don't you mean that a PCV system is good vs an EGR system ?
a pcv system takes the blowby from the sump. an egr takes exhaust gas and
recirculates that.
however I think that an EGR system is a good thing anyway, if it is properly
working on modern cars, however in the 60's and 70's it's bolt on presence
along with leaner mixtures just served to raise the overall operating
temperature of the engine, I don't have an egr system on my 77 mgb, (weber).
gulp valves and air pumps and zeniths , and cat. converters are another
story entirely.
ted stowe
-----Original Message-----
From: xyzabcde@earthlink.net <xyzabcde@earthlink.net>
To: Bill Saidel <saidel@crab.rutgers.edu>
Cc: mgs@autox.team.net <mgs@autox.team.net>
Date: Saturday, November 28, 1998 12:53 PM
Subject: Re: some car mechanic help
>Bill Saidel asked:
>
>> What is a Gulp Valve and what does it do?
>
>This is a piece of "emissions crap" that keeps the air pump from messing up
your
>carburetion. The air pump injects fresh air behind the exhaust valve
causing
>the unburned gases to burn some more. The gulp valve keeps the injected
air
>from going into the intake. As long as this system is in working order, it
>doesn't hurt the car and it helps the environment.
>
>> What is an E.G.R. valve and what does it do?
>
>This is "emissions crap" that's actually good for your car. Wherever
possible I
>retrofit this to earlier cars, like my 1100's. The EGR valve vents the
blowby
>pressure in the sump into the intake where it is reburned and also lubes
your
>rings making them last longer.
>
>> Same for Anti-run-on valve?
>
>Various modifations designed to make a B run cleaner also make it run on
>(diesel), for instance, the 190 degree thermostat which makes the car burn
fuel
>more efficiently, but also necessitates thermostatically controlled cooling
>fans. This valve shuts the car off after the engine is stopped.
>
>> How important is the Fuel cut-off valve and what does it do...does it
>> do what its name says in case of an accident? If it is not there, does
>> that mean it is not strictly necessary to run?
>
>The fuel cut-off valve was required by the US gov't to stop gas from being
>pumped after a car has been rolled. Real cars have a ball valve, like on a
>snorkel, near the fuel tank. If the car overturns, the change in direction
of
>gravity causes the ball to move into a position to cut off the fuel from
the
>tank. In a B, the valve somehow senses sudden changes of direction and
shuts
>off the power to the fuel pump until the switch is reset. This means that
a
>fender bender will make your car stop running and if you don't know about
this
>gadget, it won't run until you have it towed somewhere where people do.
The
>valve is next to the master cylinders and looks a lot like a high beam
switch on
>an early car. The reset it, push down on the top and it will click.
You're car
>will run fine without it but there's no reason to remove it if you can
remember
>it's there and how to reset it when you're flustered and upset about an
>accident.
>
>> One last question: someone local suggested that I remove all
>> the "emissions crap". What are the mechanical consequences (let alone
>> legal) of doing that? And what parts under the hood represent the
>> "emissions crap"
>
>The "emissions crap" components that make a B run badly are the ZS
carburettor,
>the EGR valve and the catalyst.
>
>EGR valves make all cars run badly and I don't think they clean up the air
>enough to justify making the car work that much harder. To disable it,
remove
>it and replace the washer-like restrictor under it with a dime, then
reinstall
>and put a BB in the small vacuum line to it. The smog sniffer won't be
able to
>tell.
>
>I was told that the SU's were replaced with the single ZS carb because it
was
>easier to install an automatic choke on it. The govt required automatic
chokes
>because Americans couldn't be expected to remember to turn the choke off.
The
>water activated choke is one of the weakest points of the car and there are
>better carburettors with automatic chokes.
>
>The problem with the catalyst is the design. There are better modern
catalysts
>and better exhaust manifolds available. A catalyst exchanges some gases
for
>others. IMHO, we won't know which gases were worse until an entire
generation
>was exposed to catalyzed exhaust emissions. Is it possible this has
something
>to do with the dumbing down of America?
>
>Oh yeah, and then there's the timing and internal engine modifications...
Maybe
>next time.
>
>Thanks for giving me this opportunity to vent about smog equipment and
>government regulations. I need to go out and work on my car, but this felt
>good. :-)
>
>Denise Thorpe
>all with EGR valves and nothing but EGR valves
>
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