Hola,

I have an Alumitech radiator with dual Spal fans. In 90 degree weather, while driving on the highway (70 mph at 3,000 rpm)), it still takes both fans being on to keep the car near 200 degrees. I have a 180 stat in it. With the fans being on all the time, im worried about the life expectancy of the fans. Im running a stock ZZ4, and the radiator has foam sealing around it. Why is it running so hot on the freeway? Do I need a bigger radiator?

Thanks

Which side of the core are the fans on? Is anything else in front of the core? What water pump are you using?

pull fans on inside, a stock AC condensor and a B&M trans cooler on the outside. I may get a new condensor, since my AC works like crap, anyway.

A few thoughts. How accurate is your gauge? Most heat generation at speed can be caused by an overly lean conditions. Have you read your plugs to determine if your jetting is correct? Also, your fans that are mounted from the rear...is the mounting shroud(s) vented to the rear so the air thru the radiator will have enough surface area to be able to flow air at speed.

Chris at Spal told me the design life of their fans is 10,000 hours, except for the Extreme series 16 inch fans which is "only" rated at 2,500 hours.

A few thoughts. How accurate is your gauge? Most heat generation at speed can be caused by an overly lean conditions. Have you read your plugs to determine if your jetting is correct? Also, your fans that are mounted from the rear...is the mounting shroud(s) vented to the rear so the air thru the radiator will have enough surface area to be able to flow air at speed.
Steve brings up good points we all could take lessons from him .

there are several things that can cause your condition ...you have a good fan set up Spal twinn 11 with presure relife flaps to let the air pass trough ... i think the problem lies elsewhere ... flow at high speed ... what water pump are you running new or old ?
I never trust the gages...a i/r gun will give the true facts ...location of the sensor makes a difference.
lean conditions ... timming this all plays into things .
Iam asuming this is a 67/69 Camaro you have the biggest stock size rad you can get in there ...although I built a unit for a member here with a 26.25 wide core 30 inch wide over all at the bottom to fit between the fram rails.
this gave him aprox 2.75 inchs more width.
Steve do you have any other suggestions for overhauling ??

I'm the guy that Don special built the larger than normal radiator for and my cooling problems are GONE. I also used the dual Spal 11" fan set-up. I also installed an Edlebrock High flow water pump. I live in Tucson, Az. where the summer temps climb as high as 106 to 110 daily in the afternoons. My temp runs 180 most always, but when it does climb up to 200 the fans are set to go to high speed which brings the temp back to 180-185 almost immediately.
I cant say for sure what gave me the best result, the radiator/fan set-up or the high flow water pump, but I sure am happy with my entire cooling system now.
Good luck with your cooling problems, I know what a pain in the butt it can be.
Jerry

I'm with Don and Steve on this one.

Lean mixture or not enough coolant flow thru the system

pull fans on inside, a stock AC condensor and a B&M trans cooler on the outside. I may get a new condensor, since my AC works like crap, anyway.
sounds to me like the crappy a/c and overheating engine may be directly affected by lack of cfm thru the cores. before going too much further, even at the expense of having to recharge the a/c,(which you'd have to do anyway if you replaced the condensor), I'd be bound to attempt removing the condensor and drive the car to see if that makes any difference.