View Full Version : Cooling a centrifugal supercharged BBC

02-07-2005, 02:45 AM
Posted this in the cooling forum, but got no response, so I thought I would change forums.

I know there are a few of you out there with BBC engines with centrifugal superchargers.

My 540 has a vortech V7, and a air to air intercooler in front of the radiator. I am running twin thermo fans, a Team G pump, and a big alum radiator. At this stage I don't think airflow is the problem.

During days when the temperature gets to about 85 degrees, the gauge can show up to 205 degrees. The gauge is installed next to the thermostat. I would feel a lot more comfortable at say 180-190 degrees.

Can any of you guys give me some pointers as to what I can to make it run cooler? I have replaced thermostat (180 degrees), had the radiator cleaned (properly), the bottom hose does not collapse. I am thinking now it might be a timing issue, but I would be very interested to hear from other centrifugal owners who have had coolant temp problems.

02-07-2005, 03:07 AM
First and foremost with any cooling system in any car is getting the air through the radiator is most important. Question, is it running hotter sitting in traffic then cruising down the highway? If it cools down a lot when you hit the interstate, we need to work on the shroud and sealing the core support to radiator. There are tons of tricks.
If you have 2 fans and no shroud, you are only pulling air through those 2 fans, and are only cooling those 2 circles of the radiator. Are the fans mounted to some type of box shroud that covers the entire radiator core? If it is ambient temp sensitive, steps need to be taken to ensure it is drawing air from outside the engine compartment, and not mixed hot air from the under hood area.
If you ever take apart a late model factory built anything, you will see lots of rubber seals keeping the radiator tight to the core support, and also around the sides of the core support to keep hot engine compartment air from circulating in front of the radiator.
I would say more then half the cooling issues brought to us are cured with improving the shroud and sealing.

02-07-2005, 03:39 AM
Seems to take a while to get that hot and I think it actually gets hotter as I cruise on the highway, and picks up a couple of degrees if I give it a boot.

I have attached a link to some photos. By the way, its a 2 core rad.

I don't think it is a head gasket as there are no indications for this.


02-07-2005, 05:17 AM
Well, it looks like you have a nice shroud. have you tried moving the thermostat up? Also, when the Thermostat is open (which is all the time for you once it eclipes 180), are you moving the water to fast to cool it? The water has to be able to pass slow enough to actually cool.

02-08-2005, 01:10 PM
Yes-big tube diameter radiators allow coolant to flow too fast for adequate heat transfer. The other question is what kind of fans are yours exactly? I can suggest a better cooling system design if you are interested. gmachinz@juno.com

03-11-2005, 06:58 PM
Have you measured your oil temperature? The right oil cooler can make a big difference at the water temp guage. Heat pulled directly from the oil is heat the cooling system never sees.

03-14-2005, 12:06 PM
What is your mixture of Anifreeze to water?? Water is the best coolant but needs antifreeze for waterpump lubrication.. Use a 40% colant to water mix..

Have you tried WATTERWETTER?? I know alot of guys swear by it and i use it in my snowmobile and it cured my overheating problem

03-20-2005, 10:25 AM
Try 100% distilled water with Redline "Water Wetter" during the Summer and only enough antifreeze in the Winter to keep things safe.
I've used this method for hard-to-cool modified ZR-1 Corvettes.

03-24-2005, 06:56 AM
I've had a similiar problem as you mentioned earlier. I solved my looking at the rpm of the water pump pulley and upgrading to US Radiators desert cooler series of radiator. The desert cooler unit are triple flow units that have baffles to slow the coolant down and ensure the most heat transfer is occuring. Granted these radiators aren't the hi-tech aluminum that everyone expects to see. To me, The look is secondary to watching a temp. gauge climb to the stratosphere. Another tidbit - Use Spal fans. I'm running a 2600cfm pusher unit as a back-up to a Mopar heavy duty fan package. Good luck.

03-24-2005, 03:52 PM
BigBlue73, what kind of improvements did you get by moving to the new radiator?