5.3 coolant temps
 

what is optimal for coolant temps?

im currently running around 185 while on the freeway at 70 mph then around 190-200 while in stop and go traffic

Re: 5.3 coolant temps
 

Thats shoukd be fine the ls tend to run around 210 stock. Mine runs around 200 all the time

Re: 5.3 coolant temps
 

"optimal" to the GM engineers is 195-215 in terms of efficiency as measured by fuel useage vs manifold pressure... i.e. thats when the engine will make the most power off the least fuel. This is why you'll see LS powered vehicles running 15-30* hotter than the old SBC stuff.

Its also why I yell at people who run 160* stats. Because the engine is meant to run warm, your actually sacrificing power, efficiency, and longevity by doing so.

Your temps sound fine. I've seen logs from AZ/TX/NM guys who have been 220-225* without the engine knocking or pulling timing. With a good cooling system,and no other mechanical or tune related factor, you can actually worry about other heat related concerns (trans) before you legit over heat these.

Re: 5.3 coolant temps
 

awesome thanks for the quick responses guys!

Re: 5.3 coolant temps
 

Agree with the rest....my fans switch on @205- off @ 195. Sounds like you are good on it ....longhorn

Re: 5.3 coolant temps
 

Mine runs 200 all the time, stop & go traffic in summer it can reach 210-215 but it cools down quick when the fans come on. And that is with a 195 thermostat.

Re: 5.3 coolant temps
 

Several stock tunes don't turn fans on until well into the 220's.
You're fine, don't sweat it...harharhar...