New "euro" cooling fan performance

[artart]

Just replaced my broken OEM fan and shroud, with a new thin blade fan and new shroud and cap, flushed radiator, refilled with 50/50 and Redline. Bled water pump and intake. Ran once or twice without incident. Yesterday sitting for 20 minutes in the Bank teller line (a whole nother story!) I saw gauge reach unprecidented heights, about 3/4 over. On the drive home it cooled to just above normal. Previous to the broken fan, typical temps were just below mid point and in heavy traffic maybe a smidge just above midpoint.
Got home and cooled it down, pulled cap, bled the intake several times while running in the garage for 35 minutes, thermometer in the radiator never got above 170, looks like the gauge reads about 10'F high.
Since everything else is OK or better, my guess is that the Euro thinner blade fan just won't do it here in North Fla, ambient temps yesterday were low 90's. I had seen warnings for using this blade in hot weather but my supplier said they sell them here all the time and they are located a bit south of me! And other suppliers didn't have both the blade and shroud in stock so it appears my haste and frugality to save shipping charges for two separate purchases has hurt me.
Thought with a cleaned radiator, new full shroud, new boosted coolant, and replacing the OEM fan which had small chunks out of it for some time already I'd be OK, but the facts are otherwise.

[otteud]

The euro fan is made for the higher speeds of europe and thus in the real world it is not enough. Try an electric fan and put a temp switch in line and do away with the fan blade.

[dwc]

My experience with the Euro fan blade on my '87 Spider has been only somewhat different. I'm in S. Florida, and it has worked fine for the last 2 Summers. And, with my Spider being triple-black, it seems to absorb every calorie of heat you might imagine from this environment. Not sure how to explain the difference, though, from your problem. Perhaps it's the coolant mix. I'm using 20% Dex-Cool in distilled water, with no other additives. The radiator is about 4 years old, and is a genuine OEM radiator, not a recore. The shroud is in place, and the t-stat is the 185 degree type. The temp gauge reading has been verified with an IR thermometer, and the needle is always just barely to the right of midline, even on the hottest days, with the car moving. It does run somewhat hotter idling in traffic, but not quite at the 3/4 level. Finally, my Spider is a non-A/C car, so there's no condensor or electric fan in front of the radiator core.

Also bear in mind that having the temp gauge at the 3/4 level does not mean the demise of your engine. If the engine runs at 210-215 sitting at idle in heavy traffic, so what. Many newer cars have got 195 degree t-stats, and electric fans that don't switch on until 210. You've got a pressure cap in place, so ypur boiling point should be in the area of ~245F, which is still a healthy margin.

Regards,

Dean
lutz, FL
'74 & '87 Spider Veloce's

[JoeCab]

I agree, the "euro" fan - which is also stock on US 1600 motors, will cause the engine to run a tad hotter, and pull just a tad better.

I put a euro fan on my 2000 GTV and it is usually no problem, but on a hot track day I did notice the gauge was hotter than it had previously been with the stock 2 liter fan.

Joe