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Fighting the Smog Nazis: Stoopid AIR pump T-fitting

  • Thread starter Thread starter Darkwriter77
  • Start date Start date Mar 13, 2009

Darkwriter77

Resident Ranting Negative Nancy
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Apache Junction, AZ
Mar 13, 2009
#1
  • Mar 13, 2009
  • #1
Went to get Frankenstang's Capri smogged today. Used the same damned X-pipe I've been using since 2005 on teh Notch and on her car, never been a problem before, numbers always come out good and nobody throws a fit. Numbers were good today, but some random douchebag on a power trip decided to fail it for visual inspection on the AIR system because the bottom connection that comes off that vacuum-controlled T-fitting/valve doesn't go to anything.

Here's the X-pipe I have been using:

MUSTANG-UPR Products.com

See? No fitting for a AIR tube on there. Doesn't need it. Car's always passed just fine and dandy without it. So the bypass valve/T-connection thingy where it splits the line coming off the smog pump and going either to the exhaust or to the crossover pipe on the back of the heads has never had anything on the exhaust end. Again, never been an issue ... UNTIL TODAY.

REEEEEEEALLY wanting to avoid having to go track down a stock H-pipe to swap on and off this car, or having to buy a hi-flow H-pipe with an AIR fitting on it just for smog purposes, because funds are tight. The Smog Nazi "Referee" was trying to suggest that I could go way the hell downtown and try to plea my case to for a waiver of some kind, but I'm sure I have a snowball's chance in hell of convincing them that ANYTHING OTHER THAN 100% STOCK is kosher, regardless of the fact that it dyno'ed smog numbers well within established limits.

Soooo ... to appease these buttholes that are failing it because there's an "open connection in the AIR system," can I just do away with that vacuum-controlled valve and run a hose straight from the smog pump to the check valve of the crossover pipe going to the back of the heads? Will this cause things to run lean, or affect the smog readings negatively?
 

jrichker

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  • Mar 13, 2009
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See the picture for the mods to your existing X pipe. Have a muffler shop fab up a cross pipe and T to connect the smog pump's AIR pipe. Some bending and fitting may be required, but I am sure you can handle it.

 

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Darkwriter77

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Mar 14, 2009
#3
  • Mar 14, 2009
  • #3
Can I not simply do without the AIR tube to the exhaust? It passes without it, as far as numbers go - can't I just delete the bypass valve going to the exhaust and just run a straight tube from the smog pump to the check valve of the crossover tube going to the heads?

Modifying the X-pipe *could* be done in theory, but there's GOT to be an easier way to it. (Gawd, I wish I had a welder ... AND wish I knew how to use one... )

Will running a straight hose from the smog pump to the crossover check valve cause it to run lean or anything like that?
 

jrichker

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The theory is that catalytic converters have to be up to a certain temperature range to work correctly. Too cold and the catalytic reaction doesn't happen. Too hot and the life of the catalyst is shortened. Or the catalytic honeycomb may break up and obstruct the exhaust, creating more heat. The cats are too cold to work properly when the engine first starts, so the computer directs air to the heads. This brings the temperature up to operating range very quickly.

Putting the air into the heads once the engine has warmed up will heat things up very high, and may possibly damage the cats. The exhaust headers and pipe to the cats will get very hot. That's one of the reasons the computer switches the air to the tube on the cat converters. It also lowers the heat in the engine compartment and reduces the possibility of heat damage to the wiring and other components. This also reduces the possibility of fire.

If you can find someone with a welder, Home Depot or Lowes can supply 1/2" or 3/4" electrical conduit to make the crossover. Fill the tubing with sand and heat it to bend it. That will enable you to make any pretzel shape that you want.
 

Darkwriter77

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Mar 14, 2009
#5
  • Mar 14, 2009
  • #5
Hmmmm ... so, the bypass valve is actuated according to engine temperature? Or is it RPM's? Either way, I guess that idea's out. Dammit ... nothing's ever easy with my cars.

Lynn knows someone that'll loan her a stock H-pipe, so I guess we'll have to go that route, as we're not gonna have time before tags are due to modify the current X-pipe. I think I'll just wind up selling the UPR X-pipe later and use the money to buy a stock H- or other midpipe with the AIR fitting already on it. Sucks that it's such a big deal this year and yet it never was in prior years. Guess I should've known better than to go through smog on Friday the 13th.

Thanks for the info!
 

Darkwriter77

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Apache Junction, AZ
Mar 14, 2009
#6
  • Mar 14, 2009
  • #6
Wound up drilling a hole and threading in a pipe fitting after the cats but ahead of the X-junction and then running some copper tubing from that up to the rubber hose part coming off the bypass valve. It's ugly and it won't make any difference in smog numbers, but as long as it pleases the Smog Nazis, then ... whatever.

I added JB Weld to the elbow connection to help seal things up and kept it secure. Haven't attached the tubing yet, but I have it all bent up into position and everything, so once the JB Weld crap cures, I can finish putting this ghetto-rigged turd together and get on with life.

View attachment 266314

View attachment 266315
 

KamiKaziDK

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Mesa, Az
Mar 14, 2009
#7
  • Mar 14, 2009
  • #7
ghettofabulous! Have her take it in next time, women get away with everything. Did you take it to the one off of Greenfield or the one out in AJ?
 

Darkwriter77

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Apache Junction, AZ
Mar 15, 2009
#8
  • Mar 15, 2009
  • #8
Greenfield. Lynn came along with me, although she didn't want to go at all (even though it's her car ).

There's a smog station in Apache Junction? The Greenfield one is the closest one that I know of to AJ, unless there's one toward Queen Creek or something that I don't know about...
 

KamiKaziDK

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Mesa, Az
Mar 15, 2009
#9
  • Mar 15, 2009
  • #9
I think they used to have one off of Main out towards ironwood somewhere...maybe I'm just being retarded though. It's still an incredibly stupid reason to fail you guys though, I don' think I've ever had the inspectors actually check crap under my hood, esp if I passed fine.
 

FrankenStang

Now, give me a damn CT!
15 Year Member
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Florence, Az
Mar 15, 2009
#10
  • Mar 15, 2009
  • #10
Yeah, there is one in A.J. It's new.

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