FredR

JP,

Where did you get the notion from that the SPAL 12 inch dual fan kit is a "racing unit with lower projected life"- when I researched these items many years ago I never saw any mention of these being suitable for racing machines only albeit they would be just fine for such.. Have you seen the fan data for these items? SPAL offer an extra long life motor [whatever that means] for custom orders presumably for extra coin- you get what you pay for.

There is quirk with the motors that I brought to the attention of this community many [12+?] years ago. My units work well, run very quiet and the job lot cost the same as one replacement Bosch motor. If my kit falls over tomorrow I will simply purchase a new package or spare motors if available and think I got my money's worth out of them. The only problem I had last year was when one of the power connectors failed and that was easy enough to deal with. Every couple of years I pull the unit and run them up on the bench to heck for noise, vibration etc- to date no issues. The fans are also custom balanced.

The 12 inch dual fan package is a superb match to the stock radiator size unlike the unit you use which as you note is a tad smaller but if you are happy with how it works for you all well and good but personally I would not use that unit. The system is indeed much quieter than the stock fans that are somewhat agricultural by comparison- that is down to the very efficient fan blade design. I can have my unit out of the car in 60 seconds and whereas I have no doubt they are not as robust as the stock items they are very compact and the integrated module looks way better than the stock shroud does. Not for the Concours enthusiasts but as a practical alternative I suspect there is little that comes close to it other than the custom system Hans came up with.

If folks want to trawl the scrap yards and find things that work for them all well and good- personally I like to know I have something I can rely on for a good few years and experience has proven that to be the case with this kit that I modified to fit into my chassis and it does not look like a dog's breakfast.

V2Rocket

As mentioned OEM parts are generally going to have much more durability testing than anything aftermarket, even a quality-reputation part like a SPAL.
They do let you make a clean custom shroud though, so appearance may go that way.

But I'd bet the airflow from the $25 boneyard Taurus/V850 fan would spin a SPAL backwards in a head-to-head test.

jpitman2

Fred,
When I researched my SPAL unit I also saw they listed a 16" 3000cfm unit. On the SPAL sites they noted it was a racing unit with reduced life as the motor was less well sealed, or words to that effect. I dont think I ever connected the 3000cfm unit with a dual 12" set. I also saw the same 16" fan on non-SPAL sites rated at 3000cfm, but without the racing disclaimer, hence my warning. I went for the twin 11" set as the dimensions of the twin 12" set looked harder to fit on my 16V - IIRC there are some differences down there. Doesnt the dual 12" frame hang outside the core at the ends?
FWIW re wiring these dual units, I power the LH fan from the original factory wiring (sensor and relay), and the fire the relay for the second fan off the first fan's power, with power for the second fan coming from the hot post via a fuse.
I still remember fondly driving a Blazer, and a couple of Rangies in Riyadh at 45C ambient, and never worrying about the car's temperature - just would the AC keep going flat out!
jp 83 Euro S AT 57k.

DeWolf

This is the fan I'm using. It's quite large and apparently pulls more air than the twin setup used on the earlier V8 cars. This fan is used on the Australian 2008 FG Falcon V8. Ford AU actually went from a twin setup to this large single. The shroud is the same dimensions as the 928 radiator.

FredR

JP,

With you now- it seemed as though you were referring the 12 inch dual fan setup. This item sits nicely over the radiator with the frame lapping the inner part of the end tanks and could not be a better size for the 928 radiator. When it comes to anomalies the twin fan unit is a little bizarre- both motors as rated as "long life"- [whatever that means] but the motors have different specs ingress protection wise- which to me is utter nonsense. Of course I do not see rain over here but if I one wonders whether the lesser of the two would hold up- absolutely no reason for this. Whether it is a weak link or not I do not know but I know it caused some consternation when I pointed this out. Even though I pointed this out to SPAL I note they still do the same some 12 years later.

FredR

Spencer,

This is not a farting contest-

As long as the unit fitted provides the necessary airflow anything additional is just wasted power. The SPAL unit seems perfectly matched to the 928's needs. I'm sure this unit will not match the durability of the Bosch motor units [mine packed up when the car was some 12 years old] but then the entire piece of kit cost the same as one Bosch motor unit. My current kit has lasted about `12 years to date and still runs very quiet but I expect something will pack up one of these days and if and when it does I will simply purchase another unit just as I do with things like water pumps from time to time. Aesthetically speaking I doubt there is anything out there to match it either.

For those that like to go sniffing around junk yards and get a good deal good luck to them but realistically one usually has no real world clue as to how long such items will hold out.

jpitman2

Scott - the big single fan's advantage will be probably a bigger swept area (one motor vs two), and one set of tip losses. Disadvantage is less core area covered. That shroud could do with some blow open flaps to improve the flow of ram air in the corners.
jp 83 Euro S AT 57k

Kongmiami

DeWolf

^ I will be.

SwedeInSiam

I removed it with my SPAL dual 11" fans. Have the fans start on half speed with A/C and kick in with full speed when the dual temp switch I have installed in hose goes into high.
Works fine for cooling in Thailand.

DeWolf

New electric fan fitted into the original shroud quite well. This thing moves some air on high speed that's for sure and it's quite to boot.

DeWolf

And in the car.

Kongmiami

DeWolf

^ The one in post 19. I cut away all the shroud which left the fan housing and the fan. Turned the factory 928 two piece shroud into a single unit by bolting it together and then removing a couple of tangs on the radiator. Fan and shroud now drop down from above in one piece.

dr bob

Some technical thoughts:

-- Both the alternator and the electric fan motors are less than 90% conversion efficient. You'll get somewhere south of 0.8 HP work out of the electric fan vs HP needed at the alternator. You get heat at both sides as change. Compare with the thermo clutch drive that has no such losses.

-- The factory system transfers only the HP needed to keep the engine cool. The fan spins at a fraction of engine speed that goes up and down with the temperature of the air that's passed through the radiator.

-- On factory cars with electric primary cooling fans ('87+ cars) the power for the fans is drawn from the battery end with dedicated feeders. Folks talk about adding a relay or controller fed at the jump post area. The front-of-engine primary conductor is undersized for the duty, and the original wire has deteriorated. If you proceed with power from the jump post, upgrade the primary feed from starter to alternator and on to the jump post. Think 4ga marine cable (fine-strand tinned copper) as a minimum replacement standard.

-- Plan on an alternator upgrade to support the additional current loads for the fans. The alternator ratings can be a little confusing, as they are rated at a lower temp and higher engine RPM than we tend to see in service. This particularly applicable to auto trans cars. Look hard at Greg's high-current replacement if you want to keep everything happy.

-- I haven't looked hard at what's needed to replace the factory fan and clutch with a perhaps more modern assembly from a later American car. Mark A mentioned somewhere that he has a solution. Worth looking into IMO before putting less than factory electric fans in.