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Re: Question

To: "MURPHY, BARNEY D" <BMURPHY@scana.com>
Subject: Re: Question
From: "John F Sandhoff" <sandhoff@csus.edu>
Date: Tue, 12 Dec 2000 13:50:40 -0800
Dean asks:
> I have a '69 2000 that I purchased a few weeks ago. The smog system has been
> removed and plugged. Judging from what I've been reading, when this system
> is removed, the needles in the carburetors (SUs) should be changed along
> with reconfiguring the distributor to 1967 specs(?) and retiming to 16
> degrees.

The smog needles for the air injection system are a tad richer, so in theory
you should go to a slightly leaner set. My guess is the N-17 is what you
want; I haven't tried it myself yet because my dealer wants way too much for
them...

You have to pull the needle out of the dome and look for a number stamped on
the shoulder. Don't bend or bruise the needle getting it out, and be sure you 
get
everything cleanly aligned when you put it back together!

I think you already know, but you CANNOT simply reset the timing to 16 degrees
unless you change the weights and cam plate to a '7.5' unit. Otherwise you run
way too much advance and run the risk of piston meltdown. To check, carefully
remove the breaker plate (don't drop any screws :-) ) and look for a stamped
number on the cam plate. 7.5 means pre-smog (15 degrees mechanical advance).
17 means smog; wants to be timed at 0 degrees - ugh. Any other number means
you've got the wrong distributor in there :-).

And the vacuum advance goes to the barb on the carb (top front for 2000,
bottom rear for 1600), NOT the intake manifold. The advance should be hooked
up, and hooked up right - I'm surprised how many people rip it out! (The smog
2000 uses a vacuum switch on the thermostat housing. Doesn't hurt to leave
it alone as long as it's hooked up right!) While I'm on the subject, the PCV 
(hose
from valve cover to carbs) should be connected too. It helps purge the 
crankcase,
reducing sludge and yucky buildup.

Legal note for CA: "It is illegal to tamper, alter or remove emissions control
equipment on a street-operated vehicle". The law exempts us from biannual
inspections, but legally we can't alter what's supposed to be there. Oh, and
there's a move underway to repeal SB42 :-(

Ummm, Tom, you gonna make up some more smog plugs anytime soon? :-)

-- John
     John F Sandhoff   sandhoff@csus.edu   Sacramento, CA

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