Maxi_z

Hello Everyone

On my 964 3.8 RS replica ( C2 base car and 993 engine and electronics ) the aircon and ventilation system was deleted before I bought it.

The car is built to be used on track but I don t know exactley what was deleted completely and what was kept on the car.

When I worked on the dashboard area I removed the CCU unit ( not sure if it s a 993 or 964 version ) and noticed that the faceplate itself could easely be separated from the heavier electronic part so as anyway nothing was working I kept it disconnected and only fitted the face part for the look.

But I read on the forums that some oil cooler and maybe other fans should be connected to the CCU to work or should be modified.

I would like more details on how to check if the different fans are fitted on the car and working and eventually details on how to make eventual modifications.

I could of course fit back and connect the complete CCU but I don t know if originally it was makingthe fans work or not.

Thanks for any picture or link

Ubipa

Have these things been removed: the HVAC suitcase, the heat blower from the engine, and the ac condenser fan? If so, you would be left with the oil cooler fan in the front right. Did they switch to a front oil cooler or dual oil cooler with no fan? You possibly might not have any electric fans that need controlled!

ToreB

All CCU functions are described here:
https://www.bergvillfx.com/categorie...system-details
Cheers,
Tore

Maxi_z

The Heat blower from the engine is removed as well as the A/C compressor and the car is using an aftermarket exhaust with racing manifolds so no heater related parts there.

I don't know if the HVAC suitcase was removed I will look

There still is the oil cooler with it s fan in the front right ( I still have to check if there is a second one fitted ) but I don t know if the fan of that oil cooler is actually working or if it was working when the CCU was still connected.

Any easy way to see if the fan is working?

ToreB thanks for the link

Ubipa

The CCU originally controls the 2 speeds of the fan. The PO/builder might’ve set it up differently (i.e. external controller, temp relay, etc…). Go for a drive and see if it kicks on!

You can manually jump the original relay and see if the fan and resistor are functional. Check this link: https://rennlist.com/forums/964-foru...test-plan.html

I’ve decided to separate the control from CCU. Sourced a brushless fan and a config PWM controller that works off the OEM temp sensor. Just waiting on some waterjet for the shroud. Might be an alternative for you.

Maxi_z

Thanks a lot for your reply

The HVAC suitcase is still on the car but as mentioned before the ventilation never worked even when I left the CCU connected...

I did not know that on the 964 the CCU was really a part of the system to make other stuff work I tought it was just there for the ventilation and A/C...

So now I will look at the oil cooler fan to see if it works ( BTW if the fan doesn t work is there a big difference in oil temperature? especially on traffic? )

but I m also wondering... If I would still have a working CCU and HVAC suitcase should I have any ventilation work even if the engine blower was removed?

The previous owner made a nice car and the engine is built by a reputable tuner that probably did excellent work but I could not get much info on some not working electrical things ( ABS not working but no warning light, central locking not working at all, and no ventilation ) and to make things more complicated

it s a mix of 993 engine and ECM and 964 parts

Ubipa

At a standstill with the engine running, you need a fan on the oem oil cooler (just as they designed it). My engine doesn't like oil temps above 10pm

I currently have the CCU only controlling the suitcase (no AC, no engine blower)

Foxman

For what it's worth, I deleted the CCU on my MY 1990 C2, and deleted the fan on the oil cooler as well. I also deleted the HVAC suitcase. Even in light traffic, the temps stay below 9 on the gauge.

A gridlock in a summer swelter would not do so well, but air cooled engines don't like to sit in traffic.