It was 105*F outside today...

At speed (greater than 60mph), I could maintain 220 with the AC on. But it would never come down below 220.

At any speed less 60mph on cruise control, the temp would start creeping to 235, at which point I kick the AC off. It takes about 5 minutes to come back down to 220.

Both fans were on all the time because the temp was high enough to keep them on, they never cycled. (normally on say an 80*F day, neither fan comes on at all and the temp stays right at 195).

stock thermostat (195), stock radiator, i have an air dam, no leaves or junk stuck in there, etc.

Time for a new radiator?

Can anyone else share what temps they run at under similiar circumstances (AC on, 105+ outside, 5.7 350?)





With the AC on and in "slow and slower" traffic (40mph-20mph-40mph type stuff), temp would creap up to 235 before I turned the AC off. Temp would hang at 230-235 until I could get above 60mph, where it would slowly creap down to 220.

 

have you considered swapping in a 180 stat? should help keep the highway temps down some alittle more and give you more lee way when is traffic for the temp to go up some more before hitting the 230's

also what kinda coolant mixture are you running? with decent airflow it should of been keeping alittle cooler.

 

In the heat this week, mine's running at about 190 in traffic and doesn't get much better on the freeway. This is with the stock radiator, a stewart stage 1 pump, 160 degree stat and two 14" Perma-Cool fans running all the time. Not ideal, but not bad in this heat (over 100). This is with a 350 (no a/c) and uncoated SLP headers that throw out a lot of heat. I would expect yours to run a little warm in this heat, especially with the air on. I wouldn't get too worried until I saw over 240. I've seen thirdgens run up as high as 255 without trouble (but I wouldn't run it there for long).

Planning on doing the aluminum 2 row 31"x19" radiator later this summer .
-Rich-

 

My car a 88 lo3 with the air on and 90*F outside the car will run at the line in between 100-220 wether i'm cruising on the bypass or sitting in traffic. the only mods done to the car is new fan motor (single fan) and a new rad.(cracked plastic housing) and a 180 stat.


also check to see how long it takes your fan to get up to full speed.

that was the biggest problem i had was the fan would not achaive full speed.


also is the air dam on the car?

anybody need a good third gen radaitor core i have one you can have it just needs a end tank.

 

i would get one of thoes cheap reverse flush kits they sell that uses a garden hose to flush out the cooling system.

get some of that coolent cleaner additive, add it, run the system with the heater on ( like the directions say) then after its done, drain the system, then reverse flush it..

that should get the crud out of the system.

then refill with a mix of coolent and water... and perhaps some water wetter if you wanna spluge

 

I was in that same heat ( over 100*) here in California this past week and my LO3 with a Stewart Stage 1 waterpump, 195* thermostat, stock radiator, two 12" Perma Cool fans and AC running in stop and go freeway traffic (10 to 20 mph) , the engine temps reached the mark past the 220* mark on the factory temp gauge not really sure what the actual temp is but, the AC was blowing reasonably cool air (I wasn't about to shut it off) and actually last year when I was using a 180* thermostat, the engine temps in these same conditions reached the beginning of the redline on the gauge.

In cooler weather 85* or below, the engine temps rarely hit past the 220* mark even in stop and go driving and at freeway speeds the temps are well below the 220* mark.

My engines cooling system has been chemically backflushed with the Prestone kit (didn't really have to but, for peace of mind) and running 1 gallon of antifreeze. I was running straight water with Redline Water Wetter but, didn't really notice any significant improvement.

 

well, the 86 lb9 with single stock fan will maintain 195' with a 180' stat, on a 90 degree day in trafic, it wont go past 220, with no traffic, still 195. the thing is, the fan comes on at 195 and stays on, except for high way speeds. hmmm??

 

my 88' 350 tpi in 98* weather stays with the a/c on, on the freeway, at 185* (60 + mph). in the city the temp goes up to 216* around town idling, with the a/c on. this is with.... a new radiator, waterpump, hoses, thermostat and cap.

 

Hey 91. Where in CA are you? I have a new aluminium radiator and a 180 stat. Last week the coolest day was 102. Driving around town with the ac on max and the fan all the way up, the temp was right around 210.

Brian

 

My temp usaully runs around 180* with my ac on in 100* weather I am running about 225* I thought that was quite the excessive change. Last year I rebuilt my entire cooling system. New radiator, water pump, 170* thermo, JET lower temp fan switch, and new relays.