This is topic Question about cams and smog in forum Tech Talk at Northern California Ford Owners  .


To visit this topic, use this URL:
https://californiafords.com/cgi-bin/ultimatebb.cgi?ubb=get_topic;f=6;t=003917

---

Posted by RioredGT (Member # 2300) on :
 
Can cams keep you from passing smog? If so, why? I'm about to throw a set of ported and polished svo heads in my 98 gt and wanted to put cams in there at the same time to try and get the most gain, but wasn't sure if they'd keep from passing smog.
 

---

Posted by KCmustangboy (Member # 1927) on :
 
YES! cams will keep you from passing smog, you need to find someone who has a lot of cam know-how and ask how much of a cam you can run and still pass. They are a few smog guys on here I am sure they would be glad to tell you what the most you can do is. Although remember just because it "should" pass doesn't always mean it will. But than again that could work the other way in your benefit.
 

---

Posted by 66 AC COBRA (Member # 904) on :
 
when u smog it, make sure u have a stock h pipe on it with good cats, this is very important, if u are going long tubes, ur gonna have problems anyway
 

---

Posted by Black94 5.0 (Member # 655) on :
 
Basically~~Cams make horsepower by letting more air/fuel in the cylinders....More air/fuel in the cylinders means more air/fuel comes out...The smog machine picks up on the added exhaust gas and fails the smog....

I'm sure a set of 99 PI cams sould give some added power and are still emmision legal...If you put some aftermarket cams in your engine, just ask the manufacture if they are smog legal...
 

---

Posted by 66 AC COBRA (Member # 904) on :
 
some cams arent smog legal but will easily pass smog, like the b 303 or f 330 still weaknuts cams but they will pass and are considered "illegal"
 

---

Posted by Wolfie351 (Member # 651) on :
 
The problem with aftermarket cams is the overlap that may let unburned fuel go through the exhaust valves at idle. With the new treadmill testing, it's my understanding that there is no idle test which would greatly help people with stout cams. I pass just fine with a 351W and F cam.
 

---

Posted by RioredGT (Member # 2300) on :
 
Thanks for the input guys. I'll be checking with comp cams and SHM to see what they have to say about their cams.
 

---

Posted by Jimbo (Member # 1456) on :
 
Cam companies will hesitate to say their cams will pass unless they have gotten a CARB EO# for the particular part. Not too familiar with 4.6 cams out their but I'd check for some cams with a CARB EO# first and see if their are any you like. As it has already been mentioned, the new(to the bay area) dyno smog checks will probably favor cars with a bit of a rough idle, seeing as how there is no idle test.
 

---

Posted by mustanggt5091 (Member # 444) on :
 
Or a nice smog tech
 

---

Posted by SBSkid (Member # 2560) on :
 
I have a E303 will that not pass smog it should right.
 

---

Posted by 91PONY (Member # 206) on :
 

quote:

---

Originally posted by SBSkid:
I have a E303 will that not pass smog it should right.

---