What Coolant Temp ,is Correct?

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
I moved to Arizona about a year ago. I have a 383 stroker and it was running warm (200+ degrees) even on the highway (temps that day were about 112 degrees). The temperature sending unit is in the intake manifold by the thermostat.

I just installed a 3 core aluminum radiator and took the car for a short drive for about 10 miles (it is only about 95 degrees today) and the temp remained at 170 while on the freeway.

Is 170 degrees from the intake about 190 at the cylinder heads?

Is this too cool?

https://www.motortrend.com/how-to/how-to-choose-a-thermostat-for-your-classic-car/


most older car/trucks with carburetors and limited emission equipment will run fine ,
with coolant temps in the 170F-180F range ,
your correct if the engines running at 170F
the existing t-stats obviously opening at 170F
because the engine will continue to build heat up until the t-stat,
opens and allows coolant to absorb and transfer heat to the outside air flow
coolant temps should reach and remain at least at,
or only slightly higher than the thermostat rated opening temp.
if 170F is a bit cooler than what you want try a 185F 0r 190F thermostat.
some more modern fuel injected engines run better and were designed,
to have coolant temps maintained in the 200F-205F range.
in the ideal engine/cooling combo the thermostat opens at the set temp, and the coolant will be cooled as it flows through the radiator , at a rate thats fast enough,
that the coolant fluid exiting the engine will rarely exceed the thermostat.s rated opening temp
by more than about 10F degrees, having a radiator and fan combo that maintains a consistent coolant temp under all conditions makes tunning far easier and reduces engine wear and heat cycle stress.
consistent and dependable coolant temp swings, that are maintained under about 195F
vastly reduces the potential for detonation related engine damage

img212.gif

radcool1.jpg


most cars run considerably cooler coolant temps at freeway speeds due to the increased airflow and less need for the fan to provide that airflow, the true test would be to see what temp the coolant maintains after a 10-15 minute drive and letting it idle for 15 minutes with the air conditioning running like you might be forced to do in bumper to bumper traffic,
I doubt you'll have any issues if the temps stay under 185F or so under that set of conditions.
and Id bet most people,
would be thrilled to have a 383 SBC engine that consistently ran a bit cooler than average

what make model and year car/truck,

what radiator vendor, radiator brand and model number radiator was that?

I'm sure some member with overheat issues is sure to want to know,
any pictures or more detailed info posted would be nice,
BTW if anyone has engine overheating issues, adding an auxiliary,
additional high-quality oil cooler and or transmission fluid cooler,
with its own electric fan of the proper size,
does a great deal to remove heat loads that the radiator is currently forced to deal, with, and the added coolers,
can make a very noticeable reduction in engine coolant operating temps.
most high performance or towing applications benefit
from an added electrically fan cooled, transmission cooler and/or an oil cooler
dualcool.jpg



related threads
http://garage.grumpysperformance.com/index.php?threads/thoughts-on-cooling.149/


http://garage.grumpysperformance.com/index.php?threads/how-the-cooling-system-works-basics.853/

http://garage.grumpysperformance.com/index.php?threads/do-i-need-the-fan-shroud.13847/

http://garage.grumpysperformance.com/index.php?threads/tips-on-cooling.199/

http://garage.grumpysperformance.com/index.php?threads/correct-thermostat.5607/#post-26544

http://garage.grumpysperformance.co...ing-system-flow-rates-and-heat-transfer.9880/

http://garage.grumpysperformance.com/index.php?threads/copper-brass-vs-aluminum-in-radiators.4230/

http://garage.grumpysperformance.co...g-on-fans-alternators-and-oil-all-here.12628/

http://garage.grumpysperformance.co...oosing-an-engine-oil-cooler.15375/#post-90261

http://garage.grumpysperformance.co...fo-and-derale-trans-cool-pans.662/#post-34937
 
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