Dear Reader,
        I own a 1978 Oldsmobile Cutlass Supreme 2dr RWD.  When i bought it
the stock engine was already swapped.  I did a tune up on it (just plugs
wires and coil) and in the midst of trying to get the right parts for the
tune up i was able to identify the motor that is in there as a Chevy 350
small block from like a 1990-1993 chevy pickup (it has fuel injectives).  I
also replaced the radiator with a brand new radiator.  I had been driving the
car back and forth to work every other day approximately 30-35 miles one way.
The engine sounded fine and ran fine, matter of fact i was outrunning most of
the new stuff on the freeway.  One day i overheated about 5 mins from home so
i pulled over let it cool off and took it home.  Since then i replace the
thermostat and went about driving it for about 4 more days until it ran hot
again.  i was running with out a overflow tank so the hose that i had
blocking off the overflow passage had burst and i lost all my coolant out the
passage where the overflow tank was suppposed to go.  i bought an overflow
tank, replaced the radiator cap, and refilled the radiator again, and
replaced with yet another thermostat.  it ran hot again, but it takes it like
a good 5 or ten miles of strenuous driving b4 it runs hot but when it does
run hot all the coolant bubles into the overflow tank then out the overflow
tank along with steam.  I totally removed the thermostat while it was hot one
day and held it up to cool air with tounges and watched it close so i knew it
wasnt the thermostat.  i ran it without the thermostat at all for 5 to 10
miles and it overheated again.  i checked the oil, there is no sludge or
signes of moisture, the coolant looks fine but i loose almost all of it out
the overflow tank everytime i run hot, and there is no water coming from my
dual pipes.  This is soooo frustrating because i have put so much time and
money into the interior because i thought the motor was straight.  I love
this car, what could it be, how do i fix this???? im no novice mechanic but i
will get under that hood and go to work, somebody help please.  Please tell
me its not a head gasket!!!!!!!! whoever put that engine in did such a good
job converting it and getting her running right, can you help,  keep in mind
she still runs strong as a bull, she just overheats too quick.