NetNews Usenet Archive 1992 #19/NN_1992_19.iso/spool/rec/autos/tech/11861

Internet Message Format | 1992-08-29 | 1.6 KB

Path: sparky!uunet!cs.utexas.edu!swrinde!sdd.hp.com!hpscdc!hplextra!hpl-opus!hpspdla!paulw
From: [e-mail] (Paul Welch)
Newsgroups: rec.autos.tech
Subject: Re: aftermarket cams and headers
Message-ID: <[e-mail]>
Date: 28 Aug 92 14:33:02 GMT
References: <[e-mail]>
Organization: HP Palo Alto Fabrication Center
Lines: 24

I re-built a Chevy 283 for my '63 Nova, and used a "mild street cam",
headers, etc., that were intended to improve performance.  Although I
live in California, I didn't ever have to smog this car since it was
so old.  However, I recently sold it, and the buyers condition was that
I have the car smog checked.  After adding an automatic choke and
a breather-type oil cap, I took it down to the local smog-check
facility.  The mechanic hooked everything up, started the test, then
promptly turned to me and gave me a dirty look, like my car just
ruined his smog-checker!  Actually, it just pegged the needles on his
gages.  Of course I assumed the worst (the car will have to be buried
in some land-fill facility that accepts hazardous waste), but after
playing around with the idle mixture and the timing, he was able to
get the car to pass.  Unfortunately, the performance dropped about
50%, but it did pass.

With a newer vehicle, things might be better (such as the cat.
converter, etc.).  I doubt that a simple change to headers would
affect the hydrocarbon output much, but they are one of the cheaper
ways to buy a little horsepower.  Without a test facility it may
be difficult to assess which modifications actually increase polutants.

Good luck-

PW