31 Jul
2001
31 Jul
'01
4:37 a.m.
Chris Kennedy wrote:
- A cast iron head. I'm not sure who thought that
the combination of
a cast iron head and an aluminum block was a good idea, but
between the difference in thermal expansion rates and the tendency
for cylinders two and three to "sink", Vegas blew a lot of head
gaskets. Enough so that a special replacement gasket appeared on
the aftermarket that was thicker around numbers two and three.
The 80's Caddy 4.x liter engine used cast iron heads on an aluminum
block as well. It isn't known as a good engine either.
- The "vacuum leak center". The Vega
appeared at the beginning of
the 70's, a period wherein, rather than addressing the underlying
issue of meeting emissions by making engines run right, Detroit
applied a series of kludges, almost always in the form of assorted
and sundry vacuum delay valves and vacuum motors. The result was
a generation of induction systems that could do parlor tricks with
exhaust gas but didn't have a clue when it came to a cup of high-test,
and as implemented on the Vega came in the form of a collection of
valves and hoses that invariably leaked under transient and
difficult to reproduce conditions.
The 70's were the very beginning of smog equipment being mandatory on
cars. I think it is reasonable that the smog equipment didn't work the
best, was horrible to work on, and was a plumbers nightmare. It's
gotten a lot better, as they have gained experience with it.
Chad Fernandez
Michigan, USA