Engine running hot in traffic

[carnutjw]

My 2 cents = 200 degrees F is OK, boiling point of 50/50 coolant mix is 223 degrees F. With a 15 psi radiator cap its 257 degrees F. If its not boiling over, you're fine. Most late model EFI setups run 190-210 if my memory serves me. Emissions are better/lower at higher temps and 200+ degrees removes any condensation/moisture from oil-pvc system??

 

[carnutjw]

PCV system.

 

[Cary Scott]

Absolutely correct on emission temps. I'll speak for GM as that's where I work, 210 is optimal operating temp for emissions and that's where our stuff runs. As you're running an EFI setup, I'd bet a dollar to a donut that that's what your system is programmed for.

 

[Cary Scott]

Keep in mind that, in order to be CARB and 50 state compliant, this is the new norm. I'm still stuck in the past where 180 was the magic number. My carbd car runs and is tuned for that and I don't live in an emissions state.

 

[Cary Scott]

Hey, almost forgot. Yesterday's fuel contained lead, which was a friction modifier and had a marginal effect on reducing combustion chamber temps. Today's ethanol blended fuels do reduce combustion chamber temps. 210 is the new 180.

 

[foxtrot]

My recipe for cooling old school GM small block engines:
-Fresh ethylene glycol in a 50/50 mixture
-HD water pump (closed impeller)
-four core aluminum radiator
-180 degree thermostat
-HD mechanical fan
-Stock pullys

 

[olds307 and 403]

My recipe for cooling old school GM small block engines:
-Fresh ethylene glycol in a 50/50 mixture
-HD water pump (closed impeller)
-four core aluminum radiator
-180 degree thermostat
-HD mechanical fan
-Stock pullys

I like the 2 core aluminum with 1" tubes over the 4 core but both seem to work well. I agree Frank, if it can cool a 403, it will cool nearly anything.

 

[Clone TIE Pilot]

Besides reducing emissions, hotter operating temperature also extends engine life. Back in the 60s, Ford found that 195 degree t-stats increased engine life by at least 30%.

Something to keep in mind, is that all IC engines run far below the optimum temperature for combustion. Running a engine colder than it needs to be is throwing power out the radiator instead of pushing the car.

 

[565bbchevy]

For the Intrepid fans I first ran a pair of 40 amp relays that lasted a couple years before one of them melted which caused the fan to stay on even with the switch off so I decided they must be running close to max amperage for the relays so I replaced them about 12+ years ago with a pair of 70 amp relays that use the larger spade terminals and haven't had a problem ever since.

 

[pontiacgp]

That is a good suggestion to use 70 am relays. if you want to do a neat job with the 70 amp relays this socket will do the job...

https://www.amazon.ca/dp/B000VUEDRU/?tag=rippca-20