Aluminum radiators

Lots of good info. Thanks. So this is a 350 hp engine. Do you think the 205 is good then or should I would to get it down a bit?

I'd run a 180 in there. Especially if your using your rad with the internal trans cooler. If I remember correctly, every 5 minutes of your trans fluid being 215 or higher shortens the life of your trans by 30 or 50 percent. High temps kill auto trannies.
180 will give you good heat, keep the engine happy and your trans fluid happy.

Joe73 wrote:I'd run a 180 in there.  Especially if your using your rad with the internal trans cooler.  If I remember correctly, every 5 minutes of your trans fluid being 215 or higher shortens the life of your trans by 30 or 50 percent.  High temps kill auto trannies.  
180 will give you good heat, keep the engine happy and your trans fluid happy.  

And run a external cooler in conjunction with the OE cooler.  My separate trans cooler gets hot enough to burn you...and that's after it already went through the factory cooler.

dynchel wrote:

Joe73 wrote:I'd run a 180 in there.  Especially if your using your rad with the internal trans cooler.  If I remember correctly, every 5 minutes of your trans fluid being 215 or higher shortens the life of your trans by 30 or 50 percent.  High temps kill auto trannies.  
180 will give you good heat, keep the engine happy and your trans fluid happy.  

And run a external cooler in conjunction with the OE cooler.  My separate trans cooler gets hot enough to burn you...and that's after it already went through the factory cooler.

DEFINITELY!! Fluid should go through your rad and THEN through an external cooler. I like the B&M stacked plate design.

I have a b&m cooler bought from super shops...lol remember them?

I have an new aluminum one with 1 big @$$ core & 1" tube.  When I broke in the motor it ran @ 210 with the pulley fan & two supplemental fans going @ 2-2500 rpm for 30 minutes.  After that when I ran the new carb @ idle (1500 rpm) for about 20 minutes to time & set the carb the motor ran @ 190.  I have a 160 degree thermostat on it now.  I might do the dual fan set up if it ends up running hot.  I thought I bought a 2 core  

This info is old and dated, but I bought a 4 row copper core radiator and it does not over heat. The reason, besides price, that I got it was back then there were some companies who would glue their aluminum radiators together instead of soldering and they would come unglued. I don't know if that problem still exists or not. JB

I will try and check the thermostat this weekend. I am just using the cooler in the radiator for the tranny. Don't have the cash for anything extra right now. I have no back brakes and can't even afford then as of yet. I will get there. It just takes time.

I have an aluminum radiator ( Champion ) that I bought off ebay. Works fine. It ran 175 degrees during the cam break-in, with a 180 thermostat. Still have the trans cooler in the radiator hooked up, but plan to bolt on an add-on cooler that I have, and run it in series .......

Heat is the mortal enemy of transmissions for sure.....  

Found out that I was wrong it wasn't running at 205 it was 195.  I did see it hit around 200 or so in traffic the other day.

The 195 temp is normal these days, but partly for the emission controls to work, and gas mileage. A 180 temp would add a bit more power.......

driveit wrote:Found out that I was wrong it wasn't running at 205 it was 195.  I did see it hit around 200 or so in traffic the other day.

It has a 195 stat in it. I run that in all my rides as we end up in fall its cold up here. Plus I has over heating issues in my 56 chevy running a 160 stat. I radiator guy told me to run a 195 as it was flowing to fast and coolant did not get time to cool down before going back into block.( like running no stat) After I put the 195 in I have never had a over heating problem even with the A/C on in both cars. Drive-its engine and the 56 chevy I just sold.

Just my 2cents. Its your engine now you can do what you want. To me if its not broke don't fix it!!!!!!!!!!!

Thanks, Wally. It seems to be doing fine. I am just to happy with how it is doing I just wanted to make sure I was mistreating it.

Wanted to help clarify a misnomer in this thread regarding thermostats and not meaning to step on any toes.  

Not running a thermostat does not change the time the coolant stays anywhere.  It is a closed balanced system that is pressurized by an increase in temperature and the flow rate of the water pump and the friction losses within the system.

The flow rate is constant as it is a function of the velocity of the coolant and the area (square inches, square centimeters or whatever) of each passage and is controlled by the water pump.

put a gallon through a straw = high velocity
put a gallon through a radiator hose = Lower velocity
either way a gallon gets through in the same amount of time in a closed system, it can't "back up" into itself.

Powerful water pumps keep cars cooler because the heat can be exchanged to the radiator quicker and more times per minute.


If a thermostat is a 180, the car cannot be running at 160.  Temps are measured at various places.   When temps are taken at the radiator, you could get a reading of 170 with a 180 stat, but if you took the temp in the cylinder head near cylinders 6 and 8, you'll likely see 190.  Take it in the water passage in the intake manifold, you'll get something else.

Running a thermostat generally increases the likelihood of a more stable or what is called "laminar" flow and help reduce air pockets.  Too smooth of a flow will create a middle zone of the flow that will not exchange heat as well as the edge of the flow.  The water passages being rough is a good thing as it create more surface area for heat exchange in the heads and block.

I prefer to not run a thermostat in my chevy motors, because it is one more thing to fail, but that is only because each of my cars are race ready and when a thermostat sticks open or shut, you will lose that round and go home early.  My Buick needs to operate at 160+ as it is computer controlled.  it is at the lower limit where the computer can compensate to help with detonation during turbo "activities".

For a street car, what has been said in the posts about proper operating temperature and moisture being removed from the crankcase, etc. is all correct.  Street cars should run a T'stat.  

For the racers out there, without a T-stat, I can enter the burnout box at whatever temp I want (strong electric fans).  Typically 160 on cool days and 170 on hot days (consistency is key and hard to get to 160 sometimes on hot days).  By the time the tree drops, the motor is at 180 (or 190) and then 1/4 mile later, crosses the stripe at 190 (or 200), every time. Almost every BBC makes its best power at 180 to 190 degrees.

Excellent info!

Very well said. That makes perfect sense.