average running temperature on '74 911 (2.7)

vgarza · 02-13-2002, 12:46 PM

Hi - First post on this board.... so be nice !
I'm wondering what is the average temperature
that my '74 911 should be running at with an
oil cooler installed. I seem to be running
pretty close to 200 or so (probably 210 or
so in the summer). Is this about right ?

Thanks - Val

GeorgeM · GeorgeM's Garage

My '74 used to run around 200 with a loop cooler. Do you have a loop or radiator type cooler? Fan or not?

vgarza · 02-13-2002, 01:19 PM

Loop cooler I believe... I was thinking it should be running at around 180 or so - is that
not correct ? I've been told that the only things
that could make it run hotter is oil level, or the timing. It does have the large fan.

Jamul74 · 02-13-2002, 01:24 PM

My 74 without an oil cooler stays between the 180-220 range depending on outside air temp

vgarza · 02-13-2002, 01:29 PM

OK - so where is the "danger" zone on these cars?
Anything over 240 ? Or just the "redline" ?
Sounds like I'm OK and might be over-reacting
a bit...

I need to get the A/C working - so I was
just thinking that would make it run even hotter.

GeorgeM · GeorgeM's Garage

I think Bruce Anderson says 250 is way too hot, 230-240 is too hot, 220-230 is warmish, and anything below that is fine. I don't have access to the book or tech article or wherever I heard that, so those numbers might be off a bit.

My '74 used to see 240+ on really hot summer days and it scared the crap out of me, so I put on the loop cooler (it's what the plumbing and thermostat came with). It helped by 20-30 degrees on a good day as long as the car was moving. I would have put a Carrera or Mocal type cooler, but I sold the car.

I'd see around 230-240 in my '89 3.2 on the track in the heat of summer, so I put a Mocal in the front valence in series with the fender cooler. Now my temps don't go above 200 even on the track.