Cooling Fan Parasitic Losses--Wow!

Oh yeah, I put my fly swatter back until I get a new alternator and Mercedes fan. It cools great, all the time but past 4k, I can definitely feel it. Though if you don't need every horses, it is kind of a bullet proof design.

I have seen that video before.  The results are a little different than this old article below.  In any case it can be summed up, direct drive fan = bad, flex fan = bad, mechanical clutch fan = better, thermal clutch = best mechanical fan, and of course electric is least power robbing overall.

MrSmog wrote: I am curious if less blades rob less hp? I would think so but not sure.

"Meet the new boss, same as the old boss."

MrSmog I'm thinkin more along the lines of factory stock fans. I plan to put a thermal clutch fan on this little 302 in my torino now and probably use it on the 351cj when I swap that in for 99% of drivin, but at the pure stock  drags I will have to run a factory fan. Just curious if there was any hp advantage of a 4 blade over a 5 blade. Looks like above in the print article it robbed 23hp vs 30 in the vid, but of course thats not really apples to oranges. Wonder if lower hp engines are labored more then a higher hp engine, or the hp loss is the same regardless? [/QUOTE wrote:   After seeing this I think I'd risk the $15 on one of the ebay electrics from China just to see what happens. I also have a feeling this has nothing or little to do with the engine and it's about the fan and car. Might be worth trying the submarine route also? For "quiet" they went to an inefficient but quiet screw and spun the RPM way up. They stayed quiet and are faster then ever. Kind of like what F1 did with the "super under square" engine.

Mr. Smog,

Do you know where Milan Dragway is? I'm about a half hour to 40 minutes minutes away unless it's a busy season for the farmers. Then it could be as much as 2 hours away.  When is the event? I'm usually gone for most of the fall but I could be up for it since you say it's for fun. No offense, but most drivers suck. If there is a god he invented professional, competitive drivers so the professional, competitive whiners could be herded to a common place. When you do get to participate, I'll be there.

MrSmog wrote: I'm thinkin more along the lines of factory stock fans. I plan to put a thermal clutch fan on this little 302 in my torino now and probably use it on the 351cj when I swap that in for 99% of drivin, but at the pure stock  drags I will have to run a factory fan. Just curious if there was any hp advantage of a 4 blade over a 5 blade. Looks like above in the print article it robbed 23hp vs 30 in the vid, but of course thats not really apples to oranges. Wonder if lower hp engines are labored more then a higher hp engine, or the hp loss is the same regardless?

I do not doubt the above findings about HP loses after switching from a mechanical 7 blade clutch fan assembly. I have been running a dual electric cooling fan assembly sourced from a '98 Ford Windstar for some time now, it cools my 472BBF very well even with running my A/C in traffic here in central Florida during summer temps. I see more stable cooling temps, better A/C performance, faster engine "spool-up"(biggest surprise), a slight increase in useable power as well as a bump in MPG's. I will never go back to a mechanical fan if there is an option for an electric cooling fan to do the job. The only drawbacks I have realized from my install was the initial costs for the parts and the wiring involved, but the advantages far outweigh these points.