Tim, et al,
With all due respect, I have to take issue with your comments regarding the
air pump. Having restored a '76 TR6 to as close to original as possible, I
can confidently say that the air pump did not introduce fresh air into the
cylinder. Rather, it introduced fresh air into the exhaust manifold to
allow full burning of any fuel vapor or hydrocarbons escaping the cylinder.
This is why the exhaust manifold temperatures of an engine with an air pump
is much higher than those cars without the air pump.
I have disabled my air pump by removing the belt and adding a new (fresh)
check valve to keep the exhaust fumes from heading back toward the emission
control equipment. The TR6 runs better, and a little leaner (better gas
mileage) with the air pump disabled. Also, to address a comment by Hugh
Fader, the fan belt running the air pump is a very short belt. The beauty
is that it only runs the air pump, so removing it doesn't affect any other
engine components.
I will entertain comments counter to my feelings.
Eric
'76 TR6 (CF52678U)
[tim hutchisen wrote:]
The air pump will _not_rob valuable horsepower a whole lot. It's job is
to provide fresh air into the cylinder to help the burn of hydrocarbons and
carbon monoxides. It helps in the efficiency of the flame front inside the
cylinder. (Read: better fuel economy). It also reduces the temperature
inside the cylinder. So...
remove the air injection system if you want to:
1.) pollute the atmosphere more 2.) get worse fuel economy 3.) shorten the
life of your engine and 4.) create _more_drivability problems due to rich
A/F mixture.
<<snip>>
Removing emissions systems usually result in an increase of drivability
problems and decreased fuel economy as a whole. It is a false perception
that these systems rob horsepower. It was the lower compression ratios that
robbed the horsepower through the 70's, not the emission systems. Lower
compression ratios were the easiest way to meet the strict emission mandates
set in the decade of disco. The engineering had not caught up with the
mandates at the time in regards to cleaner running engines.
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