Overheating 440 69 Roadrunner

Jim occhiuto

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I think I've posted before on my overheating woes so wanted to give an update.

So previously had overheating on my 440 . It has a pretty decent (street drivable) cam, headers, wieand intake, electronic ignition 16 degrees idle 36 at 2500 rpm.

Cronic overheat but not idling..only above driving. Even took auto Trans out of radiator and put on a standalone cooler not near radiator. I had an aluminum 22" radiator, no shroud, clutch fan.

Up at 230 degrees in 10 minutes driving. Cools down when I stop and idle.

So here's what I did..
1. Replaced radiator with a used factory 22". This allowed me to mount shroud.
2. Replaced water pump with a FloKooler high volume pump.
3. Changed from clutch fan (would pull about 300 cfm at idle in front of radiator) to a non clutch fan, spaced about 1" from rad. Retested air flow..got about 900 cfm in front of rad...nice boost.
4. Put 160 thermostat in.

Results...still overheats..now worse. Good at idle No good high speed.

Measured top hose temp..about 190 bottom hose now 185..rad doesn't seem to do much.

Im at a loss...try a new radiator...? Even tested for CO in Cooling system to see if cracked block, head gasket...2 different test kits..same results..fine.

Go figure..some crazy block obstructions? I ran water thru block and heads when I pulled water pump..all flowed fine.


One note..if I run 50/50 coolant and drive around to temp starts going above 200, I look at coolant and its brown...that's just 1 trip.

Any help appreciated.
 

V.R.D

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if you want to end this problem get a griffin rad you have the best water pump now do the rad. my 451 stroker runs 170 down the road and that is with a/c and my trans goes thru the rad and you need a 180 thermostat at a stop light 195 after our 4 min stop lights hear in Florida.
 
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