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I got my wifes Capri running last week, it runs awesome, we kept the mods to a minimum, better than stock cam, and a .040 overbore. IT overheats though, I put in a 160 degree thermostat(fail-safe), a new water pump, radiator cap, rodded out the radiator, new flex fan and shroud, it has an overflow tank, and I even put in some super coolant which was supposed to reduce the temp by up to 20 degrees. I have an aftermarket mechanical gauge. Cruising around is fine, but the moment the car stops, the needle starts climbing. It got to 240 the other day by the time I managed to find a place to park and let it cool off. The radiator is a 2 row, which is what originally came with the 302(this car was a 4-to-8 cylinder conversion.) I have the timing set correctly, what else could cause it to overheat so badly?
 

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I would upgrade to a 3-row radiator to start and make sure all your hoses are in good condition. If that doesn't work, then I would suspect head gasket installed backwards.
 

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Put a 180 stat in it and if you are going to replace the radiator go with a 4 core. The smaller stat could cause one to over heat. The 160 may work with a 4 core but not as well with 2 core.
 

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Agree, go to a 3 or maybe even a 4 row rad. When you bore a block it's ability to cool is lessened.
 

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Radiator is undersized. Spring for the four row and you'll be able to quit worrying about it. My car used to get hot just like yours with a bit of idling or even on the highway if the temperature got into the mid 90's. I put in a 4 row and a fan shroud and have never had a problem since, even idling in 100 degree weather.

Good Luck!

Phil
 

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My 85 5.0 use to overheat, spend money on rodding the old radiator and a bunch of other stuff. Finally I installed a new 4 core radiator and it never over heated again. Even stop and go traffic in Texas summers with the AC on. Hope this helps
 
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You're probably going to need to replace that fail-safe thermostat now, as well. My experience with those is that once the car overheats even a single time, the thermostat is forever stuck open. Just like having no thermostat, this will lead to a situation where the temperature slowly creeps up and up on a long highway run.

I've been through a couple of those fail-safe thermostats already, and gave up on them altogether. Nice concept, bad execution. Every one I took out was stuck open.
 

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I have a "298" - it is a 289 that is bored .065 over. But I also have a new three row raditor and a five blade Ford fan. It has a 160 thermo in it (I plan to go to the 180 very soon). I have to be stuck in "parking lot" freeway traffic on a 95 degree plus day to even get the temp gauge to flicker much at all. I've check the actual gauge readings against a thermometer and have determined that the engine hardly ever gets over 175 degrees. I also use a coolant recover tank that feeds the coolant back in as the engine cools. This eliminates almost all air bubbles/space at the top of the radiator and improves cooling performance a bit as well.

Get a 3 or 4 row radiator, either a 5 or 6 blade Ford fan (there was one on (e)bay last week that had a starting bid of ten dollars that never sold! It would be perfect for you), and a recovery tank. Alternatively you could go with an electric fan so it on kicked in when you needed extra air flow.

John Harvey
 

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Since everything else has already been covered, I'll go for the long shot. By any chance was the engine and/or timing cover a late model like a reverse drive serpentine system? Just to make sure that the water pump is spinning the right direction...
 
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