550 engine cooling improved!

@maranello72 commented in post #72 that stock fans drew 20A, and according to this source, 10ga Copper wire will allow for a 30A current draw, suggesting that any type of 10ga Copper wire should be large enough for this application?

 

Thank you, I thought I had seen a post somewhere that listed the current draw but I couldn't find it. If the fans do draw 20 amps, then 10ga wire should be plenty heavy duty enough. Then that begs the question, why are folks 'upgrading' to 40 amp fuses? Especially when the 10ga wire is only rated to 30 amps? Makes me wonder what the 'startup' current is.

 

Its called the In-rush at startup. And that will pull momentarily upwards of 1.5x the sustained rated Amps. I searched everywhere for a true technical answer, but found it is widely shown across all sorts of vehicles that, especially with Spal fans of these size, a 10g line and 40a fuse yields consistent operation and a 30a fuse will seemingly be less reliable.

I did find this article on the relevance of wire length having just as much effect vs sustained draw on a particular gage.

http://www.offroaders.com/technical/12-volt-wiring-tech-gauge-to-amps/

The total length of my longest harnesses is right about 10 feet for the left fan. Well within a safe draw for sustained under 30a and in-rush over it

 

Correct me if I'm wrong, but if the In-rush at startup on a full stock set up doesn't even cause the stock 30A fuses in the fuseboard to melt, doesn't that confirm any further that the stock wiring cannot support even just the stock fans, at least to their full potential?

 

Well, my Euro 550 came fitted with 30A fuses for cooling fans, in line with what is mentioned on the sticker on the fuseboard panel, the owners manual and the workshop manual.

 

Agree! Should include a surf board actually.

 

I have a digital display on my car to monitor the engine compartment temperature. While the fans are running and engine is idling. Is is about 70 degees Celcius around the brake master cylinder. After you stop the engine, the temp rise to 90-100 degrees when it is about 30 degrees Celcius out side. In ***renheit that would be areound 210 degrees when it is 88 outside.
What I have found out is that the battery due to its location is also the same temp... No wonder they never lst more than a few years. Secondly, the voltage regulator in the alternator will lower the chard voltage quite a bit due to the heat because they are built to do that. This also slows the fans down and the battery gets less charge. To hve the vattery in the trunk would be much better. And louvers in the hood so the heat can com out! When the car is rolling at running speed or more, it is not really a problem, but at standstill the heat is trapped in the engine compartment. Stupid construction. I have checked if there could be installed fans to the side vents in the fenders, but it is not easy to fit down there. Most of the heat goes out theough the wheel arches. On a hot day, you can see the air is blury if you look over the wheel arches...

 

When in doubt.... (results may vary)
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I don't claim you are incorrect, I was just stating that mine came with 30A fuses as I checked this last year when first reading this thread and found no discrepancies between my fuseboard and the literature. I will check again for sure.

Many thanks to you for starting this thread in the first place, btw!

 

Good info, thanks. Having the headers ceramic-coated may be the next step. It has worked well on another one of my cars.

 

The in-rush can be as high as 3x nominal load for an electric motor, but only for a fraction of a second, not enough to blow a 40A fuse. 30A fuses on the other hand won't last many cycles. The stock wiring is OK as there are two cables wired in parallel for each fan out of the fuse board, each 2.5mm2. My harness in the foot well bypasses the fuse board and plugs into those wires. This improved the cooling a lot, even before fitting the newer, slightly more powerful fan.
The copper traces in the fuse board provide an insufficient cross section and lead to considerable voltage drops.

 

I built my 1969 Meyers Manx vintage Baja racer in my garage (with lots of help).

On that project I got a Manx custom wiring harness from a guy in Florida (at the time I was impressed and felt like price absolutely equaled value).

I’m excited today because I got a new “bespoke” fan wiring harness from @Aerosurfer and WOW it’s #gorgeous. Perhaps here quality exceeds price paid!

I’m impressed, so nice, so clean.

VERY grateful - thanks — Eric
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Thanks Eric! I am realy happy with how these are coming out. It is a great supplemental upgrade to both cooling and electrical system on our cars.

I have been in production on these when I have been home and have available for both 456 and 550 cars ready to go, with more in about 2 weeks after vacation. It was asked last page about wiring. All wiring is now Automotive Cross link GXL/TXL or Marine Cable. Happy to answer any other questions.

 

Wow, I walked right into this exact repair the hard way (after chasing cooling “issues” for 2 years before stumbling upon this thread). This would have been the smartest thing to do first looking back.

GREAT value add to the community. You may as well recommend (or retail) the SPALs too but I know that gets dicey with all the 456/456M, 550 & 575 variables !

Gobble/MSW and now this….good stuff.

 

You guys keep this up and your cooling will be as good as a 575.

 

Stefano @maranello72 seemed to say that stock fans were up to the job already. The way I understand it is that the upgraded Spal fans do perform a little better than the stock ones but are not an absolute need contrary to the external harness, at least if the stock fans are in good working condition.

 

To many different setups for me to recommend a particular SPAL combination, especially since Im still running stock fans on my 456. Be it upgrade or replacement the end user should decide what setup best fits their radiator. My harness still works in all configurations.

But would need to verify that the Metro-pack 280 connector is still used on any newer SPAL fans. Merek, your fans you posted on page 2 use spade fan plugs instead of the locking Metro-pack plug that came originally. Its not wrong or incorrect, but I would need to know if I build it differently or make an adapter harness
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Hi Nick. Those connectors are exactly the same as on my 1987 Maserati Biturbo. And they have almost melted due ti corrotion and heat inside... Those are junk! I cut the connectors off and solder jointed the wiring. I bet the new fans will last for another 25 years no worries of not having a connector. If I have to take the radiator out, I just re-solderjoint the wires. In my opinion, a much safer solution...

 

Which are you talking about? The white plastic ones? I would agree, its a consumer part with a pretty universal application.

I'm using the same ones that Ferrari (and others use in the automotive world) Metripack 280. Not flimsy or lightweight and plug right into stock

 

Can you clarify the improvements the 575 has over 550 (and 456 cars). Had someone reach out to me about a harness for his 575. I told him not developed for 575 cars as its not generally needed, but i couldn't specify why...
Is the improved shroud and fans enough that 575 cars dont seem to have the same issues or are there other differences between them as well? Already assuming the end user has a properly maintained cooling system.

Is electrical theory the same as earlier cars?

 

Shroud, fans, different impeller and drive pulley. Silicone hoses in some spots. Seems like the electrical boards were better, too. I think many of the 575 cooling systems were better maintained, too, since they are newer and never bottomed out in price as much as the 550.

 

For anyone wanting to upgrade fans, these new SPAL 16" fans came across my feed. Says specifically about reduced in-rush loading.

No other affiliation. Nor have i done mine.

https://www.streetmusclemag.com/news/spal-introduces-new-16-sealed-brushless-high-performance-fan/

 

I put a single 16" SPAL on another hot rod of mine years ago. It was the older brush type technology - not one of these new brushless models, and I was able to use the OEM shroud, which was designed for a single 16" belt drive fan. It performed well, but I also upgraded the radiator, so it wasn't exactly an apples/apples comparison.

IMHO, the secret to success with changing/upgrading fans is to make sure you have a full coverage shroud that will enable the fan to pull air through the entire face of the radiator. That, I believe, was the downfall of the 550 fan/shroud arrangement which (IIRC) only covers between 2/3 & 3/4 of the radiator and Ferrari fixed that oversight with the 575M fan/shroud design.