240z with RB25DET engine - 3x workshops said it cannot be done

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personcalledj
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240z with RB25DET engine - 3x workshops said it cannot be done

Postby personcalledj » Mon Mar 30, 2020 7:38 am

I've taken my car to 3 shops, all who have said it's too hard to get done and they weren't prepared to look at it. I know for a fact it can be done, as there's a few examples online, however I have not been able to find any suitable reading material, until I found this forum!

It's a 1972 Datsun 240z - it did not come with factory AC.

It has an RB25DET engine from a 1995 R33 Skyline GTST - also without A/C.


I was hoping to use a standard OEM compressor and bracket to mount to the front of the engine, as I'm sure there must be common mounting points.

I'd need some new hoses and some AN fittings to connect them (right?)

Wire in a simple switch inside the cabin, ideally under the dash - if I feel clever enough, maybe a rotary dial for different strengths?

An evaporator would need to go in somewhere - would it be best to find an RB25 one too?


Right now I'll take ANY help I can, even if it just means I can be better informed the next time I take it to a shop!
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bohica2xo
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Re: 240z with RB25DET engine - 3x workshops said it cannot be done

Postby bohica2xo » Mon Mar 30, 2020 9:35 am

The 240Z was popular enough that there were aftermarket kits to add A/C built & sold. There were also factory A/C cars in 1973 I believe.

Contact the site sponsor AC Kits and ask if the aftermarket kits are still available. AC Kits was the originator of many aftermarket kits back in those years.

This is a pic of an OEM A/C setup from a Z
http://img.auctiva.com/imgdata/4/0/6/5/9/6/webimg/408414082_o.jpg

They are out there, probably expensive and likely nasty. All of that goes behind the dash, so no matter what you have in the engine bay it will fit the 240Z

You will need to find a Nissan with that engine and A/C to source OEM compressor brackets. Perhaps a non-turbo RB20 had A/C? Or you can fabricate brackets.

Nothing is impossible if you want it bad enough. A large, parallel flow condenser is a must have. Plenty of choices, this part is "universal".

Good luck with your project
personcalledj
Posts: 2
Joined: Mon Mar 30, 2020 7:32 am

Re: 240z with RB25DET engine - 3x workshops said it cannot be done

Postby personcalledj » Mon Mar 30, 2020 9:56 am

bohica2xo wrote:The 240Z was popular enough that there were aftermarket kits to add A/C built & sold. There were also factory A/C cars in 1973 I believe.

Contact the site sponsor AC Kits and ask if the aftermarket kits are still available. AC Kits was the originator of many aftermarket kits back in those years.

This is a pic of an OEM A/C setup from a Z
http://img.auctiva.com/imgdata/4/0/6/5/9/6/webimg/408414082_o.jpg

They are out there, probably expensive and likely nasty. All of that goes behind the dash, so no matter what you have in the engine bay it will fit the 240Z

You will need to find a Nissan with that engine and A/C to source OEM compressor brackets. Perhaps a non-turbo RB20 had A/C? Or you can fabricate brackets.

Nothing is impossible if you want it bad enough. A large, parallel flow condenser is a must have. Plenty of choices, this part is "universal".

Good luck with your project


Thanks for the quick reply!

I was aware of the old aftermarket kits, the only one that seems currently available new is the "Vintage Air" stuff - was hoping to save a bit of money if I can though!

So let's assume I can find an OEM compressor bracket and compressor (and that it all fits within the engine bay) - I'll get a couple of lines with custom AN fittings to the large parallel flow condenser mentioned (mounted inside the cabin?) - Electrical wiring is a little confusing for me, is there a common "go to" solution on these sort of home-brew kits?

Thanks again
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bohica2xo
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Re: 240z with RB25DET engine - 3x workshops said it cannot be done

Postby bohica2xo » Mon Mar 30, 2020 3:04 pm

No, the Condenser goes in the front of the car, preferably in front of any intercooler. It needs airflow to dump the heat collected from the car's interior.

The heat exchanger that goes inside the cabin is the Evaporator.

Refrigeration lines can be made up by any competent hose shop.

The basic components are:

Compressor > condenser . Receiver / dryer > expansion valve > Evaporator

With all of those components connected in series like that you have a refrigeration system. The discharge from the Evaporator returns to the compressor suction.

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