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I have a 427 tall deck w/ 160 thermostats.There is a 4 core radiator and dual elec. fans I can not run a flex fan. Not room for one. The motor runs 200 most of the time just driving down the road at highway speed and 210-220 if you are speeding up and slowing down. Let me know what you think.


I posted the update at the bottom.

You say you have a 4core, how long has it been in use? May want to get it rodded out and hot tanked. You can also get a higher voulume water pump from Summit. Robertshaw makes a hig volume thermostat also.
What type of electric fas are they, or a better question may be what CFM are they rated at? Summit also sells a FlexAlite brand M150 BlackMagic fan that is rated at 2800cfm. I would say your motor needs atleast 2800cfm to keep it cool.
Good luck

have you tried running the 180 deg thermo. your 160 may not be staying closed long enough time for your water to cool down in the rad.

also, reduce the amount of anti freeze in your mixture. 100% water actually keeps the engine cooler than 50/50 ratio. water disipates heat better than antifreeze.

my 2 cents

ARQ.

my thoughts exactly!! if it flys right through, it wont get to cool down! it seems kinda bakkass'erds, but it be true /forums/images/icons/wink.gif

Burt's thoughts are the first ones I had. A 30/70 mix of antifreeze and water will cool the engine more efficiently than a 50/50 mix. Make sure that the cooling system is completely burped of air or it will tend to create local hot spots. Short of that, get rid of the copper/brass radiator and go with an aluminum radiator.

I had a 180 in there samething was happen.

that is the normal temp for a big block to run i had a 454 that would stay up close to 230 all day long while towing it would run at 210 when not loaded big blocks burn more fuel therfore they put out more heat

Automatic or manual tranny? If it's an auto is there a cooler in the radiator? Try an external tranny cooler. Make sure you get a good one though. Retarded timing or small fuel jets can make it run hot too. Make sure the radiator cap is good.

I have a 402 big block in my car, and it runs about the same temp as well, about 190-210 degrees normally. It's just normal for them to run warmer. You might try adding a external oil cooler if you don't have one already, a lot of heat can be disapated through the oil using these. A buddy of mine with a 454 got one of those aluminum water pumps that flows more evenly, and I think it dropped the temperature a little bit too.

My '95 dually came with a external trans cooler, oil cooler, a extra electric fan and a power steering cooler stock. And it runs around 210 when warmed up.

Thanks for all the help!! I am going to have the rad. cleaned And more fans after that. I will let you guys know how it goes. Thanks!

Ok, Well my 427 still runs 220-230 going down that highway with 180 thermostats. Since I first put up this post I have put in a new Radiator, I put in the 180 thermostats, new dual 13" perma-cool fans ( like Bob K) , and a new water pump. It has improved. I can let the motor idle or drive in town in stop and go trafic all day long with no prob. But try to go down the highway at a steady speed and It will slow go up the longer you drive. /forums/images/icons/confused.gif /forums/images/icons/confused.gif /forums/images/icons/confused.gif

I am in the process of replacing my twin electric fans on my BBC (4-Core radiator also!) with a QUALITY pair of Flex-A-Lite ones. The ones I had before were junk....though I didn't have anything to compare to at the time. A buddy of mine came over and was like...."Dude, when are these fans going to turn on?".....I told him that they WERE running!! /forums/images/icons/shocked.gif

They put out such a small amount of air, they couldn't keep the motor cool. These new ones move about 2500CFM, and when they turn on....you KNOW it!!! (LOUDER!)

The problem could be something simple too....like lousy fans. Though to be honest, at highway speeds my engine always ran about 180 degrees....it was only around town, or wheeling (less airflow) that the engine would get hot.

See my problem is the exact opposite I can cool my motor all day long no problem wheeling or driving around town. For example I drove my Blazer around town for 9 hours nonstop ( I did not even trun off the motor when I went in to a place) a few weeks back with no problems. As far as the fans go I can hear the fans over my motor and the dual 40 series flowmasters. It pulls enough air through the raditor that if you put a blade of grass in front of the grill it will hold it there. /forums/images/icons/grin.gif

they also have an additive you put in the radiator that is supposed to cool the engine by 20 degrees.im not sure what it is called,but it cost 25 dollars for the bottle of it.ive talked to a couple of people and they say it works.

Could ignition timing cause overheating? Could your gears be too tall for the tires you have?

Antoher thought is that your gage is not reading the temp properly?
Water Wetter is an additive that is suppose to reduce temps too?
Good luck

Are You Sure, that the Fan Shroud is Sealed up around the Radiator, not open at the Bottom, and the Fan Is 1/2 in the Shroud, and 1/2 out of the Shroud?

On My 454, I found a gap at the lower end of the Shroud, and sealed It up with High Density Foam Rubber.
At this point even in 95 Degree Temps, in traffic, It still runs Cool at Stop Lights, Moving, Whatever. Don H. /forums/images/icons/cool.gif

Do you turn your fans off on the freeway? At speed They might be slower than the incoming air and creating turbulance and poor airflow.

Well I think that I am closing in on the problem. The other day me and my friend put the tranny cooler back it to the rad. Now my motor run 210 all the time and 220-230 if you are going down the road at 50 MPH. /forums/images/icons/mad.gif Before I could drive 65-70 before it would run that hot. What do yall think?