ramcram

Here's a shot of my new Zirgo ZFU16S 3630CFM fan for the front of my 86ROW, running on the bench and drawing just 10 Amps as they claimed.
I have to say I was sceptical about the current draw but there it is. I did note that when I fired it up face down on the bench, the restricted air flow pushed it up to 15 Amps.
It's not quiet but not as noisy as I'd thought.

j.kenzie@sbcglobal.net

Best of luck with the fan. I had one a couple of years ago and suffered quality issues. Mostly the fan blade would come loose from the motor shaft. Happened twice and I went back to my 25 year old factory fan. Better than nothing, literally.
Good luck,
Dave

dr bob

Interesting test.

Keep in mind that the primary test of a fan is how much air it can move in actual service. And unless something amazing has happened in electric motor efficiency, motor current is directly related to horsepower and therefore to air capacity. So while low motor current is interesting, airflow capacity would be the first number I'd be looking for.

LT Texan

I blade design I would expect to effect efficiency too.

tv

The aftermarket fan I installed in place of the factory belt driver worked great. I installed it with fuse things on either side to protect the overall system and a manual switch. Kept my car cool and happy compared to the lousy times I had everytime I stopped in traffic previously.

dr bob

Blade design does help determine "efficiency", as in how much air moves at a specific DP, and more critically how much noise it generates. But generally, horsepower is still a great indicator of how much air is actually flowing, at least until the blades stall. Of course there are other factors that affect performance, like air temp, shroud design and how they fit the radiator. Then there's recirculation when the unit is installed. Most 'pusher' fans can't be fully shrouded, so there's a certain amount of recirculation that's inevitable. A deep shroud, fitiing tight against the radiator, is the best defense against recirc losses. 'Puller' fans work better with the same deep shroud if it's an option. A full-area shroud with bypass vents/flaps might be desirable too.

There have been several threads regarding the Contour/Mystique 'puller' fans and retrofiting to pre-S4 928's. The mid-years Taurus/Sable V6 fan setup is bigger and noisier, but offers even more airflow. I would probably look seriously at those options since they come with shrouds and bypass flaps.

danglerb

So far nothing I've seen touches the Lincoln Mark VIII fan, 18" blades fully shrouded with optimal size and 35 amps run at full power.

With a front fan I would guess a big gain would come from sealing the sides between the AC and radiator so it blows through both.

jpitman2

I tried one of those a few years ago, and it didnt do the job for me. 10A just isnt going to move 3600cfm IMHO. I have 2 x 11" SPAL fans, rated at 2700cfm the pair, and they each draw ~10A, and they do the job - 30 mins @ 100F, AC on, no problem. Just audible inside with the windows shut. SPAL list a high output 16" unit , but only rated for racing use, with NO WARRANTY, or service life listed.
jp 83 Euro S AT 54k

Imo000

The Mark 8 fan fits the 928?

ramcram

Shrouding on the front is a problem as you rightly say, especially with the big gap between the condenser and the radiator. As this pusher fan doesn't run all the time, only when the thermostat switches it on, shrouding could be a big restriction when the fan is off.
Here's a shot of the fan setup I used to replace the collapsed belt driven one on my 81 model, before the SC got in the way. Used a very smokey candle to combat recirculation. Not as easy to stop as one might think. It worked fine in our summers which can reach over 110F for days at a time.

ramcram

Woops, forgot the attachment.

ramcram

Thanks for the tip Dave. I'll remove the blade from the shaft before I fit the unit. I can check its fit and reassemble it with Loctite to prevent that kind a problem before it occurs.

danglerb

The Mark VIII blade shroud fits with about 1/2 inch to spare all around inside the factory mechanical fan shroud. I have one in my US 83.

Imo000

Nice!

ramcram

John, they do 3 different 16" fans and this the zf-U-16s, not to be confused with the MUCH cheaper zf-B-16.
We were'nt quite cool enough running around your part of the country at easter, with the old stock one on. Plus I must make a shroud for the 2 x 8" ones at the back of the radiator. Fixed to the core, I'm sure the fan hubs offer too much restriction.
Mike