005
229
26
39
Seattle
Mar 30, 2014
#7
  • Mar 30, 2014
  • #7
revhead347 said:
How far off were your numbers. My Mustang aces emissions with cats. I haven't tried it without.

Kurt
Click to expand...
Actually I don't know - the guy at the test station said I passed easy but when I looked at the printout later on it didn't have numbers just a PASS, I think you might only get it on a fail to help diagnose. Probably depends on state also, they all have different limits in place. This reminds me I need to update my profile I'm in WA now not OR.
 

David Pepiton

Active Member
Dec 17, 2011
662
68
49
Laveen, Arizona
Mar 31, 2014
#8
  • Mar 31, 2014
  • #8
I passed with no cats though I have stock e7s egr and air pump.
 

tonydalrymple

Active Member
Nov 27, 2004
167
29
39
Salt Lake City, Utah
Mar 31, 2014
#9
  • Mar 31, 2014
  • #9
It really depends on the state you live in; sometimes there is a difference between one county too another. Just for comparison's sake..... Max HC idle in Utah (Davis county) is 220PPM; measured at idle & 2500rpm. In SoCal (San Bernardino County); Max HC is 85PPM at 15mph & 67 at 25mph. You'd think the California test is tougher, and you'd be right for anything above idle. But cams with big duration numbers & tight lobe separation typically clean up well off idle; at idle the HC's can be pretty bad.... I played heck trying to pass Utah emissions with my custom cammed 331 stroker. But that's a story for another day....
 
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