540 BBC in 69 - still not happy with temps

[rob07002]

Be cool direct fit
dual spal low profile 11" 950 cfm each fans
aluminum louvered shroud
weind aluminum water pump
tried 160, 180, and 195 Stewart emp tstat
50/50 antifreeze and water

180-195 at speed, Starts to creep up when stopped

not many options for electric fans that will fit. Anything left to try? I hate to do it, but may just go steel mech fan and stock shroud

[pittpens24]

Did you contact Be Cool? I had fitment issues with my 572 with what sounds like your same set-up on my C&R Racing Rad. C&R let me return the dual 11" and sold me a single 13" that pulls more air than the dual 11's. Worth a call.

[WallaceMFG]

Look into increasing the fan CFM somehow. Check all your shrouds and look for leaks or places it might be pulling hot air from the engine bay back to the radiator.

Also, what accessory drive setup are you using? I'd look into changing water pump pulleys if you can to get more pump flow at idle. Under drive pulleys reduce accessory speeds and can cause bad cooling/charging.

[btmatt]

Is you temp sensor in direct path of the coolant? A buddy had a 8-71 blown 468 where the temp sender in the head had been cobbled with several adapters moving the tip out of the coolant path. The heat off he header flanges would heat the sensor up and give crazy readings.

[rob07002]

Shroud is installed directly against radiator and I even have a block-off from header panel to support. 95%+ of the air is moving through the radiator. It immediately cools down once moving. I'm 90% sure it's my fans and just not enough CFM to cool at a standstill. I only have maybe 3" of room from the radiator to the water pump. Running OEM GM serperntine pulleys from an SS454 pickup application.

I found an 11" spal fan that puts out over 1400 CFM and MAY fit. So with 2 of these, I'm nearly doubling my CFM to 2900. If they fit, I'm hoping will solve. But certainly open to other thoughts and ideas. MarkVIII fan is out of the question, unfortunately, just not enough room.

[TMat]

I'm in the same situation wit a 69 camaro and big block, airflow at speed is fine as it cools done nicely.

At idle and slow speed, its difficult to keep it at a decent temp.
I was thinking of going to a 31 x 19 rad with larger fans, not sure what other direction to go???

[TheJDMan]

Looking at your fan shroud it looks like there is no room for air movement outside of the immediate area of the fans. No plenum effect if you will. I'm running a single 3400cfm Flex-a-Lite fan and have no overheating issues at all. Always buy the highest CFM you can find when shopping for a cooling fan. There is no such thing as too much air flow.

[rob07002]

Looking at your fan shroud it looks like there is no room for air movement outside of the immediate area of the fans. No plenum effect if you will. I'm running a single 3400cfm Flex-a-Lite fan and have no overheating issues at all. Always buy the highest CFM you can find when shopping for a cooling fan. There is no such thing as too much air flow.

The shroud is louvered, so air can pass during movement. I've since switched to stronger Spal dual 11" fans putting out 1240 cfm each and so far idling in the garage she's holding at below 170.

[btmatt]

have you tried to tape the louvers on the engine side? You may not create enough pressure drop for the fans to pull air across the exchanger due to the open louvers.

My C&R has rubber flaps that open at speed and seal when stopped and i have not had problems.