Ferrari 400/412 Radiator/Cooling Upgrades

The 400i and 412 are vastly different in this area: the most advanced 400i had 2 Lucas Cooling fans in front of the radiator and one ASTI (yellow) fan on the back. By contrast the 412 has 3 ASTI fans on the back. The 412 cooling works (very) well.

The Lucas do look good, but do not have any shroud. They were also used on V12 Jaguars and DeTomaso. The yellow fans are crappy (aluminium casting is brittle) and hard to source. They had been used on Lotus cars as well as Renault Traffic (light trucks).

On my 400i I have replaced the yellow fan by a Mishimoto heavy duty fan. This required major relocation of components. I can hardly see how the same could be performed with 3 fans (remember I only have one fan between radiator and engine, while the other two are between radiator and bumper), so your best bet is to source 3 fans of the same size. Unfortunately there are no heavy duty fans in this form factor, so do not expect to double the airflow.

My own modifications : https://www.ferrarichat.com/forum/threads/cooling-enhancement.629805/
(the Stewart Component booster pump is a massive ugrade, but had to remove the thermostat )

Maybe that refurbishing the fans would be a nice idea: the motor commutators can be trued on a lathe (alternatively you can clean them with a blue eraser), fresh grease, new brushes, and adjust the motor end-bell so as to tune timing for best efficiency.

How I tuned my Lucas (the same could roughy applied for the ASTI) : https://www.ferrarichat.com/forum/threads/lucas-cooling-fan.586356/

As said, 412 cooling is more than adequate.

 

In the above mentioned posts you've got a link to the Lotus Guys and how they handle these fans : http://wikilec.com/view/Cooling_Fans

 

100% agree - I’ve never had cooling issues with my 412, even in 100+F temps here in California.

Ruben

 

On the 400, the front right fan will always work when the airconditioning is activated. Should be similar in the 412?

No easy way to swap the th400, due to the rigid torque tube setup and narrow tunnel. 4l60 case will not survive and is too wide (unless you accept to cut the leather next to the passenger seat). 4l80 is too long, but has some nice parts that can be used.

I've upgraded my th400: 4l80 sprag, fully rollerized, custom variable torque converter. ~$5000. Works really well, feels more like a modern tranny and shifts fast. If you are ready to bit the bullet for an additional $2500, you could add to the list ultra-light drums (John Kilgore or Jakes Performance).

 

360
The temperature switch at the bottom of the radiator should active the two fans not serving the A/C. That switch can be replaced if it has failed in "closed" position.


Are you having cooling issues? If so, check the voltage to each fan at the fan. If less than 11 V, consider adding relays adjacent to the fan with heavier wire for the power flow.
Ken

 

On the 400i, the AC only activates the one fan in front of the compressor. I think the Temp Switch in the radiator activates all 3 fans, but it might only be the other two. It is very easy to test; just "jump" the switch wires.
Ken

 

The early 365/400/400i did have a wiring diagram included in the owner manual. Unfortunately the later 400i and 412 do have a separate diagram, and I do not know of any "free to download" document... I would assume that when your AC is off and the engine is cold, all fans should be off. If this is not the case I would presume that radiator temperature sensor is grounded somehow.