Re: 4.0 failed emission test in VA, what to do?
1200, 1500, 2500 etc - NOx probably forms at all of those
temps, just at 2500 it becomes significant enough for the
greenies to get upset. At about 3000 it goes wild.
It's the peak combustion temp that counts the most.
Exhaust temps are considerably lower, partly because lots of
the heat energy was converted to mechanical energy after the
peak temp was reached,- hopefully anyway.
And all the metal surrounding it heat sinks the heat away.
Interesting - peak temps are way higher than the melting point
of aluminum pistons, but they survive.
Yes, some cams are built to "leave" a little exhaust in the
chamber, eliminating the need for external EGR systems.
(I don't like those though, you can't disconnect them!)
And they do it all the time, rather than only when it's
Notice an external EGR valve drops out, stops working, under
full acceleration, a cam can't.
Know what the biggest polluter of NOx is?
Not industry, not cars, not even barbeques or lawn mowers.
Taco Bell gas is different.
Seaweed! Man made NOx is less than 1% of the total.
So if you want to help the environment, burn some seaweed.
Oops, no don't burn it, it'll produce CO and CO2.
Don't just pile it up to rot anyplace, the rotting seaweed
will produce methane gas - Hydrocarbons.
Don't carry it anywhere to store it, you may breathe harder
from the extra work and produce more CO2 when you exhale.
I guess the best you can do with it is eat it - no wait,
it'll end up in the sewage system and ground water supply.
Don't bury it, it'll hurt the ground water too.
I guess the only safe way is to shove it up a greenies ---.
Changing the base timing on a computer system often wreaks
First it changes the burning slightly, then the O2 sensor
detects the Oxygen isn't "normal," then the computer "thinks"
the mixture's wrong, so it adds or subtracts fuel.
Now you have 2 problems, timing's slightly off (no big deal in
in itself) AND fuel mixture is no longer right.
Most times when they say 14, they mean 14, not 13, not 15.
It's surprising how just one degree of base timing error can
introduce a world of drivability problems.
You have to follow the label instructions to the letter - if
they say open the trunk lid - do it - there's a reason.